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Dyspraxia, Motor Function and Visual-Motor Integration in Autism
... With the aid of the eye-tracking technology, both atypical visual fixation and oculomotor behavior has been frequently reported in individuals with ASD (Miller et al., 2014;Sumner et al., 2020;Wan et al., 2019). So far, several studies have shown that eye-tracking technology might be a promising tool to facilitate the objective detection of ASD by implementing the ML approach (Eraslan et al., 2020;Liu et al., 2016;Wan et al., 2019;Yaneva et al., 2018). ...
... For example, in the case of starring at a target while smoothly shaking one's head, visual attention is not altered but eyes move in the sockets. Despite that a few studies demonstrated similar oculomotor functions between individuals with ASD and their TD counterparts (Avni et al., 2021;van der Geest et al., 2001), atypical oculomotor performance has also been reported in people with ASD by a variety of studies (Miller et al., 2014;Schmitt et al., 2014;Sumner et al., 2020). For example, prior studies implemented visually-guided tasks, in which participants were requested to fixate on a peripheral target as fast as possible after focusing on a central fixation target. ...
... For example, prior studies implemented visually-guided tasks, in which participants were requested to fixate on a peripheral target as fast as possible after focusing on a central fixation target. It has been reported that compared to the TD group, participants with ASD exhibited reduced saccade accuracy (Miller et al., 2014;Schmitt et al., 2014), longer saccade latency (Miller et al., 2014), and increased instability of fixation (Johnson et al., 2016;Sumner et al., 2020) in these visually-guided tasks. ...
This study segmented the time series of gaze behavior from nineteen children with autism spectrum disorder (ASD) and 20 children with typical development in a face-to-face conversation. A machine learning approach showed that behavior segments produced by these two groups of participants could be classified with the highest accuracy of 74.15%. These results were further used to classify children using a threshold classifier. A maximum classification accuracy of 87.18% was achieved, under the condition that a participant was considered as ‘ASD’ if over 46% of the child’s 7-s behavior segments were classified as ASD-like behaviors. The idea of combining the behavior segmentation technique and the threshold classifier could maximally preserve participants’ data, and promote the automatic screening of ASD.
... Dyspraxia is a condition that can hinder motor development in children, impairing their ability to perform various physical activities (Anderson-Mooney et al., 2016;Scott et al., 2021). Therefore, an effective intervention approach is urgently needed to help children with dyspraxia overcome obstacles in daily activities (Miller et al., 2014;Waber et al., 2021). ...
... Dyspraxia is a condition that can hinder motor development in children, impairing their ability to perform various physical activities. Therefore, an effective intervention approach is urgently needed to help children with dyspraxia overcome obstacles in daily activities (Miller et al., 2014;Waber et al., 2021). ...
Dyspraxia in children is not a hindrance in training motor skills. The purpose of this study was to analyze the effect of gaming circuit-based interventions on their motor skills. This research method used one group experimental design with pretest-posttest design. The population of the study subjects were students with dyspraxia, with a sample consisting of seven purposively selected students. The instrument used was a series of four-pole games designed to measure students’ motor skills. The research procedure began by pretesting the students’ motor skills before the intervention. Then, a game circuit-based intervention was performed on all students over a period of time. After the intervention was completed, a posttest was performed to re-measure the students’ motor skills. Data from pretest and posttest were analyzed using SPSS statistical software version 23 to compare scores before and after the intervention. These findings provide positive support to the use of a game-based approach in improving the gross motor skills of children with dyspraxia in the context of physical education. The positive implication of this study is that the circuit game approach can enrich educational interventions for children with dyspraxia and provide better insight into the development of motor skills in this population through innovative approaches. It is recommended that further research focus on specific elements of circuit play that are most effective in improving gross motor skills in children with dyspraxia, with the potential to form better guidelines in physical education.
... Meanwhile, the group score of the HFASD was higher in motoric visual and social reasoning was contrary with previous research. According to Miller et al. (2014), children with ASD generally have weaker motoric abilities compared to TD children. However, this was not found in the current research. ...
... Meanwhile, the group score of the HFASD was higher in motoric visual and social reasoning was contrary with previous research. According to Miller et al. (2014) children with ASD generally have weaker motoric abilities compared to TD children. However, this was not found in the current research. ...
Intelligence plays a significant role in determining the severity of Autism Spectrum Disorder (ASD), thus understanding intelligence among children with ASD is important to guide planning of appropriate interventions. Scores on IQ tests as well as intelligence sub-components between ASD and typically developed (TD) children, reflect distinct underlying cognitive processes. Therefore, a comprehensive investigation of the neuropsychological aspects of children ASD may better refine our understanding of the cognitive abilities among children with ASD. The current cross-sectional study investigated differences in intelligence profiles and executive function among children with TD children and children with High-Functioning Autism Spectrum Disorder (HFASD). A total of 34 participants met criteria for inclusion with 24 participants in the TD group, and 10 in the HFASD. Some of the measures which were used included the SB-LM, Executive Function Indonesia (EFI), and Autism Spectrum Quotient: Children's Version (AQ-Child). Data were analysed using Spearman correlation and Mann-Whitney test. Results showed no differences in the intelligence profile in both groups, yet significant differences were found in the composite EF, Inhibitory Control, and Cognitive Flexibility. Additionally, there was a difference in the correlation of intelligence and EF variables between the two groups. Thus, it can be concluded that both groups show qualitatively different cognitive processes. A recommendation derived from these results is that comprehensive EF assessment and treatment should be conducted as part of the global evaluation of ASD patients, primarily to design an intervention to enhance their academic domain.
... Children with ASD are at an increased risk for VMI deficits (Green et al., 2016;Miller et al., 2014;Wadsworth et al., 2017). Green et al. (2016) and Miller et al. (2014) both captured the diminished VMI performances in children with ASD while Wadsworth et al. (2017) described the neurophysiology that causes these discrepancies between typically developing children and children with ASD. ...
... Children with ASD are at an increased risk for VMI deficits (Green et al., 2016;Miller et al., 2014;Wadsworth et al., 2017). Green et al. (2016) and Miller et al. (2014) both captured the diminished VMI performances in children with ASD while Wadsworth et al. (2017) described the neurophysiology that causes these discrepancies between typically developing children and children with ASD. This understanding of VMI was furthered to include gross motor implications (Bonifacci, 2004;Dowd et al., 2011;Englund et al., 2014). ...
Visual motor integration (VMI) is the ability to control hand movements through vision. Children with autism are at risk for VMI deficits although this correlation is well described in previous research not much else is known about the relationship between autism and VMI. This study investigated the potential predictors of VMI performance in children with autism. The impact of occupational therapy attendance, age, gender, and pre-Beery-Buktenica Developmental Test of VMI scores on post-Beery-Buktenica Developmental Test of VMI scores were analyzed. Secondary data from 104 subjects were analyzed using multiple linear regression. It was concluded that the pre-Beery-Buktenica Developmental Test of VMI score was the greatest predictor of the post-Beery-Buktenica Developmental Test of VMI score. Age and gender were not predictive. Occupational therapy attendance was not a significant predictor; however, there was a significant difference between pre and post-assessment scores. The findings of this study illustrate that children with autism who have VMI deficits can benefit from rehabilitation services, that all ages and both genders can expect similar positive outcomes, and that these positive changes were not limited by attendance. Professionals can utilize the predictive model to formulate realistic goals based on current VMI performance for both rehabilitative and school settings.
... Imaging studies have also identified atypical neural activations in areas of the brain related to motor control and visual processing [19][20][21][22][23][24]. It is possible that visuomotor integration mechanisms contribute to the broad range of motor differences observed in autism [25][26][27][28]. ...
... A previous study established a relationship between smoothness of kinematic profiles and visual perception differences in autistic participants' goal directed reaching [26]. Movement smoothness has previously been used as an index for motor performance in neurotypicality and neurodivergence [30][31][32][33]. ...
Background
Autistic children and adults have known differences in motor performance, including postural instability and atypical gross motor control. Few studies have specifically tested dynamic postural control. This is the first study to quantify movement smoothness and its relationship to task performance during lateral dynamic postural control tasks in autism.
Research question
We sought to test the hypothesis that autistic children would have less smooth movements to lateral static targets compared to neurotypical children, and that this difference would relate to specific movement strategies.
Methods
We used camera-based motion-capture to measure spatiotemporal characteristics of lateral movement of a marker placed on the C7 vertebrae, and of markers comprising trunk and pelvis segments during a dynamic postural movements to near and far targets administered in an immersive virtual environment. We tested a sample of 15 autistic children and 11 age-matched neurotypical children. We quantified movement smoothness using log dimensionless jerk.
Results
Autistic children exhibited more medial-lateral pelvic position range of motion compared to neurotypical children, and used a stepping strategy more often compared to neurotypical children. Autistic children also had higher log dimensionless jerk than neurotypical children for motion of the C7 marker. All participants had higher log dimensionless jerk for far targets than for near targets. Autistic children had longer trial durations than neurotypical children, and younger children had longer trial durations than older children across diagnostic groups.
Significance
The stepping strategy observed more often in the autistic group likely contributed to log dimensionless jerk and reduced movement smoothness. This strategy is indicative of either an attempt to prevent an impending loss of balance, or an attempt to compensate for and recover from a loss of balance once it is detected.
... Frequently, in the discussion leisure is comparing with concepts like free time, recreation and play (Miller andRobinson, 1963 toward Unger, Kernan, 1983), time and psychological state (Russel, 2004toward Boyd Hegarty, 2009). Some author's states that leisure is the same as play but the term of leisure is used for adult age, while play is used for child´s age (Berlyne, 1969toward Unger, Kernan, 1983; Roggman, Moe, Hart & Forthun, 1994). ...
... As children with developmental disabilities differ from each other in the type and degree of impairment, so they also differ in perceptual-motor abilities, they differ from each other, but also in comparison with children of typical development. The results of the study (Miller, Chukoskie, Zinni, Townsend & Traune, 2014) show that children with autism compared to children of typical development show a significantly higher level of dyspraxia, have a poor effect on tasks assessing basic motor function, and poorer performance on the test of visual-motor integration and a supplementary motor coordination test. The authors point out that although the sample size was small to examine the association between the measures, strong correlations were observed in the group of children with autism in the measures of visual-motor integration and motor coordination with practice. ...
Poštovani čitaoci, autori, saradnici, Zadovoljstvo nam je predstaviti novo izdanje časopisa Defektologija sa izmjenjenim nazivom-Istraživanja u edukaciji i rehabilitaciji. Razvoj defektološke nauke, teorije i prakse, ali suštinska promjena društvenog viđenja invalidnosti, rezultirali su, pored ostalog, izmjenom naziva defektologija u naziv edukacijsko-rehabilitacijska znanost. Samim tim, javila se potreba da se časopis Defektologija, koji je u kontinuitetu izlazio pune 23 godine, terminološki uskladi sa nazivom znanosti čije teorijske i praktične rezultate istražuje, prikazuje i unapređuje. Nadamo se da ćete u časopisu naći korisne i interesantne teme iz područja edukacijsko rehabilitacijske znanosti, ali i iz srodnih disciplina, a naša misija je da stvorimo prostor za dinamičan i progresivan istraživački dijalog. Zahvaljujemo se svima koji su nas pratili u dosadašnjem znanstvenom putovanju, ali i svima onima koji će nam se pridružiti u budućnosti. Uredništvo F O R E W O R D Dear readers, authors, associates, It is our pleasure to introduce you a new edition of the jornal Defectology with the changed name-Research in Education and Rehabilitation. The development of defectology as science, theory and practice, but also, a fundamental change in the social vision of disability, resulted in, among other things, the change of the name defectology into the name education and rehabilitation science. Consequently, the need for the jornal "Defectology", which has been continuing for 23 years to come, has been terminologically aligned with the name of science, whose theoretical and practical results are investigates, displays and promots. We hope that you will find useful and interesting reading from the wide field of education and rehabilitation science, but also from related disciplines, and our mission is to create a place for dynamic and progressive research dialogue. We thank all those who have followed us in the current scientific journey, but also to all those who will join us in the future. Editorial
... Frequently, in the discussion leisure is comparing with concepts like free time, recreation and play (Miller andRobinson, 1963 toward Unger, Kernan, 1983), time and psychological state (Russel, 2004toward Boyd Hegarty, 2009). Some author's states that leisure is the same as play but the term of leisure is used for adult age, while play is used for child´s age (Berlyne, 1969toward Unger, Kernan, 1983; Roggman, Moe, Hart & Forthun, 1994). ...
... As children with developmental disabilities differ from each other in the type and degree of impairment, so they also differ in perceptual-motor abilities, they differ from each other, but also in comparison with children of typical development. The results of the study (Miller, Chukoskie, Zinni, Townsend & Traune, 2014) show that children with autism compared to children of typical development show a significantly higher level of dyspraxia, have a poor effect on tasks assessing basic motor function, and poorer performance on the test of visual-motor integration and a supplementary motor coordination test. The authors point out that although the sample size was small to examine the association between the measures, strong correlations were observed in the group of children with autism in the measures of visual-motor integration and motor coordination with practice. ...
The role of employers in obtaining a job for people with disabilities can be crucial. The law on “Professional rehabilitation and employment of people with disabilities” was supposed to be a key factor in improving the position of this population in the labor market, but in practice this has not been confirmed. One of the major obstacles to the employment of persons with disabilities is the lack of a register of persons with disabilities where employers colud find potential candidates with appropriate skills and competencies. This research was conducted with the aim of identifying potential barriers to employment of persons with disabilities perceived from the perspective of employers. The sample consisted of 50 employers of both state and private companies in the city of Novi Sad. Employers were surveyed with a questionnaire created for the purposes of this research, modeled on the Employers' Motivation Questionnaire for Employment of Persons with Disabilities with the prior consent of the author. The results schow that the adaptation of the workplace and access to means of transport are the biggest obstacle when we are talking about employing people with disabilities. In order to gain a deeper insight into the perspective of employers regarding the employment of people with disabilities, it is important to take into account their direct experiences as well as what worries them and what they feel insufficiently competent when it comes to employing this population. Key words: people with disabilities, employers, barriers.
... Regarding saccadic eye movement, visually-guided tasks were typically implemented, in which participants were required to fixate on a peripheral target as rapidly as possible after focusing on a central target. Reduced saccade accuracy (Miller et al., 2014;Schmitt et al., 2014), longer saccade latency (Miller et al., 2014), and elevated instability of fixation (Johnson et al., 2016;Sumner, Hutton, & Hill, 2020) have been reported in individuals with ASD compared to their TD peers. Concerning visual pursuit, Sumner, Hutton and Hill (2020) found that children with ASD spent significantly less time when visually following a target, which oscillated in a horizontal motion at different frequencies (Sumner et al., 2020). ...
... Regarding saccadic eye movement, visually-guided tasks were typically implemented, in which participants were required to fixate on a peripheral target as rapidly as possible after focusing on a central target. Reduced saccade accuracy (Miller et al., 2014;Schmitt et al., 2014), longer saccade latency (Miller et al., 2014), and elevated instability of fixation (Johnson et al., 2016;Sumner, Hutton, & Hill, 2020) have been reported in individuals with ASD compared to their TD peers. Concerning visual pursuit, Sumner, Hutton and Hill (2020) found that children with ASD spent significantly less time when visually following a target, which oscillated in a horizontal motion at different frequencies (Sumner et al., 2020). ...
This study investigated the oculomotor performance in children with autism spectrum disorder (ASD) during a face-to-face conversation. A head mounted eye tracker recorded the eye movements in 20 children with ASD and 23 children with typical development (TD). Group comparisons were conducted on the randomness and the quantity of eye movement. The amount of time needed to reveal group difference was also examined. Results showed that the randomness of eye movement was significantly higher at all examined time durations, and the amount of eye movement was significantly greater within 3 s in the ASD group. These findings demonstrated an atypical pattern of oculomotor dynamics in children ASD, which might facilitate the objective identification of ASD during daily social interaction.
... In fact, a variety of other features could be obtained from the gaze behavior, including the number of fixations, entropy, and number of revisits [16,40]. Additionally, features extracted from oculomotor behavior are also recommended since atypical oculomotor performance has been extensively reported in individuals with ASD [41,42]. Future ML studies are encouraged to generate as many features as possible so as to allow for specification of the globally optimal set of features for ASD identification. ...
... With a relatively small sample, our results showed that combining features on visual fixation and session length could accurately classify children with ASD and those with TD. It is proposed that future eye-tracking ML studies could use features from gaze-based measures [8,9], visual scanning path [15], and oculomotor performance [41,42] to detect ASD. Finally, we recommend that a larger and younger participant sample should be tested with the ML approach by combining features obtained from different modalities (eye tracking, neuroimaging, EEG, and kinematic) to evaluate how these objectively measured features could contribute to the early screening of ASD. ...
Background: Previous studies have shown promising results in identifying individuals with autism spectrum disorder (ASD)
by applying machine learning (ML) to eye-tracking data collected while participants viewed varying images (ie, pictures, videos,
and web pages). Although gaze behavior is known to differ between face-to-face interaction and image-viewing tasks, no study
has investigated whether eye-tracking data from face-to-face conversations can also accurately identify individuals with ASD.
Objective: The objective of this study was to examine whether eye-tracking data from face-to-face conversations could classify
children with ASD and typical development (TD). We further investigated whether combining features on visual fixation and
length of conversation would achieve better classification performance.
Methods: Eye tracking was performed on children with ASD and TD while they were engaged in face-to-face conversations
(including 4 conversational sessions) with an interviewer. By implementing forward feature selection, four ML classifiers were
used to determine the maximum classification accuracy and the corresponding features: support vector machine (SVM), linear
discriminant analysis, decision tree, and random forest.
Results: A maximum classification accuracy of 92.31% was achieved with the SVM classifier by combining features on both
visual fixation and session length. The classification accuracy of combined features was higher than that obtained using visual
fixation features (maximum classification accuracy 84.62%) or session length (maximum classification accuracy 84.62%) alone.
Conclusions: Eye-tracking data from face-to-face conversations could accurately classify children with ASD and TD, suggesting
that ASD might be objectively screened in everyday social interactions. However, these results will need to be validated with a
larger sample of individuals with ASD (varying in severity and balanced sex ratio) using data collected from different modalities
(eg, eye tracking, kinematic, electroencephalogram, and neuroimaging). In addition, individuals with other clinical conditions
(eg, developmental delay and attention deficit hyperactivity disorder) should be included in similar ML studies for detecting
ASD.
... Motor impairments have been observed in 50%-85% of individuals with ASD, with the main symptoms of deficits in visuomotor coordination and balance, muscle tone, and gait abnormalities (4,5). Large cohort studies and systematic reviews suggested that these motor impairments potentially represent initial and primary features of atypical symptoms in autism (6). ...
Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders characterized by social interaction deficits, restricted interests and repetitive behaviors. The co-occurrence of motor impairments exacerbates the severity and societal impact of ASD, but the underlying mechanism remains to be elucidated. Research on the comorbidities of ASD including motor impairments could benefit in the life quality improvement in patients with ASD. Here we aimed at investigating the motor behaviors in mice with Trio deletion in Purkinje cells (PCs), and further exploring the cellular and molecular mechanisms. The protein level of Calbindin as PCs’ marker was determined. Behaviors including spontaneous locomotion activity, rotarod, beam balance and gait were tested in mice with the ages of 12-week and 20-week. Magnetic resonance imaging (MRI) scanning with T2 and DTI sequencing was performed in 12-week old mice. Although Trio fl/fl; Pcp2-Cre mice showed significant impairments of spontaneous locomotion activity in both 12-week and 20-week ages, only the 20-week but not 12-week Trio fl/fl; Pcp2-Cre mice showed extra mild abnormal motor, fine motor coordination, and gait. The decreased expression of Calbindin existed in both 12-week and 20-week old mice compared with control. Differentially expressed genes analysis from RNA-Seq and Gene Co-expression Network Analysis (GCNA) showed that Syne1 and its co-expressed genes were upregulated in Trio fl/fl; Pcp2-Cre mice compared to controls. In addition, abnormal ADC values suggested the long-term chronic damage in the cerebellum. Together, our findings indicate that the motor dysfunction in ASD are affected by Trio deletion in PCs with delayed in onset, accompanied with alterations in MRI, histological, and epigenetic level.
... Examples of this include decreased accuracy in the initial force output to attain a target Wang et al., 2015), higher error rates in a repetitive aiming task (Papadopoulos et al., 2012), and a lack of anticipatory changes in muscle activity prior to a predictable change in load (Schmitz et al., 2003). Difficulties using visual feedback to adjust movements are also identified (Ament et al., 2015;, and visuo-motor difficulties are also found to be linked to autism symptoms severity (Miller et al., 2014). Thus, our results added to those of these sensorimotor control studies seem to indicate that predictive mechanisms in motor control and cognition present significant alterations in autism. ...
There exist indications that sense of agency (SoA), the experience of being the cause of one’s own actions and actions’ outcomes, is altered in autism. However, no studies in autism have simultaneously investigated the integration mechanisms underpinning both implicit and explicit SoA, the two levels of agency proposed by the innovative Cue integration approach. Our study establishes a first complete characterization of SoA functioning in autism, by comparing age- and IQ-matched samples of autistic versus neurotypical adults. Intentional binding and judgments of agency were used to assess implicit and explicit SoA over pinching movements with visual outcomes. Sensorimotor and contextual cues were manipulated using feedback alteration and induced belief about the cause of actions’ outcome. Implicit SoA was altered in autism, as showed by an overall abolished intentional binding effect and greater inter-individual heterogeneity. At the explicit level, we observed an under-reliance on retrospective sensorimotor cues. The implicit-explicit dynamic was also altered in comparison to neurotypical individuals. Our results show that both implicit and explicit levels of SoA, as well as the dynamic between the two levels, present atypicalities in autism.
... As previous studies described autism-related dyspraxia to be driven by motor coordination dysfunction and impaired visual-motor integration 8 , a structured examination of neurological soft signs (NSS) appeared as a promising option in detecting autism-associated motor impairment. NSS are originally defined as discrete, non-localizable deficits in motor coordination, sequencing of complex motor tasks and sensory integration 9 . ...
Neurological soft signs (NSS), discrete deficits in motor coordination and sensory integration, have shown promise as markers in autism diagnosis. While motor impairments, partly associated with core behavioral features, are frequently found in children with autism, there is limited evidence in adults. In this study, NSS were assessed in adults undergoing initial diagnosis of high-functioning autism (HFA), a subgroup difficult to diagnose due to social adaptation and psychiatric comorbidity. Adults with HFA (n = 34) and 1:1 sex-, age-, and intelligence-matched neurotypical controls were administered a structured NSS examination including motor, sensory, and visuospatial tasks. We showed that adults with HFA have significantly increased motor coordination deficits compared with controls. Using hierarchical cluster analysis within the HFA group, we also identified a subgroup that was particularly highly affected by NSS. This subgroup differed from the less affected by intelligence level, but not severity of autism behavioral features nor global psychological distress. It remains questionable whether motor impairment represents a genuinely autistic trait or is more a consequence of factors such as intelligence. Nevertheless, we conclude that examining NSS in terms of motor coordination may help diagnose adults with HFA and identify HFA individuals who might benefit from motor skills interventions.
... The fact that the current study found either a decline or a mild rise in PIQ scores across the three clusters longitudinally, but no signs of considerable improvement-at least not of the size of the improvement that autistic children in Cluster 1 exhibited in their VIQ scores, implies that the developmental progress in autistic children's visuospatial abilities was rather limited. PIQ vulnerability may signal a cognitive deficit in autism that impacts children's ability to perform in non-language-mediated tasks that rely heavily on visual-motor coordination (Faber et al., 2022;Miller et al., 2014) and executive function skills (Andreou et al., 2022;Memari et al., 2013;Mostert-Kerckhoffs et al., 2015;Peristeri et al., 2021). Interestingly, a very small cluster in TD children (n = 6; Cluster 2) exhibited almost identical PIQ trajectories to Cluster 2 in the autistic children, further suggesting that constrained PIQ growth may not be specific to autism at least for the specific time window (5-to-9 years). ...
Intelligence profiles in autism have been characterized by great variability. The questions of how autistic children's intelligence changes over time, and what factors influence these changes deserve study as part of efforts to document child autism profiles, but also because the relationship between intellectual functioning and children's background characteristics is poorly understood, particularly in a longitudinal context. A total of 39 autistic children and 39 age‐matched neurotypical children (5–9 years old) completed two IQ assessments at preschool age and up to 4 years later. Repeated‐measures analyses assessed longitudinal changes in the children's verbal (VIQ), performance (PIQ), and full‐scale IQ (FSIQ) at group level. We further sought to identify clusters with distinct profiles in each group by adopting an unsupervised K‐means clustering approach, and detect possible between‐subgroup differences in terms of children's socioeconomic status and autism severity. The largest cluster in the autistic group was composed of children whose PIQ significantly dropped at follow‐up, while the second largest cluster improved in all quotients; the smallest cluster, wherein children had more highly educated mothers than the rest of the clusters, was characterized by large improvement in VIQ. For the neurotypical children, there was a two‐cluster division; the majority of them improved in the three quotients, while very few dropped in PIQ at follow‐up. The relation between socioeconomic status and IQ changes was significant for both groups. The findings demonstrate both the complexity of intelligence changes in autism and the need to view this complexity through the lens of the children's socioeconomic diversity.
... Eye contact plays a crucial role in human social interaction. Individuals with conditions such as Dyspraxia and Autism Spectrum Disorders face difficulties in shifting their gaze, which leads to difficulty in synchronizing their central and peripheral vision [9]. Impaired eye movement can increase the risk of accidents, restlessness in movement, and increase stress. ...
... This could be due to differences in observer rather than questionnaire, as research notes situational specificity regarding observations of behaviour at school and home, where the nature of the different environments is likely to influence sensory responsivity (Palmer et al., 2022). For this reason, it was felt that such an important domain should be kept within the Tool as specific differences in the external senses are known to impact learning, for example inattentive children may have deficits in the auditory modality (Schmidt et al., 2019) and children with motor deficits may also have visual difficulties (Miller et al., 2014). Finally, the tool's fine and gross motor skills domain correlated significantly with the Little DCDQ (Rihtman et al., 2011) with large effect. ...
The objective of the study was to develop a prototype for an accessible, high quality, cost and time‐effective ‘Development Profiling Tool’ for use in reception classes. This would build a unique picture of every individual child's developmental at the beginning of their educational journey, meaning that interventions for any comparable areas of difficulty could be started early in the child's schooling. In this study, a prototype of the tool was developed and tested for reliability, validity and usability. Through content analysis of a range of screeners and the merging of targeted expertise, a single 54 question observational questionnaire was constructed that incorporated the five developmental domains considered to impact on learning and emotional well‐being: auditory skills; internal senses (proprioception and vestibular input); external senses (auditory, visual and tactile responsivity); fine motor skills and gross motor skills. Thus, the Development Profiling Tool was created.
Key points
For a child to learn successfully a number of developmental building blocks need to be present.
These include effective sensory responsivity and motor coordination.
This study develops a Developmental Profiling Tool to map every child's development at the start of their schooling.
The study also tests the prototype for reliability, validity and usability.
... However, most studies indicated that individuals with ASD exhibit lower levels of HRV than those without ASD. [12][13][14][15][16] The presence of movement disorders-including abnormal gait, clumsiness, and irregular movement symptoms-is an additional characteristic that supports the diagnosis of ASD. 1 Postural 17,18 and gait abnormalities 19-21 appear as early as infancy 22 and persist throughout childhood 23,24 and into adulthood. 25 Previous studies have shown that dyskinesia can lead to atypical movements 26 and limited social interaction 27,28 and is related to sensory integration impairment, 25 leading to the development of the core symptoms of ASD, 28,29 which could reduce quality of life. ...
Aim: To examine the effects of parent-delivered traditional Thai massage (TTM) intervention on heart rate variability (HRV) and gait in children with autism. Methods: This was a two-armed, randomized controlled trial conducted at the Haikou Special Education School in Haikou Province, China, between October 2021 and March 2022. A total of 48 children with autism, aged between 7 and 12 years, were selected from the school and randomly divided into either the parent-delivered TTM group or the control group (no intervention) in a 1:1 ratio. In addition to their regular daily school routines, the TTM group received 16 TTM interventions (twice a week), with each session lasting ∼50 min. HRV and gait parameters were measured at baseline, completion of the 8-week intervention, and 2 months follow-up. Results: The results of this study showed that the TTM intervention had a notable positive effect on HRV, with a significant reduction in low-frequency value (p = 0.001), and increased high-frequency value (p = 0.001), compared with the controls, and the advantages persisted during the follow-up period. However, only the stride length in the TTM group was significantly longer than that in the control group at the post-test (p = 0.039) and follow-up test (p = 0.043), while none of the other parameters of gait comparison showed statistical significance. Conclusions: Parent-delivered Thai massage increased HRV levels and stride length in comparison to the control group, and some effects of the intervention were maintained over the follow-up period. Clinical Trials Registry Identifier ChiCTR2100051355; September 21, 2021.
... In addition to sensory reactivity, children with ASD have difficulties in visual praxis, somatodyspraxia, and vestibular skills [2]. Characteristics such as changes in muscle tone, fine and gross motor functions, balance, and motor planning are also described with all these factors affecting computer use [3]. ...
Purpose:
People with autism spectrum disorder could benefit from physical activity during the pandemic and COVID-19 restrictions, mainly to maintain adequate physical activity. We aimed to evaluate the feasibility, enjoyment, and potential effect of telerehabilitation using a serious game named 'MoveHero'.
Materials and methods:
Registered in Clinical Trials (NCT04402034). We adopted a remotely run Telerehabilitation research design with 44 participants recruited: 22 People with ASD people and 22 non-ASD individuals.
Results:
All participants safely participated, 100% adherence to sessions, ∼60% enjoying the task, and significantly improved performance, with better performance for the NA group at most practice moments.
Conclusions:
Our findings support both how to implement a gaming intervention and the need to investigate the efficacy of serious games to motivate moderate intensity physical activity in people with ASD.
... This could reflect the importance of visual processing during PC in this population. Indeed, standing impairment in EC justifies the deficiency in PC mechanisms, which altered the integration of visual, proprioceptive, and vestibular systems [62,63]. Also, in this context, a psychomotricity training program relies on different inputs (visual, somatosensory) and leads to more sensory integration and environmental information which can affect the brain activity in children with ASD [64]. ...
Postural stability and control are essential motor skills for successfully performing various activities of daily living. However, children with autism spectrum disorder (ASD) exhibit significant sensorimotor impairments. The aim of this study was to investigate the efficacy of psychomotricity training on postural control (PC) of children with ASD. We recruited thirty children (age = 8.01 ± 1.2; weight = 31.66 ± 8.1 kg; height = 129.7 ± 10.8 cm) diagnosed with ASD (intellectual quotient > 50) to participate in this study. They were divided into two groups: the experimental group (n = 16) and control group (n = 14). Children in the experimental group were trained with psychomotor activities two times a week for nine weeks. Statistic postural balance was assessed before and after intervention and on different vision conditions. The results showed that the psychomotor training significantly improved PC in standing position under different conditions when compared to the control group, in all parameters (CoPA; CoPLX; CoPLy) (p < 0.01). Our preliminary findings suggest the usefulness of the psychomotor training in children with ASD on static PC.
... But individuals with RTT usually present severe dyspraxia and abnormal muscle tone, which is pathologically rooted in their impaired brainstem functioning (Smeets et al., 2012). In fact, oculomotor impairments are usually seen in individuals with autism (Miller et al., 2014) and dyspraxia (Gaymard et al., 2017). Furthermore, in neurodegenerative and motor neuron disorders for instance, a broad spectrum of oculomotor alterations is also involved (Jung & Kim, 2019;MacAskill & Anderson, 2016;Poletti et al., 2021). ...
Rett syndrome (OMIM #312750) is a progressive neurodevelopmental disease with clinical manifestations including loss of spoken language and apraxia. We summarized per PRISMA guidelines findings on their non-verbal social skills. Twelve studies (n = 479 females, 1.6–52 years) were sorted into a (non-)interventional design including video-coding, eye-tracking, and questionnaire studies. Across methodology, poor non-verbal social functioning was found, with eye gaze function being the most examined modality. Findings showed similar responsiveness to social stimuli as typically developing subjects but with difficulties in sustained attention and in recognizing novel social stimuli. Particularly, the music treatment showed to improve their skills. Concluding, due to severe movement disorder and apraxia, the brief gaze intent might be misconstrued beyond the caregiver’s perception or familiar situations.
... Imaging studies have also identified atypical neural activations in areas of the brain related to eye movement and visual processing (Brenner, Turner, & Müller, 2007;Luna et al., 2002;Takarae et al., 2007), and motor control (Mostofsky, Burgess, & Gidley Larson, 2007;Travers et al., 2017;Mosconi et al., 2015). It is possible that visuomotor integration mechanisms contribute to the broad range of motor differences observed in autism (Dowd et al., 2012;Miller et al., 2014;Williams, Whiten, & Singh, 2004;Mosconi et al., 2015;Wang et al., 2015). ...
... Findings were not replicated within and across different handwriting analyses, however, are in line with other studies among TD populations (e.g., Brown & Link, 2016;Volman et al., 2006). This suggests that the reported psychomotor function deficits of children and youth with ASD (e.g., Miller et al., 2014;Rosenblum et al., 2019) are not a predictor of poor handwriting performance, but rather, that relatively welldeveloped psychomotor functions are a predictor of good handwriting product performance for children and youth with ASD and TD controls alike. ...
Integration of cognitive, sensory, and motoric processes is essential for the production of handwriting, however, challenging for children and youth with Autism Spectrum Disorder (ASD). The objective of this scoping review is to identify potential underlying mechanisms of handwriting of children and youth with ASD by reviewing cognitive, sensory, and motoric body functions as predictors of their handwriting. The International Classification of Functioning, Disability, and Health – Children and Youth version was used to structure the analysis. Eleven studies (0.9%) met inclusion criteria. Results show that linguistic functions, psychomotor functions, motor control functions, and motor reflex functions predict handwriting of children and youth with ASD. This suggests these body functions are underlying mechanisms of handwriting of children and youth with ASD, encouraging future research to test these body functions as potential pathways to handwriting intervention for children and youth with ASD. Findings suggest a bottom-up approach to the development of handwriting interventions for children and youth with ASD.
... In line with findings of Rosenblum and colleagues (2019), visuomotor integration did not relate to any of the handwriting process characteristics. Thus, regardless of the generally lower performance of children and youth with ASD on visuomotor integration as compared to TD peers (Green et al., 2016;Miller et al., 2014;Rosenblum et al., 2019), its relationship with handwriting is similar for both groups. Altogether, this suggests that the ability to coordinate motor responses according to visual feedback, directly feeds into enhanced handwriting legibility. ...
This study tests a handwriting model for children and youth with Autism Spectrum Disorder (ASD) that displays the relationships between handwriting process and product characteristics, and the predictors of these characteristics. Structural Equation Modelling was used to test the model for children and youth with ASD (n = 50) and typically developing peers (n = 50), ages 10 to 15, for a copying and freestyle handwriting task. Findings suggest a generic handwriting model applying to both groups and both handwriting tasks. Unique effects for children and youth with ASD were identified for: (1) high interdependence of handwriting process characteristics, (2) longer pen stroke in air leading to better legibility, and (3) lower scores for executive functions leading to lower scores for legibility.
... These findings are consistent with prior studies (Bhat, 2020;Dowell et al., 2009;Fournier et al., 2010;Mostofsky et al., 2006;Nebel et al., 2016;Wilson et al., 2018;Wymbs et al., 2021) and add to the literature suggesting that motor impairments are characteristic of the ASD population and either may be considered a diagnostic criteria of ASD, similar to the recent addition of impairments in sensory processing (APA, 2013), or considered a common comorbidity. Further, motor related screening should be part of ASD evaluations (Bhat, 2021;Miller et al., 2014). ...
Previous research has shown that individuals with autism spectrum disorder (ASD) and developmental coordination disorder (DCD) may have overlapping social and motor skill impairments. This study compares ASD, DCD, and typically developing (TD) youth on a range of social, praxis and motor skills, and investigates the relationship between these skills in each group. Data were collected on participants aged 8–17 ( n = 33 ASD, n = 28 DCD, n = 35 TD). Overall, the clinical groups showed some similar patterns of social and motor impairments but diverged in praxis impairments, cognitive empathy, and Theory of Mind ability. When controlling for both social and motor performance impairments, the ASD group showed significantly lower accuracy on imitation of meaningful gestures and gesture to command, indicating a prominent deficit in these praxis skills in ASD.
Lay Summary
Individuals with autism spectrum disorder (ASD) and developmental coordination disorder (DCD) have social and motor skill impairments to varying degrees. This study compares ASD, DCD, and typically developing (TD) youth on a range of social, praxis, and motor skills. ASD and DCD shared similar patterns of gross and fine motor skills, but differed in skills related to making gestures. Specifically, our results also suggest that ASD has a prominent deficit in gesture performance and meaningful imitation compared to TD and DCD groups.
... Dyspraxia, a dysfunction of praxis, is identified as a DCD, and children with ASD are reported to have general praxis issues relating to not only physical imitations but also making gestures for instructions and operating objects [26]. The relationship between praxis and basic motor skills has been examined, and its effect on motor coordination has been shown [27]. Moreover, EF is a term that includes the process of controlling emotions, which is necessary to maintain an action to achieve a goal effectively through physical, cognitive, and emotional self-control [28]. ...
Motor coordination abilities are related to cognitive abilities and academic achievement in children with neurodevelopmental disorders. However, the similarities and differences of these relationships in children with autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (AD/HD) have not been explored. The purpose of this study was to investigate the relationship between motor coordination abilities, cognitive abilities, and academic achievement in Japanese children with ASD and AD/HD. Participants included 20 children with ASD, 20 children with AD/HD, and 20 typically developing children, matched for age and gender. Their motor coordination abilities were assessed with the Movement Assessment Battery for Children-2 (MABC-2). Furthermore, cognitive ability and academic achievement were assessed with the Kauffman Assessment Battery for Children-II (K-ABCII). Results demonstrated that the MABC-2 Total score significantly correlated with the K-ABCII Simultaneous processing, Planning, Total cognitive ability, Writing and Arithmetic scores in children with ASD. However, in children with AD/HD, there was no significant correlation between MABC-2 and K-ABCII subscale scores. The results of this study indicated that the relationship between motor coordination ability, cognitive ability, and academic achievement differs between ASD and AD/HD. This difference might indicate the non-similarity of neurological characteristics and encourage consideration for an approach that accommodates the features of neurodevelopmental disorders in children.
... 8,18,19 Miller et al also found that 60% of ASD cases have difficulty in gesture imitation tasks which suggests motor planning defect. 20 Berthier ML et al found that in cases of ASD with tourette's, NSS (in motor and somatosensory function) were present in six of seven subjects, while those with Tourette 14 This discussion summarizes that coordination problems, sensory dysfunction, and dysfunctional posture and muscle tone regulation were more strongly associated with ASD than with other psychiatric morbidity. ...
Autism spectrum disorder (ASD) is a phenotypically heterogeneous group of neurodevelopemental syndromes characterized by impairments in social communication and restricted & repetitive behavior. Neurological soft signs (NSS) are minor neurological abnormalities that aren’t a part of any fixed/transient neurological disorders. The most common NSS in ASD are motor incoordination, difficulty sequencing motor tasks & sensory disintegration.
22 participants of ASD satisfying the inclusion and exclusion criteria were assessed for NSS, using a semi structured performa & Heidelberg manual for neurological soft signs. The data was tabulated and analysed statistically.
The mean age of the participants was 11.63 years with 82% males & 18% females. 100% participants had dysdiadochokinesia (82% -adiadochokinesia), errors in the finger-nose test(71% unable to perform), right-left confusion (39% -making gross errors), difficulty in tandem walking(70% -significant balance problems), difficulty in fist-edge-palm (54% unable to complete task) & ozeretski test (78%- unable to perform). 94% had difficulty in pronation-supination (56%-failed to complete exercise).89% of the participants had difficulty in finger –thumb opposition (63%- unable do it).
NSS are present in a significant amount of patients of ASD & such patients should be assessed for the full spectrum of NSS.
... The term 'apraxia' in adult neurology literature is used to describe an acquired brain damage that results in impaired ability to perform the learned skill in the absence of underlying motor, sensorimotor, or cognitive deficits. In the pediatric neurology literature, however, the term "apraxia" is somewhat confusing and often describes a less serious form of developmental disorder as 'Dyspraxia' (Miller et al., 2014). A study conducted in 2008 with children with dyspraxia found that left-handedness was more common. ...
Aim: This study was conducted to determine the incidence of Gravitational Insecurity in individuals with Specific Learning Disorder. Material and Methods: We included 99 children, 65 boys and 34 girls, diagnosed with Specific Learning Disorder in our study. All children participating in the study were attending a special education and rehabilitation center. Physically independent individuals without any orthopedic or neurological diagnosis other than Specific Learning Disorder were included in the study. 99 children were evaluated with the Gravitational Insecurity Assessment and the data obtained were statistically analyzed. Results: Gravitational Insecurity is commonly seen in individuals diagnosed with Specific Learning Disorder. In individuals diagnosed with Specific Learning Disorder, the severity and incidence of Gravitational Insecurity increase with age, there is no significant difference between genders, and these individuals react to different movement patterns at different levels. In individuals diagnosed with Specific Learning Disorder with Gravitational Insecurity, postural symptoms of Gravity Insecurity are observed at higher rates than emotional symptoms. The incidence of both postural and emotional symptoms increases with age.
... The term 'apraxia' in adult neurology literature is used to describe an acquired brain damage that results in impaired ability to perform the learned skill in the absence of underlying motor, sensorimotor, or cognitive deficits. In the pediatric neurology literature, however, the term "apraxia" is somewhat confusing and often describes a less serious form of developmental disorder as 'Dyspraxia' (Miller et al., 2014). A study conducted in 2008 with children with dyspraxia found that left-handedness was more common. ...
Aim: This study was conducted to determine the incidence of Gravitational Insecurity in individuals with Specific Learning Disorder. Material and Methods: We included 99 children, 65 boys and 34 girls, diagnosed with Specific Learning Disorder in our study. All children participating in the study were attending a special education and rehabilitation center. Physically independent individuals without any orthopedic or neurological diagnosis other than Specific Learning Disorder were included in the study. 99 children were evaluated with the Gravitational Insecurity Assessment and the data obtained were statistically analyzed. Results: Gravitational Insecurity is commonly seen in individuals diagnosed with Specific Learning Disorder. In individuals diagnosed with Specific Learning Disorder, the severity and incidence of Gravitational Insecurity increase with age, there is no significant difference between genders, and these individuals react to different movement patterns at different levels. In individuals diagnosed with Specific Learning Disorder with Gravitational Insecurity, postural symptoms of Gravity Insecurity are observed at higher rates than emotional symptoms. The incidence of both postural and emotional symptoms increases with age.
... Ovo su teme koje su obrađene u literaturi. Problemi u oblasti vizuo-motorne integracije se često javljaju kod prevremeno rođene dece, dece sa poremećajima iz spektra autizma, dece sa razvojnim poremećajem koordinacije i dece sa raznim sindromima (Daun, Prader-Vili, Vilijamsov i drugi) (De Waal, Pienaar & Coetze, 2018;Heiz & Barisnikov, 2016;Lo, Collin & Hokken-Koelega, 2015;Miller, Chukoskie, Zinni, Townsend & Trauner, 2014;Pinheiro, Martinez & Fontaine, 2014). ...
Vizuo-motorna integracija (VMI) predstavlja nivo usklađenosti vizuelne percepcije i fine motorike te je bitno da obe komponente budu pravilno razvijene, ali i da su neometano koordinisane u zajedničku aktivnost. VMI je značajna u svakodnevnim životnim i akademskim aktivnostima. Cilj istraživanja je bio da se utvrdi nivo vizuo-motorne integracije kod dece predškolskog uzrasta, kao i da odgovori na pitanje postoji li veza između vizuo-motorne integracije i određenih socio-demografskih varijabli (pol i uzrast). Uzorak je činilo 74 dece predškolskog uzrasta, od pet godina i jednog meseca do sedam godina i sedam meseci (AS=6,66 godina; SD=0,44 godine). Istraživanje je sprovedeno primenom Razvojnog testa vizuo-motorne integracije (The Beery-Buktenica Developmental Test of Visual-Motor Integration - Beery VMI, Sixth Edition)(Beery & Beery, 2004) i Ček liste o usvojenosti vizuo-motorne integracije kod dece (Visual Processing Disorder – Checklist) nacionalnog udruženja specijalnih edukatora u Sjedinjenim Američkim Državama. Rezultati pokazuju da postoji statistički značajna povezanost između vizuo-motorne integracije, vizuelne percepcije i motorne koordinacije (p<0,05). Takođe, utvrđeno je da devojčice ostvaruju viši nivo postignuća na testu vizuo-motorne integracije od dečaka (p<0,05). Rezultati potvrđuju da je procena vaspitača usaglašena sa postignućima na razvojnom testu VMI. Iako deca na predškolskom uzrastu imaju prosečno razvijenu veštinu vizuo-motorne integracije, bilo bi preporučljivo sprovoditi skrininge iz ove oblasti da bi se na što ranijem uzrastu detektovala eventualna kašnjenja, obzirom na značaj razvijenosti VMI i njene povezanosti sa svakodnevnim aktivnostma i razvojem bazičnih akademskih veština.
... Imaging studies have also identified atypical neural activations in areas of the brain related to eye movement and visual processing (Brenner, Turner, & Müller, 2007;Luna et al., 2002;Takarae et al., 2007), and motor control (Mostofsky, Burgess, & Gidley Larson, 2007;Travers et al., 2017;Mosconi et al., 2015). It is possible that visuomotor integration mechanisms contribute to the broad range of motor differences observed in autism (Dowd et al., 2012;Miller et al., 2014;Williams, Whiten, & Singh, 2004;Mosconi et al., 2015;Wang et al., 2015). ...
... The research has noted praxis deficits in children with ASD, BPI, and CP [9]. Six recent studies including a meta-analysis found motor coordination to be negatively impacted by ASD [10][11][12][13][14][15]. Four recent studies found motor coordination to be negatively impacted by BPI ( [16][17][18][19][20]). ...
Original research articles regarding visual motor integration skills in children with developmental disabilities and the impact of occupational therapy were identified, appraised, and synthesized. Twenty-four articles were chosen for this review. Themes were noted during the critique of articles. Three themes emerged: "age," "gender," and "diagnosis." Regarding the impact on visual motor integration, there was strong evidence for age, moderate evidence for gender, and strong evidence for diagnosis. Future research investigating visual motor integration in children should control for age and diagnosis.
... As children with developmental disabilities differ from each other in the type and degree of impairment, so they also differ in perceptual-motor abilities, they differ from each other, but also in comparison with children of typical development. The results of the study (Miller, Chukoskie, Zinni, Townsend & Traune, 2014) show that children with autism compared to children of typical development show a significantly higher level of dyspraxia, have a poor effect on tasks assessing basic motor function, and poorer performance on the test of visual-motor integration and a supplementary motor coordination test. The authors point out that although the sample size was small to examine the association between the measures, strong correlations were observed in the group of children with autism in the measures of visual-motor integration and motor coordination with practice. ...
Perceptual-motor skills (PMS) are very important for the functioning of children in general,
including children with developmental disabilities, and enable a person to, based on the
stimulus through movement it acts on the space that is surrounded. This paper aims to review the research of enriched knowledge of PMS of children with disabilities, which emphasized the importance of performing activities of everyday life and the acquisition of academic skills. The papers collected a search of electronic databases using the keywords: PMS, children with disabilities, visual perception, gross and fine motor skills, visual-motor coordination, visual-motor integration. Criteria for the selection of papers have been published in full and in the last 10 years. A total of 12 works met the criteria. The results of the research review showed that children with disabilities have a limitation in PMS, and showed that PMS differ separately from the type and degree of difficulty, but differences also exist within the same category of children with disabilities. Implementation of education and rehabilitation programs improves PMS. The results showed that there is a correlation between PMS and activities of everyday life and a correlation between visual perceptions and the acquisition of reading skills. It is important to point out that PMS can be practiced and it is important to implement incentive programs for children with disabilities, but also children at risk for some difficulty, to prevent possible difficulties that children may have in performing daily life activities and in acquiring academic skills. The results of the presented research should be considered concerning the limitations of the presented research, but also to the limitations of this research.
... Additional transdiagnostic symptoms comprise, e.g. atypical motor [2], (social) reward [3], executive [4], mood, and emotion [5,6] processing. Combined, these difficulties incur a high cost to affected individuals and society [7][8][9]. ...
Background
Autism spectrum disorder (ASD) has a high cost to affected individuals and society, but treatments for core symptoms are lacking. To expand intervention options, it is crucial to gain a better understanding of potential treatment targets, and their engagement, in the brain. For instance, the striatum (caudate, putamen, and nucleus accumbens) plays a central role during development and its (atypical) functional connectivity (FC) may contribute to multiple ASD symptoms. We have previously shown, in the adult autistic and neurotypical brain, the non-intoxicating cannabinoid cannabidivarin (CBDV) alters the balance of striatal ‘excitatory–inhibitory’ metabolites, which help regulate FC, but the effects of CBDV on (atypical) striatal FC are unknown.
Methods
To examine this in a small pilot study, we acquired resting state functional magnetic resonance imaging data from 28 men (15 neurotypicals, 13 ASD) on two occasions in a repeated-measures, double-blind, placebo-controlled study. We then used a seed-based approach to (1) compare striatal FC between groups and (2) examine the effect of pharmacological probing (600 mg CBDV/matched placebo) on atypical striatal FC in ASD. Visits were separated by at least 13 days to allow for drug washout.
Results
Compared to the neurotypicals, ASD individuals had lower FC between the ventral striatum and frontal and pericentral regions (which have been associated with emotion, motor, and vision processing). Further, they had higher intra-striatal FC and higher putamenal FC with temporal regions involved in speech and language. In ASD, CBDV reduced hyperconnectivity to the neurotypical level.
Limitations
Our findings should be considered in light of several methodological aspects, in particular our participant group (restricted to male adults), which limits the generalizability of our findings to the wider and heterogeneous ASD population.
Conclusion
In conclusion, here we show atypical striatal FC with regions commonly associated with ASD symptoms. We further provide preliminary proof of concept that, in the adult autistic brain, acute CBDV administration can modulate atypical striatal circuitry towards neurotypical function. Future studies are required to determine whether modulation of striatal FC is associated with a change in ASD symptoms.
Trial registration
clinicaltrials.gov, Identifier: NCT03537950. Registered May 25th, 2018—Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT03537950?term=NCT03537950&draw=2&rank=1.
... The existing research is at a consensus that autism spectrum disorder (ASD), brachial plexus injury (BPI), and cerebral palsy (CP) affect visual motor integration (VMI) and that VMI may be positively impacted by occupational therapy intervention (Bumin & Kavak, 2008;Cho et al., 2015;Desai & Rege, 2005;Duff & DeMatteo, 2015;Green et al., 2016;Lu et al., 2016;Miller et al., 2014;Wadsworth et al., 2017). However, the research does not adequately address the potential relationship between occupational therapy intervention and the Beery VMI scores of children with ASD, BPI, and CP. ...
Data of 107 children (84 males and 23 females) who received occupational therapy services were collected. Data collected included age, gender, prescribed frequency of occupational therapy, number of sessions attended within the six-month timeframe, pre and post Beery Visual Motor Integration scores.
While the autism diagnosis emphasizes “deficits” in social communication, the article advances that sensory–movement differences underpin autism through a review of the following sources of evidence. This account critically challenges “autistic regression”, with evidence that sensory–movement features appear by birth as the earliest signs of autism and underlie the behavioral differences used for diagnosis, which may reflect adaptations to inherent differences and misunderstandings from others. Sensory and motor differences are salient to autistic people, but they often go underrecognized by others. They cause cascading effects in infancy on behavior and communication through differences in sensorimotor learning, automatic imitation, eye contact, sensory perception, and interests. The article then explains how sensory processing differences may influence reduced perceptual narrowing, which involves a bottom-up information processing style grounded in the surrounding environment. Furthermore, this bottom-up processing may grow from reduced sensory integration in feedback loops potentially involving the cerebellum of the brain. The article then moves into implications for the widespread consequences of these inherent differences on quality of life. The article closes with implications for autism as a construct (including underestimated empathy and pain), testing the theory, providing sensory-sensitive support and acceptance of autistic people, and applications to diverse autistic people. The theory may apply particularly well to autistic women and girls, autistic people with speech divergence, autistic people with ADHD, and autistic people with co-occurring sensory and motor-related neurodivergences. Throughout the article, the theory also provides clinical, neurological, and experiential evidence for sensory and motor differences as lifelong, challenging the notion of “losing” (an) autism (diagnosis) as instead reflecting (risky and not necessarily “successful”) camouflaging.
Introduction: Children with autism spectrum have disorders in cognitive tasks, including attention and memory. The aim of this study was to determine the effect of perceptual-motor exercises on the sustained attention and memory performance of autistic children.
Materials and Methods: The method of the study was semi-experimental with a pre-test-post-test design and a control group. The statistical population included the autistic children of Ahvaz city, 30 of whom were selected through available sampling and, after completing the autism scale, they were randomly divided into a homogeneous experimental and control group. Research tools included autism scale, continuous performance test and memory test. Both groups performed continuous performance and memory tests in the pre- and post-tests. The experimental group underwent perceptual-motor exercises for eight weeks, two sessions per week. Data were analyzed through independent t-tests and analysis of covariance with SPSS software version 26 at a significance level of 0.05.
Results: The effect of perceptual motor exercises on memory performance in subscales of general information, orientation, mental control, repetition of forward digits, logical memory, associative learning, and visual memory was significant (p<0.05). Also, perceptual-motor exercises were significantly effective in the variable of sustained attention in the subscales of ratio of correct response to target stimulus, ratio of correct response to non-target stimulus, correct response reaction time, omission error, and commission error (p<0.05).
Conclusion: Based on the results, perceptual-motor exercises can improve sustained attention and memory in children with autism spectrum. Therefore, it is suggested that the training and practice of perceptual-motor activities be included in the agenda of trainers and occupational therapists of educational and therapeutic centers.
Keywords: Perceptual motor performance, Memory, Attention, Autism spectrum disorder
It is estimated that 1 in 36 children are affected by autism spectrum disorder (ASD) in the United States, which is nearly a twofold increase from a decade ago. Recent genetic studies have identified de novo loss‐of‐function (dnLoF) mutations in the Down Syndrome Cell Adhesion Molecule (DSCAM) as a strong risk factor for ASD. Previous research has shown that DSCAM ablation confers social interaction deficits and perseverative behaviors in mouse models. However, it remains unknown to what extent DSCAM underexpression captures the full range of behaviors, specifically cognitive phenotypes, presented in ASD. Here, we conducted a comprehensive cognitive behavioral phenotyping which revealed that loss of one copy of DSCAM, as in the DSCAM2J+/−, that is, DSCAM heterozygous mice, displayed hyperactivity, increased anxiety‐like behavior, and motor coordination deficits. Additionally, hippocampal‐dependent learning and memory was affected, including impairments in working memory, long‐term memory, and contextual fear learning. Interestingly, implicit learning processes remained intact. Therefore, DSCAM LoF produces autistic‐like behaviors that are similar to those observed in human cases of ASD. These findings further support a role for DSCAM dnLoF mutations in ASD and suggest DSCAM2J+/− as a suitable model for ASD research.
It is estimated that 1 in 36 children are affected by autism spectrum disorder (ASD) in the United States, which is nearly a twofold increase from a decade ago. Recent genetic studies have identified de novo loss-of-function (dnLoF) mutations in the Down Syndrome Cell Adhesion Molecule (DSCAM) as a strong risk factor for ASD. Previous research has shown that DSCAM ablation confers social interaction deficits and perseverative behaviors in mouse models. However, it remains unknown to what extent DSCAM underexpression captures the full range of behaviors, specifically cognitive phenotypes, presented in ASD. Here, we conducted a comprehensive cognitive behavioral phenotyping which revealed that loss of one copy of DSCAM , as in the DSCAM 2J +/− mice, displayed hyperactivity, increased anxiety, and motor coordination impairments. Additionally, hippocampal-dependent learning and memory was affected, including working memory, long-term memory, and contextual fear learning. Interestingly, implicit learning processes remained intact. Therefore, DSCAM LoF produces autistic-like behaviors that are similar to human cases of ASD. These findings further support a role for DSCAM dnLoF mutations in ASD and suggest DSCAM 2J +/− as a suitable model for ASD research.
Summary Statement
Autism spectrum disorder represents a growing patient population. Loss of one copy of the DSCAM gene provides a promising mouse model that reproduces autistic-like behaviors for research and therapeutic testing.
Purpose
To summarize and appraise the emerging evidence on early motor skills of infants later diagnosed with autism spectrum disorder (ASD), and the association of early motor delays to later ASD diagnosis/characteristics.
Methods
A literature search was conducted for studies published from 2000 to 2023 on the motor skills of infants later diagnosed with ASD, followed by screening and data extraction.
Results
Current evidence suggested presence of early motor deficits including poor anticipatory movements, postural control, and gross/fine motor skills during the first 2 years of ASD. However, there was variability among studies with regard to study sample and methodology.
Conclusion
Although motor deficits are evident in infants, it is unclear whether these are specific to ASD or a consequence of general developmental disorder. Future research is needed on the investigation of specificity and severity of early motor delays, which can potentially assist in early identification of ASD.
Background:
Difficulties with praxis, the ability to perform learned skilled movements, have been robustly demonstrated in autism spectrum disorder (autism). However, praxis assessment is not routinely included in autism characterization batteries, in part because it is traditionally time consuming to administer and score. We test whether dyspraxia in autism can be captured with a brief measure.
Method:
Youth with autism (n = 41) and matched typically developing controls (n = 32), aged 8 to 16 years, completed a 5-minute praxis battery. The 19-item battery included four subtests: gesture to command, tool use, familiar imitation, and meaningless imitation. Video recordings were coded for error types and compared to participant characterization variables.
Results:
Consistent with research using a lengthy battery, autistic youth made more errors overall, with a large effect size. Groups demonstrated similar distributions of error types, suggesting that dyspraxia in autism is not limited to a particular error form. In the autism group, praxis was associated with adaptive functioning, but not autism traits.
Conclusions:
A shortened battery is sufficiently sensitive to praxis differences between autistic and typically developing youth, increasing the feasibility of including praxis within clinical assessments or larger research batteries aimed at testing relationships with downstream skills.
The present study aimed to synthesize and analyze the scientific production about the motor development (MD) characteristics in children with autistic spectrum
disorder (ASD) through systematic literature revision. In this sense, Eric/Thesaurus, Web of Science, SciELO, Scopus, ASP/EBscos and Redalyc databases were selected. For the articles' identification in the databases, the descriptors "child development", "autism spectrum disorder", "motor skills disorder" and "motor development" were listed, and their terms in portuguese as well. These descriptors were identified between the descriptors in health sciences (DiHS), BVS and Thesaurus (Eric) for embracing areas of health and education. The final sample was composed by five different studies that presented data from different motor assessment batteries. The results characterized the MD in children with ASD as atypical, presenting meaningful deficits in all the motor areas, being fine coordination, balance and body scheme the most talked about.
Transtorno do espectro autista (TEA) é um transtorno do neurodesenvolvimento que se manifesta na infância, apresentando alterações na morfologia, fisiologia, conectividade cerebral e ocasionando em distúrbios motores. Objetivo: avaliar o déficit de equilíbrio em crianças com transtorno do espectro autista em uma cidade localizada no interior do Rio Grande do Sul. Método: a amostra foi composta por 11 crianças com idade entre 3 e 14 anos, frequentadores de uma instituição de atendimento a autistas. Os participantes foram submetidos às seguintes avaliações: Bateria Psicomotora (BPM), Timed-up and Go Test e Tinetti. Resultados:[KC1] [AD2] observou-se predomínio do sexo masculino, redução estatisticamente significativa dos escores da escala de equilíbrio, (24,27 ±4,1; p=0,03) e escore total (13,45 ±2,5; p=0,022), sem diferença no escore da escala de marcha (10,82 ± 2,4 ; p=0,059), através da Escala de Equilíbrio e Mobilidade de Tinetti, e, na avaliação da BPM, 54,54% apresentaram perfil psicomotor normal. Nas correlações, encontrou-se relação direta entre o fator praxia global da BPM e escore total de Tinetti (r= 0,522[KC3] [AD4] ; p=0,05). Houve ainda relação entre os fatores psicomotores com o equilíbrio na BPM, sendo moderada para tonicidade (r= 0,582; p=0,03) e fortes entre noção do corpo (r=0,811; p=0,001), estruturação espaço temporal (r= 0,894; p=0,000), praxias global (r= 0,963; p=0,000) e fina (r=0,894; p=0,000). Em relação a análise dos fatores da BPM, a maioria dos pacientes apresentava dificuldade na praxia global, sendo 45,5% da amostra dispráxica. Foi possível ainda estabelecer correlação moderada entre a Praxia Global da BPM e o TUG (r=0,548, p=0,04) e, embora não significativa,com a Tinetti (r=0,522, p=0,05),. Foi observada também uma correlação moderada entre a Tonicidade e a TUG (R=0,601,p=0,025).Conclusão: crianças com TEA apresentam alteração no equilíbrio, representando um baixo risco de quedas, e comprometimento da praxia global, assim como uma correlação entre déficit de equilíbrio e alterações na tonicidade, noção do corpo, estruturação espaço temporal e praxias global e fina desses indivíduos.
It is perplexing that some preschool teachers not only advise parents who have children
with autism spectrum disorder (ASD) to go to religious healers, but also attribute such neurological
disorders to The curse of The “evil eye” or vaccines. Although it is now The twentieth century, this
behavior simply reflects The concerns of over-protective teachers and The cultural misperceptions
about The actual definition of ASD. In Yemen, The term “ASD”, with its wide range of symptoms,
is still ambiguous among preschool teachers. Thus, in a rather insightful piece for The education
community, this study has attempted to look beneath The surface of The beliefs (religious belief–social
belief–personal belief) of Yemeni preschool teachers regarding ASD. Based on The data collected from
213 teachers (20–30\31–40-~≥40 age) in The Taiz district, this study found that misconceptions specific
to autism spectrum disorder were strongly evidenced among teachers who taught preschoolers.
Due to personal ignorance and growing superstitions, these teachers tend to believe The society’s
perceptions of ASD, thus resulting in The ignorance of scientific views. However, The mass media
can increase this group’s awareness of ASD by continually assessing The inaccurate views on ASD,
and correcting them. And by influencing The teachers to take a more conceptual scientific approach
in serving their special needs students, furthermore, by informing preschool teachers of children’s rights in normal life in The future through providing children with an optimal chance of development
by early intervention.
Background
Motor skill deficits are prevalent among children with Autism Spectrum Disorder (ASD) however, little is known about the underlying mechanism of these deficits. In response to this gap, this study investigated how visual perception (VP) and visual-motor integration (VMI) are associated with motor skills among children and youth with ASD.
Methods
Sixty-seven individuals with ASD and sixty-seven age- and gender-matched individuals without ASD (age range: 9.83–15.13 years) participated. Motor skills were assessed with the Movement Assessment Battery for Children-2 (MABC-2) and VP and VMI with the respective components of the Beery-Buktenica Developmental Test of Visual-Motor Integration-6 (Beery VMI-6).
Results
Significantly more children and youth with ASD were in the red and orange zone of the MABC-2 traffic-lighting system for the total MABC-2 and the Aiming and Catching and Balance components compared to the children and youth without ASD. Both groups did not differ on the VP and VMI components of the Beery VMI-6. Pearson correlations between VP and VMI, and motor skills were weak but significant for the individuals without ASD, but not for the ASD group.
Conclusion
The current study added to the evidence about motor skill deficits among children and youth with ASD. VP and VMI were not related to motor skills, suggesting that these functions – as measured in the current study – are no underlying mechanisms of motor skill deficits of children with ASD and average intelligence. Diagnostic implications are provided for the evidence of motor skill deficits among children and youth with ASD.
As autistic adolescents and young adults navigate the transition to adulthood, there is a need to partner with them to identify strengths and needed supports to enable goal-directed actions. This article conceptually integrates research on self-determination, defined by Causal Agency Theory, and executive processes in autism to provide direction for future research and practice. We describe how integrating research on self-determination and executive processes could enable autistic adolescents and young adults to be engaged in the process of assessing executive processes and self-determination. We discuss how this can better inform personalization of supports for self-determination interventions by focusing on support needs related to executive processes, including inhibitory control and cognitive flexibility, from a strengths-based perspective. We discuss how this can enable self-determination interventions that promote outcomes aligned with the values of the autistic community.
A substantial body of evidence links differences in brain size to differences in brain organization. We have hypothesized that the developmental aspect of this relation plays a role in autism spectrum disorder (ASD), a neurodevelopmental disorder which involves abnormalities in brain growth. Children with ASD have abnormally large brains by the second year of life, and for several years thereafter their brain size can be multiple standard deviations above the norm. The greater conduction delays and cellular costs presumably associated with the longer long-distance connections in these larger brains is thought to influence developmental processes, giving rise to an altered brain organization with less communication between spatially distant regions. This has been supported by computational models and by findings linking greater intra-cranial volume, an index of maximum brain-size during development, to reduced inter-hemispheric connectivity in individuals with ASD. In this paper, we further assess this hypothesis via a whole-brain analysis of network efficiency. We utilize diffusion tractography to estimate the strength and length of the connections between all pairs of cortical regions. We compute the efficiency of communication between each network node and all others, and within local neighborhoods; we then assess the relation of these measures to intra-cranial volume, and the differences in these measures between adults with autism and typical controls. Intra-cranial volume is shown to be inversely related to efficiency for wide-spread regions of cortex. Moreover, the spatial patterns of reductions in efficiency in autism bear a striking resemblance to the regional relationships between efficiency and intra-cranial volume, particularly for local efficiency. The results thus provide further support for the hypothesized link between brain overgrowth in children with autism and the efficiency of the organization of the brain in adults with autism.
This study addressed what role movement timing irregularities have in producing the motor deficits documented in Asperger's Syndrome (AS). Participants included males with AS (n = 14) and without (n = 16), matched by age (7–23 years) and with no significant IQ differences. They completed measures of timing perception (comparisons of tempo of tones) and production (rhythmic finger tapping), and general motor skills (Dean–Woodcock Neuropsychological Battery motor tests). No central timing difficulties were noted, but the AS group showed more irregularity in motor implementation (with a large effect size), and this irregularity correlated with general motor skills.
Because sensation is delayed, real-time movement control requires not just sensing, but also predicting limb position, a function hypothesized for the cerebellum. Such cerebellar predictions could contribute to perception of limb position (i.e., proprioception), particularly when a person actively moves the limb. Here we show that human cerebellar patients have proprioceptive deficits compared with controls during active movement, but not when the arm is moved passively. Furthermore, when healthy subjects move in a force field with unpredictable dynamics, they have active proprioceptive deficits similar to cerebellar patients. Therefore, muscle activity alone is likely insufficient to enhance proprioception and predictability (i.e., an internal model of the body and environment) is important for active movement to benefit proprioception. We conclude that cerebellar patients have an active proprioceptive deficit consistent with disrupted movement prediction rather than an inability to generally enhance peripheral proprioceptive signals during action and suggest that active proprioceptive deficits should be considered a fundamental cerebellar impairment of clinical importance.
Both movement differences and disorders are common within autism spectrum disorders (ASD). These differences have wide and heterogeneous variability among different ages and sub-groups all diagnosed with ASD. Gait was studied in a more homogeneously identified group of nine teenagers and young adults who scored as "severe" in both measures of verbal communication and overall rating of Autism on the Childhood Autism Rating Scales (CARS). The ASD individuals were compared to a group of typically developing university undergraduates of similar ages. All participants walked a distance of 6-meters across a GAITRite (GR) electronic walkway for six trials. The ASD and comparison groups differed widely on many spatiotemporal aspects of gait including: step and stride length, foot positioning, cadence, velocity, step time, gait cycle time, swing time, stance time, and single and double support time. Moreover, the two groups differed in the percentage of the total gait cycle in each of these phases. The qualitative rating of "Body Use" on the CARS also indicated severe levels of unusual body movement for all of the ASD participants. These findings demonstrate that older teens and young adults with "severe" forms of Verbal Communication Impairments and Autism differ widely in their gait from typically developing individuals. The differences found in the current investigation are far more pronounced compared to previous findings with younger and/or less severely involved individuals diagnosed with ASD as compared to typically developing controls. As such, these data may be a useful anchor-point in understanding the trajectory of development of gait specifically and motor functions generally.
The cerebellar vermis (lobules VI-VII) has been implicated in both postmortem and neuroimaging studies of autism spectrum disorders (ASD). This region maintains the consistent accuracy of saccadic eye movements and plays an especially important role in correcting systematic errors in saccade amplitudes such as those induced by adaptation paradigms. Saccade adaptation paradigms have not yet been used to study ASD. Fifty-six individuals with ASD and 53 age-matched healthy controls performed an intrasaccadic target displacement task known to elicit saccadic adaptation reflected in an amplitude reduction. The rate of amplitude reduction and the variability of saccade amplitude across 180 adaptation trials were examined. Individuals with ASD adapted slower than healthy controls, and demonstrated more variability of their saccade amplitudes across trials prior to, during and after adaptation. Thirty percent of individuals with ASD did not significantly adapt, whereas only 6% of healthy controls failed to adapt. Adaptation rate and amplitude variability impairments were related to performance on a traditional neuropsychological test of manual motor control. The profile of impaired adaptation and reduced consistency of saccade accuracy indicates reduced neural plasticity within learning circuits of the oculomotor vermis that impedes the fine-tuning of motor behavior in ASD. These data provide functional evidence of abnormality in the cerebellar vermis that converges with previous reports of cellular and gross anatomic dysmorphology of this brain region in ASD.
It is widely accepted that we use contextual information to guide our gaze when searching for an object. People with autism spectrum disorder (ASD) also utilise contextual information in this way; yet, their visual search in tasks of this kind is much slower compared with people without ASD. The aim of the current study was to explore the reason for this by measuring eye movements. Eye movement analyses revealed that the slowing of visual search was not caused by making a greater number of fixations. Instead, participants in the ASD group were slower to launch their first saccade, and the duration of their fixations was longer. These results indicate that slowed search in ASD in contextual learning tasks is not due to differences in the spatial allocation of attention but due to temporal delays in the initial-reflexive orienting of attention and subsequent-focused attention. These results have broader implications for understanding the unusual attention profile of individuals with ASD and how their attention may be shaped by learning. Autism Res 2013, ●●: ●●-●●. © 2013 International Society for Autism Research, Wiley Periodicals, Inc.
Motor impairments have been found to be a significant clinical feature associated with autism and Asperger's disorder (AD) in addition to core symptoms of communication and social cognition deficits. Motor deficits in high-functioning autism (HFA) and AD may differentiate these disorders, particularly with respect to the role of the cerebellum in motor functioning. Current neuroimaging and behavioral evidence suggests greater disruption of the cerebellum in HFA than AD. Investigations of ocular motor functioning have previously been used in clinical populations to assess the integrity of the cerebellar networks, through examination of saccade accuracy and the integrity of saccade dynamics. Previous investigations of visually guided saccades in HFA and AD have only assessed basic saccade metrics, such as latency, amplitude, and gain, as well as peak velocity. We used a simple visually guided saccade paradigm to further characterize the profile of visually guided saccade metrics and dynamics in HFA and AD. It was found that children with HFA, but not AD, were more inaccurate across both small (5°) and large (10°) target amplitudes, and final eye position was hypometric at 10°. These findings suggest greater functional disturbance of the cerebellum in HFA than AD, and suggest fundamental difficulties with visual error monitoring in HFA.
Developmental Coordination Disorder (DCD) is a leading movement disorder in children that commonly involves poor postural control. Multisensory integration deficit, especially the inability to adaptively reweight to changing sensory conditions, has been proposed as a possible mechanism but with insufficient characterization. Empirical quantification of reweighting significantly advances our understanding of its developmental onset and improves the characterization of its difference in children with DCD compared to their typically developing (TD) peers.
Twenty children with DCD (6.6 to 11.8 years) were tested with a protocol in which visual scene and touch bar simultaneously oscillateded medio-laterally at different frequencies and various amplitudes. Their data were compared to data on TD children (4.2 to 10.8 years) from a previous study. Gains and phases were calculated for medio-lateral responses of the head and center of mass to both sensory stimuli. Gains and phases were simultaneously fitted by linear functions of age for each amplitude condition, segment, modality and group. Fitted gains and phases at two comparison ages (6.6 and 10.8 years) were tested for reweighting within each group and for group differences. Children with DCD reweight touch and vision at a later age (10.8 years) than their TD peers (4.2 years). Children with DCD demonstrate a weak visual reweighting, no advanced multisensory fusion and phase lags larger than those of TD children in response to both touch and vision.
Two developmental perspectives, postural body scheme and dorsal stream development, are provided to explain the weak vision reweighting. The lack of multisensory fusion supports the notion that optimal multisensory integration is a slow developmental process and is vulnerable in children with DCD.
Leo Kanner, an Austrian born American psychiatrist, first described autism in 1943 [1]. His observations of a small group
of children with behavioral symptoms of social withdrawal, impaired language/communication, and obsession with sameness led
to recognition of autism as a specific pervasive developmental disorder. At about the same time, Austrian psychiatrist Hans
Asperger independently described similar symptoms in a small group of children except that the “Asperger” children were high
functioning with better language and cognitive skills than those described by Kanner [2]. Both Kanner and Asperger used the
word autistic to describe the pathology in the children they observed – a term rooted in the Greek “autos” (self) and coined
by Swiss psychiatrist Eugen Bleuler to describe symptoms in his schizophrenic patients. Before Kanner and Asperger defined
autism as a specific disorder, children with autistic symptoms were most likely classed and treated as mentally retarded or,
if they were high functioning, perhaps as schizophrenic.
There has been significant advancement in various aspects of scientific knowledge concerning the role of cerebellum in the etiopathogenesis of autism. In the current consensus paper, we will observe the diversity of opinions regarding the involvement of this important site in the pathology of autism. Recent emergent findings in literature related to cerebellar involvement in autism are discussed, including: cerebellar pathology, cerebellar imaging and symptom expression in autism, cerebellar genetics, cerebellar immune function, oxidative stress and mitochondrial dysfunction, GABAergic and glutamatergic systems, cholinergic, dopaminergic, serotonergic, and oxytocin-related changes in autism, motor control and cognitive deficits, cerebellar coordination of movements and cognition, gene-environment interactions, therapeutics in autism, and relevant animal models of autism. Points of consensus include presence of abnormal cerebellar anatomy, abnormal neurotransmitter systems, oxidative stress, cerebellar motor and cognitive deficits, and neuroinflammation in subjects with autism. Undefined areas or areas requiring further investigation include lack of treatment options for core symptoms of autism, vermal hypoplasia, and other vermal abnormalities as a consistent feature of autism, mechanisms underlying cerebellar contributions to cognition, and unknown mechanisms underlying neuroinflammation.
Typical adults show an inverse relation between callosal fiber length and degree of interhemispheric connectivity. This has been hypothesized to be a consequence of the influence of conduction delays and cellular costs during development on axonal pruning, both of which increase with fiber length. Autism spectrum disorder (ASD) provides a test of this hypothesis: Children with ASD are known to have enlarged brains; thus, adults with ASD should show reductions in interhemispheric connectivity proportional to their degree of brain overgrowth during development. This prediction was tested by assessing the relation between both the size and structure of the corpus callosum and callosal fiber length, adjusting for intracranial volume, which is thought to reflect maximum brain size achieved during development. Using tractography to estimate the length of callosal fibers emanating from all areas of cortex, and through which region of the corpus callosum they pass, we show that adults with ASD show an inverse relation between callosal fiber length, adjusted for intracranial volume, and callosum size, and a positive relation between adjusted callosal fiber length and radial diffusivity. The results provide support for the hypothesized impact of fiber length during development. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
To explore the specificity of impaired praxis and postural knowledge to autism by examining three samples of children, including those with autism spectrum disorder (ASD), attention-deficit hyperactivity disorder (ADHD), and typically developing (TD) children.
Twenty-four children with ASD, 24 children with ADHD, and 24 TD children, ages 8-13, completed measures assessing basic motor control (the Physical and Neurological Exam for Subtle Signs; PANESS), praxis (performance of skilled gestures to command, with imitation, and tool use) and the ability to recognize correct hand postures necessary to perform skilled gestures (the Postural Knowledge Test; PKT).
Children with ASD performed significantly worse than TD children on all three assessments. In contrast, children with ADHD performed significantly worse than TD controls on PANESS but not on the praxis examination or PKT. Furthermore, children with ASD performed significantly worse than children with ADHD on both the praxis examination and PKT, but not on the PANESS.
Whereas both children with ADHD and children with ASD show impairments in basic motor control, impairments in performance and recognition of skilled motor gestures, consistent with dyspraxia, appear to be specific to autism. The findings suggest that impaired formation of perceptual-motor action models necessary to development of skilled gestures and other goal directed behavior is specific to autism; whereas, impaired basic motor control may be a more generalized finding.
To examine motor characteristics of children referred for evaluation for autism spectrum disorder (ASD) using the Bayley Scales of Infant and Toddler Development, Third Edition (BSID-III).
BSID-III scores were collected through retrospective chart review for 30 children (mean age = 31.57 ± 6 months) admitted to an outpatient autism evaluation clinic.
Children referred to an ASD clinic demonstrated a mean delay of 6 months for gross motor skills and 8 months for fine motor skills. There were no differences in total score or item analysis in group comparisons of motor characteristics in young children who did or did not receive a diagnosis of ASD.
These results suggest that a delay in fine and gross motor skills at an early age is a characteristic of infants referred to an ASD clinic. Furthermore, the BSID-III may not be sensitive enough to distinguish between referred children with and without ASD.
This study used the Movement Assessment Battery for Children (M-ABC2) to assess motor skills in children aged 7-10 years with autism (n = 18) in comparison to two groups of age-matched typically developing children; a receptive vocabulary matched group (n = 19) and a nonverbal IQ matched group (n = 22). The results supported previous work, as indicated by a significant general motor impairment in the group with autism. However, sub-analysis of the M-ABC2 revealed that there were only 2 out of 8 subcomponent skills which showed universal significant specific deficits for the autism group; i.e. catching a ball and static balance. These results suggest that motor skill deficits associated with autism may not be pervasive but more apparent in activities demanding complex, interceptive actions or core balance ability.
Considerable progress has been made in developing models of cerebellar function in sensorimotor control, as well as in identifying key problems that are the focus of current investigation. In this consensus paper, we discuss the literature on the role of the cerebellar circuitry in motor control, bringing together a range of different viewpoints. The following topics are covered: oculomotor control, classical conditioning (evidence in animals and in humans), cerebellar control of motor speech, control of grip forces, control of voluntary limb movements, timing, sensorimotor synchronization, control of corticomotor excitability, control of movement-related sensory data acquisition, cerebro-cerebellar interaction in visuokinesthetic perception of hand movement, functional neuroimaging studies, and magnetoencephalographic mapping of cortico-cerebellar dynamics. While the field has yet to reach a consensus on the precise role played by the cerebellum in movement control, the literature has witnessed the emergence of broad proposals that address cerebellar function at multiple levels of analysis. This paper highlights the diversity of current opinion, providing a framework for debate and discussion on the role of this quintessential vertebrate structure.
With increased interest in the early diagnosis and treatment of children with autism spectrum disorders (ASD), more attention has been called to the motor skills of very young children with ASD. This study describes the gross and fine motor skills of a cross-sectional group of 162 children with ASD between the ages of 12 and 36 months, as well as a subset of 58 children followed longitudinally. Gross motor and fine motor age equivalent scores were obtained for all children. A ‘motor difference’ variable was calculated for each child’s gross and fine motor skills by taking the absolute difference of the children’s age equivalent motor score and their respective chronological age. In Study 1 (the cross-sectional analysis), ANCOVA (co-varied for nonverbal problem solving) revealed significant group differences in the gross motor and fine motor age difference variables. Post-hoc analysis revealed that gross motor and fine motor differences became significantly greater with each 6-month period of chronological age. In Study 2, 58 children were measured twice, an average of 12 months apart. Results indicate that the gross motor and fine motor difference scores significantly increased between the first and second measurements. The importance of addressing motor development in early intervention treatments is discussed.
Autism spectrum disorders (ASDs) are the most common pediatric diagnoses in the United States. In this perspective article, we propose that a diverse set of motor impairments are present in children and adults with ASDs. Specifically, we will discuss evidence related to gross motor, fine motor, postural control, and imitation/praxis impairments. Moreover, we propose that early motor delays within the first 2 years of life may contribute to the social impairments of children with ASDs; therefore, it is important to address motor impairments through timely assessments and effective interventions. Lastly, we acknowledge the limitations of the evidence currently available and suggest clinical implications for motor assessment and interventions in children with ASDs. In terms of assessment, we believe that comprehensive motor evaluations are warranted for children with ASDs and infants at risk for ASDs. In terms of interventions, there is an urgent need to develop novel embodied interventions grounded in movement and motor learning principles for children with autism.
In the vanishing-ball illusion, the magician's social cues misdirect the audience's expectations and attention so that the audience "sees" a ball vanish in the air. Because individuals with autism spectrum disorder (ASD) are less sensitive to social cues and have superior perception for nonsocial details compared with typically developing individuals, we predicted that they would be less susceptible to the illusion. Surprisingly, the opposite result was found, as individuals with ASD were more susceptible to the illusion than a comparison group. Eye-tracking data indicated that subtle temporal delays in allocating attention might explain their heightened susceptibility. Additionally, although individuals with ASD showed typical patterns of looking to the magician's face and eyes, they were slower to launch their first saccade to the face and had difficulty in fixating the fast-moving observable ball. Considered together, the results indicate that individuals with ASD have difficulties in rapidly allocating attention toward both people and moving objects.
Apraxia traditionally refers to impaired ability to carry out skilled movements in the absence of fundamental sensorimotor, language, or general cognitive impairment sufficient to preclude them. The child neurology literature includes a much broader and varied usage of the term developmental dyspraxia. It has been used to describe a wide range of motor symptoms, including clumsiness and general coordination difficulties, in various developmental disorders (including autistic spectrum disorders, developmental language disorders, and perinatal stroke). We argue for the need to restrict use of the term developmental dyspraxia to describe impaired performance of skilled gestures, recognizing that, unlike acquired adult-onset apraxia, coexisting sensory and motor problems can also be present.
Various deficits in the cognitive functioning of people with autism have been documented in recent years but these provide only partial explanations for the condition. We focus instead on an imitative disturbance involving difficulties both in copying actions and in inhibiting more stereotyped mimicking, such as echolalia. A candidate for the neural basis of this disturbance may be found in a recently discovered class of neurons in frontal cortex, 'mirror neurons' (MNs). These neurons show activity in relation both to specific actions performed by self and matching actions performed by others, providing a potential bridge between minds. MN systems exist in primates without imitative and ‘theory of mind’ abilities and we suggest that in order for them to have become utilized to perform social cognitive functions, sophisticated cortical neuronal systems have evolved in which MNs function as key elements. Early developmental failures of MN systems are likely to result in a consequent cascade of developmental impairments characterised by the clinical syndrome of autism.
Children with autism often have difficulty performing skilled movements. Praxis performance requires basic motor skill, knowledge of representations of the movement (mediated by parietal regions), and transcoding of these representations into movement plans (mediated by premotor circuits). The goals of this study were (a) to determine whether dyspraxia in autism is associated with impaired representational ("postural") knowledge and (b) to examine the contributions of postural knowledge and basic motor skill to dyspraxia in autism. Thirty-seven children with autism spectrum disorder (ASD) and 50 typically developing (TD) children, ages 8-13, completed (a) an examination of basic motor skills, (b) a postural knowledge test assessing praxis discrimination, and (c) a praxis examination. Children with ASD showed worse basic motor skill and postural knowledge than did controls. The ASD group continued to show significantly poorer praxis than did controls after accounting for age, IQ, basic motor skill, and postural knowledge. Dyspraxia in autism appears to be associated with impaired formation of spatial representations, as well as transcoding and execution. Distributed abnormality across parietal, premotor, and motor circuitry, as well as anomalous connectivity, may be implicated.
Children with autism spectrum disorder (ASD) have deficits in motor control, imitation and social function. Does a dysfunction in the neural basis of representing internal models of action contribute to these problems? We measured patterns of generalization as children learned to control a novel tool and found that the autistic brain built a stronger than normal association between self-generated motor commands and proprioceptive feedback; furthermore, the greater the reliance on proprioception, the greater the child's impairments in social function and imitation.
Impairments in executive cognitive control, including a reduced ability to inhibit prepotent responses, have been reported in autism spectrum disorders (ASD). These deficits may underlie patterns of repetitive behaviors associated with the disorder.
Eighteen individuals with ASD and 15 age- and IQ-matched healthy individuals performed an antisaccade task and a visually guided saccade control task, each with gap and overlap conditions. Measures of repetitive behaviors were obtained using the Autism Diagnostic Inventory-Revised (ADI-R) and examined in relation to neurocognitive task performance.
Individuals with an ASD showed increased rates of prosaccade errors (failures to inhibit prepotent responses) on the antisaccade task regardless of task condition (gap/overlap). Prosaccade error rates were associated with the level of higher-order (e.g. compulsions, preoccupations) but not sensorimotor repetitive behaviors in ASD.
Neurocognitive disturbances in voluntary behavioral control suggest that alterations in frontostriatal systems contribute to higher-order repetitive behaviors in ASD.
• Kinesiologic analysis of the gaits of 21 autistic, 15 normal, and five hyperactive-aggressive children revealed that the autistic patients had (a) reduced stride lengths, (b) increased stance times, (c) increased hip flexion at "toe-off," and (d) decreased knee extension and ankle dorsiflexion at ground contact. In many respects, the gait differences between the autistic and normal subjects resembled differences between the gaits of parkinsonian patients and of normal adults. These preliminary results are compatible with the view that the autistic syndrome may be associated with specific dysfunction of the motor system affecting, among other structures, the basal ganglia.
The earliest observable symptoms of autism spectrum disorders (ASDs) involve motor behavior. There is a growing awareness of the developmental importance of impaired motor function in ASD and its association with social skill. Compromised motor function requires increased attention, leaving fewer resources available for processing environmental stimuli and learning. This knowledge suggests that the motor system-which we know to be trainable-may be a gateway to improving outcomes of individuals living with ASD. In this review, we suggest a framework borrowed from machine learning to examine where, why, and how motor skills are different in individuals with ASD.
We investigated eye-hand coordination in children with autism spectrum disorders (ASD) in comparison with age-matched normally developing peers. The eye-hand correlation was measured by putting fixation latencies in relation with pointing and key pressing responses in visual detection tasks where a gap-overlap paradigm was used and compared to fixation latencies in absence of manual response. ASD patients showed less efficient eye-hand coordination, which was particularly evident when pointing towards a target was being fixated. The data of normally developing participants confirmed that manual gap effects are more likely for more complex hand movements. An important discrepancy was discovered in participants with ASD: beside normal eye gap effects, they showed no concurrent hand gap effects when pointing to targets. This result has been interpreted as a further sign of inefficient eye-hand coordination in this patient population.
The dominant view of cerebellar function has been that it is exclusively concerned with motor control and coordination. Recent findings from neuroanatomical, behavioral, and imaging studies have profoundly changed this view. Neuroanatomical studies using virus transneuronal tracers have demonstrated that cerebellar output reaches vast areas of the neocortex, including regions of prefrontal and posterior parietal cortex. Furthermore, it has recently become clear that the cerebellum is reciprocally connected with the basal ganglia, which suggests that the two subcortical structures are part of a densely interconnected network. Taken together, these findings elucidate the neuroanatomical substrate for cerebellar involvement in non-motor functions mediated by the prefrontal and posterior parietal cortex, as well as in processes traditionally associated with the basal ganglia.
Background:
Motor delays have been reported in retrospective studies of young infants who later develop Autism Spectrum Disorders (ASDs).
Objective:
In this study, we prospectively compared the gross motor development of a cohort at risk for ASDs; infant siblings of children with ASDs (AU sibs) to low risk typically developing (LR) infants.
Methods:
24 AU sibs and 24 LR infants were observed at 3 and 6 months using a standardized motor measure, the Alberta Infant Motor Scale (AIMS). In addition, as part of a larger study, the AU sibs also received a follow-up assessment to determine motor and communication performance at 18 months using the Mullen Scales of Early Learning.
Results:
Significantly more AU sibs showed motor delays at 3 and 6 months than LR infants. The majority of the AU sibs showed both early motor delays and later communication delays.
Limitations:
Small sample size and limited follow-up.
Conclusions:
Early motor delays are more common in AU sibs than LR infants. Communication delays later emerged in 67-73% of the AU sibs who had presented with early motor delays. Overall, early motor delays may be predictive of future communication delays in children at risk for autism.
A study was designed to test 2 alternative hypotheses—a symbolic hypothesis and an executive function hypothesis—for the imitation and pantomime deficits found in previous studies of autism. The subjects were 17 adolescent high-functioning subjects with autism spectrum disorders and 15 clinical comparison subjects who were matched on chronological age and verbal IQ. Meaning and sequence were manipulated in facial and manual imitation tasks. Sequence was manipulated in the pantomime and control tasks. Recognition memory and motor control tasks were matched to the experimental tasks. The results provided no support for the symbolic deficit hypothesis; meaning aided rather than hindered the performance of the group with autism. Partial support for the executive deficit hypothesis was found. There were no group differences on motor control tasks, and few on the memory control tasks, arguing against deficits in motor initiation, basic motor coordination, or visual recognition memory.
Although autism is usually characterized with respect to sociocommunicative impairments, visual search is known as a domain of relative performance strength in this disorder. This study used functional MRI during visual search in children with autism spectrum disorder (n = 19; mean age = 13;10) and matched typically developing children (n = 19; mean age = 14;0). We selected regions of interest within two attentional networks known to play a crucial role in visual search processes, such as goal-directed selective attention, filtering of irrelevant distractors, and detection of behaviorally-relevant information, and examined activation and connectivity within and between these attentional networks. Additionally, based on prior research suggesting links between visual search abilities and autism symptomatology, we tested for correlations between sociocommunicative impairments and behavioral and neural indices of search. Contrary to many previous functional connectivity magnetic resonance imaging studies of autism that reported functional underconnectivity for task domains of weakness, we found atypically increased connectivity within and between attentional networks in autism. Additionally, we found increased functional connectivity for occipital regions, both locally and for long-distance connections with frontal regions. Both behavioral and neural indices of search were correlated with sociocommunicative impairment in children with autism. This association suggests that strengths in nonsocial visuospatial processing may be related to the development of core autistic sociocommunicative impairments. Hum Brain Mapp , 2012. © 2012 Wiley Periodicals, Inc.
The brain builds an association between action and sensory feedback to predict the sensory consequence of self-generated motor commands. This internal model of action is central to our ability to adapt movements and may also play a role in our ability to learn from observing others. Recently, we reported that the spatial generalization patterns that accompany adaptation of reaching movements were distinct in children with autism spectrum disorder (ASD) as compared with typically developing (TD) children. To test whether the generalization patterns are specific to ASD, here, we compared the patterns of adaptation with those in children with attention deficit hyperactivity disorder (ADHD). Consistent with our previous observations, we found that in ASD, the motor memory showed greater than normal generalization in proprioceptive coordinates compared with both TD children and children with ADHD; children with ASD also showed slower rates of adaptation compared with both control groups. Children with ADHD did not show this excessive generalization to the proprioceptive target, but they did show excessive variability in the speed of movements with an increase in the exponential distribution of responses (τ) as compared with both TD children and children with ASD. The results suggest that slower rate of adaptation and anomalous bias towards proprioceptive feedback during motor learning are characteristics of autism, whereas increased variability in execution is a characteristic of ADHD.
Physical therapists have expanded their role and visibility in the treatment of children with autism spectrum disorders (ASD). Limitations in motor activity have not been considered in the assessments of core deficits of this population; however, physical therapists should be prepared to discuss and address these limitations in children with ASD.
The primary purposes of this review were to summarize current evidence for motor activity limitations in children with ASD and suggest further areas of research in physical therapy and autism while considering how physical therapy may benefit children with autism.
A literature search was carried out in 2009 and 2010 by using multiple search engines.
Forty-nine articles met inclusion criteria and were included in the review.
Findings indicate that limitations in motor activity may be present in individuals with ASD, and further research is needed to identify specific functional limitations.
This paper examines the upper-limb movement kinematics of young children (3-7 years) with high-functioning autism using a point-to-point movement paradigm. Consistent with prior findings in older children, a difference in movement preparation was found in the autism group (n = 11) relative to typically developing children. In contrast to typically developing children, the presence of a visual distractor in the movement task did not appear to impact on early movement planning or execution in children with autism, suggesting that this group were not considering all available environmental cues to modulate movement. The findings from this study are consistent with the possibility that autism is associated with a difficulty using visual information to prime alternative movements in a responsive way to environmental demands.
Autism spectrum disorders (ASDs) are heterogeneous neurodevelopmental disorders associated with various co-morbidities. Neurological co-morbidities include motor impairments, epilepsy, and sleep dysfunction. These impairments have been receiving more attention recently, perhaps because of their significant impact on the behavior and cognitive function of children with ASDs. Here, we review the epidemiology, etiology, and clinical approach to these neurological co-morbidities and highlight future research directions.
Motor impairments include stereotypies, motor delays, and deficits, such as dyspraxia, incoordination, and gait problems. Sleep dysfunction typically presents as difficulty with sleep onset and prolonged awakenings during the night. Recent data suggest that abnormalities in melatonin may affect sleep and may be a potential treatment target. There is no classic epilepsy syndrome associated with ASDs. Intellectual disability, syndromic autism, and female sex are specific risk factors. Recent research has focused on identifying the overlapping pathways between these neurological co-morbidities and the core deficits in ASDs, which may have direct and powerful implications for treatment and prognosis.
Motor impairment, epilepsy, and sleep dysfunction are common neurological co-morbidities in ASDs. Clinicians should be aware that recognition and treatment of these issues may improve the function and outcome of children with ASDs.
Anatomical, clinical and imaging findings suggest that the cerebellum is engaged in cognitive and affective functions as well as motor control. Evidence from converging modalities also indicates that there is a functional topography in the human cerebellum for overt control of movement vs. higher functions, such that the cerebellum can be divided into zones depending on connectivity with sensorimotor vs. multimodal association cortices. Using functional MRI, we show that regions active during overt movement differ from those involved in higher-level language, spatial processing and working memory tasks. Nine healthy participants each completed five tasks in order to determine the relative activation patterns for the different paradigms. Right-handed finger-tapping activated right cerebellar lobules IV-V and VIII, consistent with descriptions of the cerebellar homunculi. Verb generation engaged right cerebellar lobules VI-Crus I and a second cluster in lobules VIIB-VIIIA. Mental rotation activation peaks were localized to medial left cerebellar lobule VII (Crus II). A 2-back working memory task activated bilateral regions of lobules VI-VII. Viewing arousing vs. neutral images did not reliably activate the cerebellum or cerebral limbic areas in this study. The cerebellar functional topography identified in this study reflects the involvement of different cerebro-cerebellar circuits depending on the demands of the task being performed: overt movement activated sensorimotor cortices along with contralateral cerebellar lobules IV-V and VIII, whereas more cognitively demanding tasks engaged prefrontal and parietal cortices along with cerebellar lobules VI and VII. These findings provide further support for a cerebellar role in both motor and cognitive tasks, and better establish the existence of functional subregions in the cerebellum. Future studies are needed to determine the exact contribution of the cerebellum - and different cerebro-cerebellar circuits - to task performance.
Internal action models refer to sensory-motor programs that form the brain basis for a wide range of skilled behavior and for understanding others' actions. Development of these action models, particularly those reliant on visual cues from the external world, depends on connectivity between distant brain regions. Studies of children with autism reveal anomalous patterns of motor learning and impaired execution of skilled motor gestures. These findings robustly correlate with measures of social and communicative function, suggesting that anomalous action model formation may contribute to impaired development of social and communicative (as well as motor) capacity in autism. Examination of the pattern of behavioral findings, as well as convergent data from neuroimaging techniques, further suggests that autism-associated action model formation may be related to abnormalities in neural connectivity, particularly decreased function of long-range connections. This line of study can lead to important advances in understanding the neural basis of autism and, more critically, can be used to guide effective therapies targeted at improving social, communicative, and motor function.
This review will focus on the possibility that the cerebellum contains an internal model or models of the motor apparatus. Inverse internal models can provide the neural command necessary to achieve some desired trajectory. First, we review the necessity of such a model and the evidence, based on the ocular following response, that inverse models are found within the cerebellar circuitry. Forward internal models predict the consequences of actions and can be used to overcome time delays associated with feedback control. Secondly, we review the evidence that the cerebellum generates predictions using such a forward model. Finally, we review a computational model that includes multiple paired forward and inverse models and show how such an arrangement can be advantageous for motor learning and control.
The neural substrates of eye movement measures are largely known. Therefore, measurement of eye movements in psychiatric disorders may provide insight into the underlying neuropathology of these disorders. Visually guided saccades, antisaccades, memory guided saccades, and smooth pursuit eye movements will be reviewed in various childhood psychiatric disorders. The four aims of this review are (1) to give a thorough overview of eye movement studies in a wide array of psychiatric disorders occurring during childhood and adolescence (attention-deficit/hyperactivity disorder, oppositional deviant disorder and conduct disorder, autism spectrum disorders, reading disorder, childhood-onset schizophrenia, Tourette's syndrome, obsessive compulsive disorder, and anxiety and depression), (2) to discuss the specificity and overlap of eye movement findings across disorders and paradigms, (3) to discuss the developmental aspects of eye movement abnormalities in childhood and adolescence psychiatric disorders, and (4) to present suggestions for future research. In order to make this review of interest to a broad audience, attention will be given to the clinical manifestation of the disorders and the theoretical background of the eye movement paradigms.
We analyze the behavioral and motor disturbances in childhood autism. On the basis of analogy to signs and conditions seen in adult neurology, we propose that the syndrome results from dysfunction in a system of bilateral neural structures that includes the ring of mesolimbic cortex located in the mesial frontal and temporal lobes, the neostriatum, and the anterior and medial nuclear groups of the thalamus. The mesolimbic cortex is cytoarchitectonically, angioarchitectonically, and neurochemically distinct and, along with the striatum, forms the entire target area of dopaminergic mesencephalic neurons. This raises the possibility that autism is related to neuromediator imbalance in those structures. Such dysfunction might be the result of macroscopic or microscopic changes in the target area or in structures functionally influencing them, consequent to a variety of causes such as perinatal viral infection, insult to the periventricular watershed area, or genetically determined neurochemical abnormalities.
Since its initial description in 1943,1 autism has been primarily conceptualized as a behavioral disorder, and for many years it was believed to be the result of parental and environmental influences. With heightened clinical interest in the disorder, coincident with advances in medical technology, however, evidence for an underlying neurologic basis for autism has become increasingly apparent.
HISTORICAL NEUROPATHOLOGIC PERSPECTIVE
Based largely on the constellation of symptoms that characterize the disorder, various anatomical sites within the brain have been suggested as a possible primary source of pathology in autism. Suspected regions have included the medial temporal lobe,2-5 the thalamic nuclei,6 the basal ganglia,7 and the vestibular system.8 Computed tomographic imaging studies have shown inconsistent findings.9-14 More recently, however, magnetic resonance imaging studies have described abnormalities in portions of the cerebellum and posterior fossa.15-17
Direct microscopic examination of the autistic brain has, until recently, yielded little information. Aarkrog18 reported "slight thickening of the arterioles, slight connective tissue increase in the leptomeninges, and some cell increase" in a frontal lobe biopsy performed on an autistic patient. Later, in 1976, 33 cases of childhood psychosis were reviewed by Darby.19 Although he suggested a possible correlation between limbic system lesions and the affective symptomatology of autism, no consistent neuropathologic findings were found. In 1980, Williams et al20 studied sections of brain from four patients with autistic-like behavior; looking primarily for cell loss and gliosis, they failed to find any consistent abnormalities.
MICROSCOPIC NEUROANATOMIC OBSERVATIONS
In 1984, anatomic abnormalities were reported in the brain of a 29-year-old man with well-documented autism; the technique of whole brain serial section was used, and the patient was studied in comparison with an identically processed age- and sex-matched control subject.21,22
This research extends previous research regarding the intellectual functioning of autistic individuals on standardized measures of intelligence (Wechsler Adult Intelligence Scale-Revised and the Wechsler Intelligence Scale for Children-Revised). In Study I 33 individuals with autism who closely fit the DSM-III criteria were studied. Clear evidence was found that differentiates these individuals' verbal intellectual processes from their visual-motor intellectual abilities. Principal components analysis was used to examine the interrelationship among the various intellectual abilities which such tests of intelligence measure. In Study II the intellectual abilities of a group of autistic 8- to 12-year-olds were compared to age-matched groups of children with receptive developmental language disorder, dysthymic disorder, or oppositional disorder. The intellectual abilities of autistic children were significantly different from the other groups of children.