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Abstract

Behavioural and neurophysiological evidence suggest that vision plays an important role in the emergence and development of arithmetic abilities. However, how visual deprivation impacts on the development of arithmetic processing remains poorly understood. We compared the performances of early, late blind and sighted control individuals during various arithmetic tasks involving addition, subtraction and multiplication of various complexities. We also assessed working memory (WM) performances to determine if they relate to a blind person’s arithmetic capacities. Results showed that early blind participants performed better than late blind and sighted controls in arithmetic tasks, especially in conditions in which verbal routines and WM abilities are needed. Moreover, early blind participants also showed higher WM abilities. Together, our findings demonstrate that the absence of developmental vision does not prevent the development of refined arithmetic skills and can even trigger the refinement of these abilities in specific tasks.

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... Consistent with previous studies, blind participants performed significantly better then sighted participants on the working memory task (blind: 63.99%, SD = 15.50; sighted: 48.66%, SD = 8.17; unpaired t-test: t(36) = 3.51, p = 0.001) (Amedi et al., 2003;Crollen, Mahe, Collignon, & Seron, 2011;Dormal, Crollen, Baumans, Lepore, & Collignon, 2016;Occelli, Lacey, Stephens, Sathian, &, Rehabilitation, 2016;Raz et al., 2007). Working memory was correlated with subtraction performance in both the blind (R 2 = 0.34, p = 0.003) and sighted groups (R 2 = 0.66, p < 0.001), to the same extent (Fisher r to z transformation, z = −1.31, ...
... It is unclear why changes to ANS precision would affect performance with large but not small numbers. One possibility is that performance on larger number sequences is more dependent on working memory abilities, which are enhanced in individuals who are blind (Amedi et al., 2003;Dormal et al., 2016;Occelli et al., 2016;Raz et al., 2007). The available data are thus most consistent with the hypothesis that the ANS is neither specialized for a particular modality nor for a particular input format (sequential versus simultaneous). ...
... However, the relationship between the ANS and symbolic math persisted even when working memory performance was factored out. In addition, we replicated previous findings that congenitally blind individuals have superior verbal working memory, relative to sighted individuals, as measured by participants' forward and backward letter spans (Amedi et al., 2003;Dormal et al., 2016;Occelli et al., 2016;Raz et al., 2007). Working memory advantages associated with blindness can be traced back to childhood: blind children between the ages of 7 and 13 are better at remembering lists of pseudo-words than sighted children (Crollen et al., 2011). ...
... Blind people appeared to behave similarly in tasks involving the haptic exploration of a rod in order to indicate its midpoint, while listening to a particular number (Cattaneo, Fantino, Tinti, Silvanto, & Vecchi, 2010). Blind people also showed the same subitizing range as their sighted peers (Ferrand, Riggs, & Castronovo, 2010) and, perhaps more surprisingly, even demon strated better numerosity estimation (Castronovo & Delvenne, 2013;Castronovo & Seron, 2007;Ferrand et al., 2010;Togoli, Crollen, Arrighi, & Collignon, 2020), counting (Crollen et al., 2014) and calculation skills (Dormal, Crollen, Baumans, Lepore, & Collignon, 2016) as compared to a matched sighted group. Altogether, these results therefore support the idea that numerical skills can emerge despite a lack of visual experience. ...
... Despite this strategy difference, blind and sighted children achieved a similar counting performance, suggesting that the use of fingers is not mandatory to achieve optimal performance in counting. Blind children finally showed better arithmetic performances (more correct responses coupled with smaller reaction times) than sighted children (see Dormal et al., 2016 for similar results in adults) in all the operations tested (addition, subtraction, multiplication). Our results therefore suggest that vision is not mandatory for the emergence of good arithmetic and basic numerical skills in children. ...
... Regarding the working memory data, we observed that blind children outperformed their sighted peers on all the verbal memory tasks (both on the simple and on the complex span tasks). In contrast, the groups did not differ significantly on the spatial task, similarly to what has already been observed with adults (Castronovo & Delvenne, 2013;Dormal et al., 2016;Occelli, Lacey, Stephens, Merabet, & Sathian, 2017). Interestingly, while the sighted showed a larger spatial span when performing the task in their dominant visual modality, there was no difference between the blind tactile span and the sighted visual one. ...
Preprint
Studies involving congenitally blind adults demonstrated that visual experience is not a mandatory prerequisite for the emergence of efficient numerical abilities. It remains however unknown whether blind adults developed lifelong strategies to compensate for the absence of foundations vision would provide in infancy. We therefore assessed basic numerical abilities in blind and sighted children of 6 to 13 years old. We also assessed verbal and spatial working memory abilities and their relationship with mental arithmetic in both groups. Blind children showed similar or better numerical abilities as compared to the sighted. Blind children also outperformed their sighted peers in every task assessing verbal working memory and demonstrated a similar spatial span. The correlation between arithmetic and the spatial sketchpad was affected by the group while the correlations between arithmetic and the other two components (the central executive and the phonological loop) were not affected by early visual experience. Our data suggest that early blindness does not impair the development of basic numerical competencies in children but influences the associations between arithmetic and some working memory components.
... Blind people appeared to behave similarly in tasks involving the haptic exploration of a rod in order to indicate its midpoint, while listening to a particular number (Cattaneo, Fantino, Tinti, Silvanto, & Vecchi, 2010). Blind people also showed the same subitizing range as their sighted peers (Ferrand, Riggs, & Castronovo, 2010) and, perhaps more surprisingly, even demonstrated better numerosity estimation (Castronovo & Delvenne, 2013;Castronovo & Seron, 2007;Ferrand et al., 2010;Togoli, Crollen, Arrighi, & Collignon, 2020), counting (Crollen et al., 2014) and calculation skills (Dormal, Crollen, Baumans, Lepore, & Collignon, 2016) as compared to a matched sighted group. Altogether, these results therefore support the idea that numerical skills can emerge despite a lack of visual experience. ...
... Despite this strategy difference, blind and sighted children achieved a similar counting performance, suggesting that the use of fingers is not mandatory to achieve optimal performance in counting. Blind children finally showed better arithmetic performances (more correct responses coupled with smaller reaction times) than sighted children (see Dormal et al., 2016 for similar results in adults) in all the operations tested (addition, subtraction, multiplication). Our results therefore suggest that vision is not mandatory for the emergence of good arithmetic and basic numerical skills in children. ...
... Regarding the working memory data, we observed that blind children outperformed their sighted peers on all the verbal memory tasks (both on the simple and on the complex span tasks). In contrast, the groups did not differ significantly on the spatial task, similarly to what has already been observed with adults (Castronovo & Delvenne, 2013;Dormal et al., 2016;Occelli, Lacey, Stephens, Merabet, & Sathian, 2017). Interestingly, while the sighted showed a larger spatial span when performing the task in their dominant visual modality, there was no difference between the blind tactile span and the sighted visual one. ...
Article
Studies involving congenitally blind adults shows that visual experience is not a mandatory prerequisite for the emergence of efficient numerical abilities. It remains however unknown whether blind adults developed lifelong strategies to compensate for the absence of foundations vision would provide in infancy. We therefore assessed basic numerical abilities in blind and sighted children of 6 to 13 years old. We also assessed verbal and spatial working memory abilities and their relationship with mental arithmetic in both groups. Blind children showed similar or better numerical abilities as compared to the sighted. Blind children also outperformed their sighted peers in every task assessing verbal working memory and demonstrated a similar spatial span. The correlation between arithmetic and the spatial sketchpad was stronger in blind relative to sighted children while the correlations between arithmetic and the other two components (the central executive and the phonological loop) were not affected by early visual experience. Our data suggest that early blindness does not impair the development of basic numerical competencies in children but influences the associations between arithmetic and some working memory subcomponents.
... Similarly, blindness was shown to affect the nature of the spatial reference frame in which the spatial processing of numbers occurs (Crollen, Dormal, Seron, Lepore, & Collignon, 2013). Despite these qualitative differences, blind adults nevertheless present similar (Crollen et al., 2013(Crollen et al., , 2014 or even better (Castronovo & Delvenne, 2013;Dormal, Crollen, Baumans, Lepore, & Collignon, 2016) numerical performances than their sighted peers. To explain this observation, it was recently suggested that blind people may develop mathematical understanding by mostly relying on haptic manipulation (Crollen, Collignon, & Noël, 2017). ...
... Following the observation that blind individuals do not use their fingers to learn counting and calcultae (Crollen et al., 2011(Crollen et al., , 2014) but nevertheless present similar or even better numerical performance than their sighted peers (Castronovo & Delvenne, 2013;Castronovo & Seron, 2007;Dormal et al., 2016;Ferrand, Riggs, & Castronovo, 2010), we suggested that haptic manipulation could engage children in some cognitive reasoning which are beneficial to arithmetic learning. By conducting an intervention study, we were able to evaluate the functional relationship that exists between haptic manipulation and arithmetic learning. ...
Preprint
Recent studies suggested that multisensory training schemes could boost the development of abstract concepts. In the present study, we wanted to evaluate whether training arithmetic with a multisensory intervention could induce larger learning improvements than a visual intervention alone. Moreover, as a left-to-right oriented mental number line was for a long time considered as a core feature of numerical representation, we also wanted to compare left-to-right and non-linear arithmetic training. In order to do so, kindergarten children were trained to solve simple addition and subtraction operations. Four training-conditions were created according to two factors: the perceptual modalities (multisensory vs. visual) and the spatial disposition of the materials used (linear vs. non-linear). While the effect of spatial disposition was not highlighted in the arithmetic task, the multisensory training method induced a larger improvement of arithmetic performance as compared to the visual training alone. These results support the idea that haptic manipulation provides a bridge between concrete referents and abstract concepts.
... However, the fact that similar regions activate in blind and sighted individuals during the same specific task (i.e., parietal network during subtraction) does not guarantee that the specific format of the cognitive operation is similar across both groups. Indeed, if the lack of vision does not preclude the optimal development of various numerical skills (Dormal et al., 2016b;Castronovo, 2014;Crollen and Collignon, 2016), some qualitative properties of numerical representations do seem to critically depend on early visual experience. For example, congenital blindness changes the nature of the reference frame in which the spatial processing of numbers occurs: while sighted and late blind participants associate numbers to an external frame of reference, CB individuals principally rely on an association between numbers and an egocentric coordinate system (Crollen et al., 2013). ...
... Similarly, average size , line length (Cappelletti et al., 2014;De Visscher et al., 2017) and area (Iuculano et al., 2008) are not impaired by dyscalculia, a learning deficit affecting number processing. The evidence that numerical concepts can be acquired in CB raise the question as to whether these perceptual factors that link to the development of arithmetic abilities in the sighted are independent from visual experience or whether, in contrast, CB people rely on separate perceptual processes in order to develop adequate arithmetic abilities through separate cognitive mechanisms (Dormal et al., 2016b;Crollen et al., 2017). ...
... Individuals with blindness presented similar accuracy levels in all the tasks described above. They perform even better than sighted in various numerosity estimation tasks (Castronovo & Delvenne, 2013;Castronovo & Seron, 2007b;Ferrand, Riggs, & Castronovo, 2010) and in some calculation experiments involving addition and multiplication operations (Dormal, Crollen, Baumans, Lepore, & Collignon, 2016). Vision is therefore not mandatory for the emergence of numerical-spatial interactions, even though visual experience affects the nature of this relation (Crollen & Collignon, 2012). ...
... Second, the use of damaged visuo-spatial processes seems to have more negative impact on numerical abilities than the total absence of visuo-spatial processes at birth (when comparing people with low visuospatial abilities, NVLD or WS to the individuals with blindness). Indeed, it is interesting to note that people with blindness were shown to present similar (Castronovo & Seron, 2007a;Crollen et al., 2013Crollen et al., , 2014 or even better (Castronovo & Delvenne, 2013;Castronovo & Seron, 2007b;Dormal et al., 2016) numerical performances than their sighted peers in a series of numerical tasks. This observation, coupled with the fact that even infants with WS present relative strengths on some numerical tasks (Ansari et al., 2003;O'Hearn et al., 2011), suggest that the numerical system is flexible enough to rely on different kinds of sensory and cognitive strategies to develop. ...
Article
In the past few years, the role of both domain-specific and domain-general factors on numerical development and mathematics achievement has been debated. In this paper, we focus on the role of visuo-spatial processes. We will more particularly review the numerical abilities of populations presenting atypical visuo-spatial processes: individuals with blindness, hemineglect, children presenting low visuo-spatial abilities, non-verbal learning disorder or Williams syndrome. We will show that math abilities of each population are relatively unique and are not necessarily associated with generalized math impairment. We will show that a better understanding of the strengths and weaknesses of each population gives further insights into our conceptual understanding of the development of numerical cognition. We will finally demonstrate how the comparison across disorders can impact on practical rehabilitation and educational strategies.
... One higher-cognitive domain in which blind individuals are known to show an advantage is memory. Blind children and adults recall larger numbers of words, letters and digits over both short and long delays and more accurately reproduce the serial order of encoded words (Amedi, Raz, Pianka, Malach, & Zohary, 2003;Dormal, Crollen, Baumans, Lepore, & Collignon, 2016;Hull & Mason, 1995;Pasqualotto, Lam, & Proulx, 2013;Raz, Striem, Pundak, Orlov, & Zohary, 2007;Roder, Rösler, & Neville, 2001;Rokem & Ahissar, 2009;Swanson & Luxenberg, 2009;Tillman & Bashaw, 1968;Withagen, Kappers, Vervloed, Knoors, & Verhoeven, 2013). Analogous to improvements observed in audition and touch, improvement in memory may result from compensatory reliance on memory in the absence of visual cues together with availability of extra "visual" cortex wetware (Raz, Striem, Pundak, Orlov, & Zohary, 2007). ...
... While blind individuals show improved behavior on some tasks that activate "visual" cortices this is not uniformly the case. For example, blind individuals activate "visual" cortices when solving math equations and outperform the sighted on some memory intensive arithmetic tasks (Dormal et al., 2016). However, for many math tasks, including those that activate "visual" cortex in blindness, there are no blindness-related advantages (e.g. ...
Article
People born blind habitually experience linguistic utterances in the absence of visual cues. Neuroimaging evidence suggests that congenitally blind individuals also activate “visual” cortices during sentence comprehension. Do blind individuals show superior performance on sentence processing tasks? Congenitally blind (n = 25) and age and education matched sighted (n = 52) participants answered yes/no who-did-what-to-whom questions for auditorily presented sentences, some of which contained a grammatical complexity manipulation (long-distance movement dependency or garden path). Short-term memory was measured with a forward and backward letter-span task. A battery of control tasks included two speeded math tasks and vocabulary and reading tasks from Woodcock Johnson III. The blind group outperformed the sighted group on the sentence comprehension task, particularly for garden-path sentences, and on short-term memory span tasks, but performed similar to the sighted group on control tasks. Sentence comprehension performance was not correlated with working memory span performance, suggesting independent enhancements.
... None of these studies concerned body odor disgust sensitivity as an olfactory marker of general disgust sensitivity vital to the protection against environmental hazards in people whose sensory defense system has been compromised by either visual or auditory loss. Moreover, some of the previously mentioned research had insufficient numbers of participants (Cox et al., 2002;Cuevas et al., 2010;Dormal, Crollen, Baumans, Lepore, & Collignon, 2016;Jiang, Stecker, Boynton, & Fine, 2016;Petitto et al., 2000), making the conclusions weak and thus likely to produce a type II error of false-negative conclusions. ...
... Notably, our study provides compelling evidence on the effects of sensory loss on body odor disgust sensitivity due to the sample sizeto date, studies including deaf and blind participants were largely underpowered (eight participants in Cuevas et al. 2010; seven individuals in Jiang et al. 2016; ten blind people in Dormal et al. 2016;11 deaf people in Petitto et al., 2000; or two deaf participants in Cox et al., 2002). ...
Article
Disgust might be elicited by various sensory channels, including the sense of smell. It has been previously demonstrated that unpleasant odors emitted by an external source are more disgusting than those emitted by oneself (the source effect). As disgust’s main purpose is to help organisms avoid potentially dangerous, contaminating objects, individuals with visual or hearing sensory impairment (thus, with an impeded ability to detect cues indicating pathogen threat) might have developed an increased levels of olfactory disgust sensitivity (modality compensation in disgust sensitivity). We set out to investigate disgust sensitivity in olfaction using the Body Odor Disgust Scale (BODS) on a large sample of 74 deaf and 98 blind participants, with comparison to control groups without sensory impairment (N = 199 in total). The results did not support the hypothesis of modality compensation in disgust sensitivity. Contrary to previous research, neither sex nor age influenced the outcomes. Evidence for the source effect was found. Acquired data are interpreted in the light of social desirability. The emphasis put on the olfaction by blind and deaf individuals is discussed.
... One study found superior performance on an n-back task with raised tactile letters but only at intermediate load levels (Bliss et al. 2004). Blind individuals also recall lists of consonants in serial order better than sighted participants, even when required to complete an intervening pitch discrimination task prior to recall (Dormal et al. 2016). Although pitch discrimination may not provide sufficient interference for a verbal memory task. ...
... Consistent with the current complex span task results, prior studies also find blindness-related verbal memory advantages persist amidst interference. As compared to sighted individuals, blind participants recall more letters and verbalizable sounds after completing an intervening pitch discrimination task (Dormal et al. 2016;). On a long-term memory task, blind participants recognized more verbalizable sounds than sighted participants after generating words beginning with a certain letter during the 8-9 min delay period (Cornell Kärnekull et al. 2016). ...
Article
Full-text available
Previous studies suggest that people who are congenitally blind outperform sighted people on some memory tasks. Whether blindness-associated memory advantages are specific to verbal materials or are also observed with nonverbal sounds has not been determined. Congenitally blind individuals (n = 20) and age and education matched blindfolded sighted controls (n = 22) performed a series of auditory memory tasks. These included: verbal forward and backward letter spans, a complex letter span with intervening equations, as well as two matched recognition tasks: one with verbal stimuli (i.e., letters) and one with nonverbal complex meaningless sounds. Replicating previously observed findings, blind participants outperformed sighted people on forward and backward letter span tasks. Blind participants also recalled more letters on the complex letter span task despite the interference of intervening equations. Critically, the same blind participants showed larger advantages on the verbal as compared to the nonverbal recognition task. These results suggest that blindness selectively enhances memory for verbal material. Possible explanations for blindness-related verbal memory advantages include blindness-induced memory practice and ‘visual’ cortex recruitment for verbal processing.
... Numerical skills and language In numerical cognition, the blind made fewer errors while solving certain basic arithmetic operations, e.g., 9x8 (Dormal, Crollen, et al. 2016) but were not found different from the sighted when solving problems requiring more calculations, e.g., 2 peaches cost 17 cents, how much would a dozen cost? (Rokem and Ahissar 2009). ...
... When measuring recalling span scores, the emerging picture is not very clear. On the one hand, simple digit-, word-and pseudo-word-span scores are mostly found to be higher in the blind (Rokem and Ahissar 2009;Crollen et al. 2011;in children Withagen et al. 2013;Dormal, Crollen, et al. 2016). On the other hand, when adding computational complexity, we find heterogeneous results. ...
Thesis
Blindness early in life leads to major changes in the functional architecture of the brain. The occipital lobes, no longer processing visual information, turn to processing auditory and tactile input and high-order cognitive functions such as language and memory. This functional reorganization offers a window into the influence of experience on brain development in humans. We studied the outcomes of this reorganization and its potential precursors. First, we used functional magnetic resonance imaging (fMRI) in order to delineate regions in the visual cortex according to their sensitivity to high-order cognitive functions. Then, using functional connectivity, we demonstrated distinct connections from those regions to the rest of the brain. Crucially, we found a functional correspondence between the visual regions and their connected brain networks. Then, using functional connectivity in neonates, we provided preliminary evidence in support of the proposition that innate connectivity biases underlie functional reorganization. Second, we focused on language, one of the reorganized functions in blindness, and used magnetoencephalography (MEG) to investigate verbal semantic processing. We found temporally equivalent but spatially different activation across the blind and the sighted. In the blind, the occipital cortex had a unique contribution to semantic category discrimination. However, the cerebral implementation of semantic categories was more variable in the blind than in the sighted. Our results advance the knowledge about brain.
... Studies have shown inconsistent results regarding WM ability in the intact senses of individuals with blindness or deafness. In relation to blindness and the auditory modality, some indicate better (Dormal et al., 2016;Heled and Oshri, 2021;Pigeon and Marin-Lamellet, 2015;Withagen et al., 2013) and others equal performance compared to controls (Park et al., 2011;Rokem and Ahissar, 2009;Vecchi et al., 2004). However, tactile WM has been shown to be superior and equal to controls (Cohen et al., 2010;Heled and Oshri, 2021;Occelli et al., 2017;Vecchi et al., 2004), but also worse (Aleman et al., 2001;Cornoldi et al., 1991;Vecchi, 1998;Vecchi et al., 2004). ...
... Our findings are in accordance with previous reports of superior WM abilities in individuals with blindness, as compared to controls in the auditory (Beauvais et al., 2004;Bliss et al., 2004;Dormal et al., 2016;Withagen et al., 2013) as well as tactile modalities (Cohen et al., 2011;Papagno et al., 2017). This indicates that lack of sensory ability may improve WM performance in the intact senses, presumably as a result of extended use of those senses (Bolognini et al., 2010;Cohen et al., 2010). ...
Article
Full-text available
The sensory compensation hypothesis posits that sensory deficits in one modality can lead to enhanced performance of cognitive tasks relying on another, intact modality. Most studies in this area have explored the visual and auditory senses, with inconsistent findings. Meanwhile, the tactile modality has rarely been examined in this context. The present study compared working memory (WM) abilities in the intact senses of individuals with sensory deprivation. Fourteen participants with blindness and 20 with deafness performed a tactile WM task and a verbal or visuospatial WM tasks, respectively. They were compared to 22 age- and education-matched controls who performed all WM tasks. Results showed participants with blindness outperform the other two groups in the tactile WM task and are better than controls in the auditory task. The deafness group outperformed the controls in the visuospatial but not the tactile task. The forward span was longer than the backward span in all modality types and no group by modality interaction was found. Finally, the effect size of differences between blindness and control groups were significantly higher than those of the deafness and control groups' differences. These findings show that blindness and deafness are associated with WM superiority in the intact modality, although not equally. Therefore, the sensory compensation hypothesis in the context of WM is only partially supported as factors, other than deprivation per se may influence performance.
... late-onset deafness on emotion recognition. Indeed, whereas the effects of onset of the sensory deprivation on brain/behavior reorganization have been extensively studied in case of blindness (e.g., Bedny et al., 2010Bedny et al., , 2012Cattaneo et al., 2007;Collignon et al., 2013;Dormal et al., 2016;Voss et al., 2004Voss et al., , 2008; for reviews see Cattaneo et al., 2008;Maurer et al., 2005), effects related to age at onset of deafness have only been so far marginally considered, and mainly in the context of cochlear implant use (Fengler et al., 2017;Gallego et al., 2016). At the neural level, an early study (Sadato et al., 2004) showed that recruitment of the auditory cortex during visual processing was larger in early than in late deaf individuals; furthermore, animals models report that crossmodal activation of primary auditory cortex differs depending on deafness onset (e.g., Chabot et al., 2015). ...
Article
Deaf individuals may compensate for the lack of the auditory input by showing enhanced capacities in certain visual tasks. Here we assessed whether this also applies to recognition of emotions expressed by bodily and facial cues. In Experiment 1, we compared deaf participants and hearing controls in a task measuring recognition of the six basic emotions expressed by actors in a series of video-clips in which either the face, the body, or both the face and body were visible. In Experiment 2, we measured the weight of body and face cues in conveying emotional information when intense genuine emotions are expressed, a situation in which face expressions alone may have ambiguous valence. We found that deaf individuals were better at identifying disgust and fear from body cues (Experiment 1) and in integrating face and body cues in case of intense negative genuine emotions (Experiment 2). Our findings support the capacity of deaf individuals to compensate for the lack of the auditory input enhancing perceptual and attentional capacities in the spared modalities, showing that this capacity extends to the affective domain.
... In general, the behavioral literature of executive functions in blind subjects is very heterogeneous. Several studies show an executive advantage in blind subjects (e.g., Crollen et al. 2011;Withagen et al. 2013 in blind children; Dormal et al. 2016) while others find no differences between blind and sighted subjects (Bliss et al. 2004;Wan et al. 2010;Pigeon and Marin-Lamellet 2015). Executive abilities in the blind were also shown to depend on task complexity and perceptual stimulus parameters (Rokem and Ahissar 2009;Occelli et al. 2017). ...
Article
In early blind individuals, brain activation by a variety of nonperceptual cognitive tasks extends to the visual cortex, while in the sighted it is restricted to supramodal association areas. We hypothesized that such activation results from the integration of different sectors of the visual cortex into typical task-dependent networks. We tested this hypothesis with fMRI in blind and sighted subjects using tasks assessing speech comprehension, incidental long-term memory and both verbal and nonverbal executive control, in addition to collecting resting-state data. All tasks activated the visual cortex in blind relative to sighted subjects, which enabled its segmentation according to task sensitivity. We then assessed the unique brain-scale functional connectivity of the segmented areas during resting state. Language-related seeds were preferentially connected to frontal and temporal language areas; the seed derived from the executive task was connected to the right dorsal frontoparietal executive network; and the memory-related seed was uniquely connected to mesial frontoparietal areas involved in episodic memory retrieval. Thus, using a broad set of language, executive, and memory tasks in the same subjects, combined with resting state connectivity, we demonstrate the selective integration of different patches of the visual cortex into brain-scale networks with distinct localization, lateralization, and functional roles.
... Congenitally blind people with no light perception are a rare group that can be extraordinarily difficult to find and recruit for scientific research. In comparison with previous studies, our sample can even be considered large (see for instance, 8 early-blind people in Cuevas et al. 2010;7 early-blind individuals in Jiang et al. 2016; 10 early-blind people in Dormal et al. 2016). Nevertheless, further studies addressing the issue of tallness stereotypes should take that into account and focus on obtaining larger samples of participants. ...
Article
Full-text available
The stereotype of a tall man has been reported in numerous studies. High stature is commonly associated with advantages such as leadership skills, wealth, intelligence or social status, and actual differences between the short and the tall men were indeed found for these traits, mainly in favor of the tall men. It is not certain, however, whether the height-related effects are biologically determined or if they result from socially-driven mechanisms. In this study we wanted to explore whether congenitally blind individuals, who are unable to perceive other people’s stature through the most salient, visual channel, share the positive, height-related stereotype. Thirty-four congenitally blind and forty-three sighted men and women rated four positive characteristics of a tall or a short man. It was found that none of the traits assigned to the tall man by the sighted people was assigned to this person by the blind individuals. In the congenitally blind group, no differences between the assessments of the tall and the short man were revealed. We discuss our findings in the context of social perception and stereotypes research.
... Recent studies (Sgaramella, Nota, Carrieri, Soresi, & Sato, 2017) would support this by suggesting that problem solving may play a key role in adapting to the difficulties confronting elderly people with VI when performing routine activities. It was also recently shown (Dormal, Crollen, Baumans, Lepore, & Collignon, 2016) that vision is not required for effective working memory, and that persons with VI rely on non-visual cognitive strategies such as verbal description. In addition to good mental capacity, coping in everyday life and maintaining a good QoL despite VI may also depend on stable general health, resilience, or a supportive spouse. ...
Article
Aim was to explore the health-related quality of life (HRQoL) and related factors among older adults with visual impairment (VI). A total of 39 independently living subjects aged ⩾65 years (83 ± 6.5), referred to the Low Vision Center of the Oulu University Hospital, Finland during one year participated in the study. The participants had low vision or blindness as defined by the World Health Organization (WHO). The 15D, a generic HRQoL instrument, was used to assess the HRQoL, and an ophthalmic examination was performed to assess vision. A population-based control group (n = 1074) was available for comparison. The mean 15D index scores for the participants and the control group were 0.768 (SD = 0.089) and 0.827 (SD = 0.044), respectively, (p < .002). In the dimensions of move (p < .05), see (p < .001), breath (p < .05), usual activities (p < .001), depression (p < .05), and distress (p < .05), the study participants scored statistically significantly lower than the control group. However, the participants had better mental function scores (0.856 vs 0.773, p < .05). Among the participants, there was no difference in the 15D by gender (men 0.755, women 0.774, p > .05), habitation (alone 0.768, with someone 0.770, p > .05), or age (r = –.084), nor did the extent of low vision appear to affect the 15D index in this material. The older adults with VI had poorer 15D index score than Finnish population of equal age, but they scored better in the dimension of mental function. Mental skills may indeed be crucial for independent living despite VI.
... http://dx.doi.org/10.1101/390450 doi: bioRxiv preprint first posted online Aug. 13, 2018; (Amedi et al., 2003;Collignon, Renier, Bruyer, Tranduy, & Veraart, 2006;Dormal, Crollen, Baumans, Lepore, & Collignon, 2016;Hull & Mason, 1995;Roder, Rösler, & Neville, 2001;Rokem & Ahissar, 2009;Swanson & Luxenberg, 2009;Tillman & Bashaw, 1968;Withagen, Kappers, Vervloed, Knoors, & Verhoeven, 2013). Whether "visual" cortex are functionally relevant to executive processes and whether this functional relevance underlies previously observed behavioral advantages remains to be tested in future research. ...
Preprint
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How functionally flexible is human cortex? In congenitally blind individuals, visual cortices are active during auditory and tactile tasks. The cognitive role of these responses and the underlying mechanisms remain uncertain. A dominant view is that, in blindness, visual cortices process information from low-level auditory and somatosensory systems. An alternative hypothesis is that higher-cognitive fronto-parietal systems take over visual cortices. We report that, in congenitally blind individuals, right-lateralized visual cortex responds to executive-load in a go/no-go task. These right-lateralized occipital cortices of blind, but not sighted, individuals mirrored the executive-function pattern observed in fronto-parietal systems. In blindness, the same visual cortex area, at rest, also increases its synchronization with prefrontal executive control regions and decreases its synchronization with auditory and sensorimotor cortices. These results support the hypothesis of top-down fronto-parietal takeover of visual cortices, and suggest that human cortex is highly flexible at birth.
... Several studies show an executive advantage in blind subjects (e.g. Crollen et al. 2011;Withagen et al. 2013 in blind children; Dormal et al. 2016) while others find no differences between blind and sighted subjects (e.g. Bliss et al. 2004;Wan et al. 2010;Pigeon and Marin-Lamellet 2015). ...
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In early blind individuals, brain activation by a variety of non-perceptual cognitive tasks extends to the visual cortex, while in the sighted it is restricted to supramodal association areas. We hypothesized that such activation results from the integration of different sectors of the visual cortex into typical task-dependent networks. We tested this hypothesis with fMRI in blind and sighted subjects using tasks assessing speech comprehension, incidental long-term memory and both verbal and non-verbal executive control, in addition to collecting resting-state data. All tasks activated the visual cortex in blind relative to sighted subjects, which enabled its segmentation according to task sensitivity. We then assessed the unique brain-scale functional connectivity of the segmented areas during resting state. Language-related seeds were preferentially connected to frontal and temporal language areas; the seed derived from the executive task was connected to the right dorsal frontoparietal executive network; the memory-related seed was uniquely connected to mesial frontoparietal areas involved in episodic memory retrieval. Thus, using a broad set of language, executive, and memory tasks in the same subjects, combined with resting state connectivity, we demonstrate the selective integration of different patches of the visual cortex into brain-scale networks with distinct localization, lateralization, and functional roles.
... In addition, [13] stated that dyscalculia may lie in disturbances of domain-general cognitive mechanisms such as working memory, visual-spatial processing, or attention. Working memory plays a significant role in encouraging mastery of arithmetic in adolescents, and both cases are closely linked to meetings where working memory is a cognitive component of promoting arithmetic skills [28], [29]. [25] suggested that individuals with both working memory disorders and math deficits may be best identified as suffering from secondary developmental dyscalculia. ...
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Dyscalculia is one of the less well-known learning problems in mathematics due to lack of exposure and study. Children with dyscalculia usually face arithmetic and symbolic number comparison issues, with about 3-6 percent of individuals affected. The lack of wide-ranging study and inconsistency in the condition's characterizations through studies have impeded progress in identifying the root causes of dyscalculia and how best to handle it. This problem can be more serious because it can prolong up to adulthood. Therefore, this paper will discuss the general aspects related to dyscalculia problems and their effects on children in their lives. This paper also explains the signs and symptoms that are needed to understand children who may have dyscalculia. Finally, this paper discusses what treatments or methods can be used significantly to help children improve their mastery and mathematical skills, including treatment for co-occurring issues. The implications are society should be aware of possible problems with their children related to dyscalculia and should always increase their initiative to use various methods to address the symptoms of dyscalculia, especially for children who also have other learning problems such as dyslexia and ADHD. Besides, increased knowledge of this distinction going forward, combined with longitudinal observational studies, provides tremendous potential to deepen our understanding of the condition and establish successful educational approaches.
... Interestingly, the presence of these compensatory mechanisms appears to be strongly dependant on the onset time of visual deprivation (Bavelier and Neville 2002;Voss et al. 2013). Contrary to congenital blindness or blindness acquired during the first few years of life (i.e., early blindness), late-onset blindness typically gives rise to lower behavioral compensatory mechanisms (Dormal et al. 2016; for a review, see Voss et al. 2013). ...
Article
Although often considered a non-dominant sense for spatial perception, chemosensory perception can be used to localize the source of an event and potentially help us navigate through our environment. Would blind people who lack the dominant spatial sense -vision- develop enhanced spatial chemosensation or, alternatively, suffer from the lack of visual calibration on spatial chemosensory perception? To investigate this question, we tested odorant localization abilities across nostrils in blind people compared to sighted controls, and if the time of vision loss onset modulates those abilities. We observed that congenitally blind individuals (10 subjects) outperformed sighted (20 subjects) and late-blind subjects (10 subjects) in a birhinal localization task using mixed olfactory-trigeminal stimuli. This advantage in congenitally blind people was selective to olfactory localization but not observed for odorant detection or identification. We therefore showed that congenital blindness but not blindness acquired late in life is linked to enhanced localization of chemosensory stimuli across nostrils, most probably of the trigeminal component. In addition to previous studies highlighting enhanced localization abilities in auditory and tactile modalities, our current results extend such enhanced abilities to chemosensory localization.
... Hal ini disebabkan oleh perolehan informasi dan pemahaman bahasa lebih sedikit bila dibandingkan dengan siswa normal. Mereka pada umumnya mendapatkan informasi dari indera yang masih berfungsi, seperti indera penglihatan, perabaan, pengecapan, dan penciuman (Dormal, Crollen, Baumans, Lepore, Collignon, 2016). ...
... Over the past decades, a large set of studies on numerical performances following early visual deprivation have shown that blind people are able to overcome their lack of vision and develop various numerical skills. Congenitally blind individuals were indeed found to perform as good (or even better) as their sighted peers in number comparison and parity judgement tasks (Castronovo & Seron, 2007), counting (Crollen et al., 2014), estimation tasks (Castronovo & Delvenne, 2013;Ferrand, Riggs, & Castronovo, 2010;Togoli, Crollen, Arrighi, & Collignon, 2020) and even in arithmetic (Crollen, Warusfel, Noël, & Collignon, 2021;Dormal, Crollen, Baumans, Lepore, & Collignon, 2016). In some numerical and even spatial memory tasks (Crollen et al., 2021), the blind's scores in the tactile modality were equivalent to the ones of the sighted performing the same task in the visual modality. ...
Article
Geometry intuitions seem to be rooted in a non-verbal system that humans possess since early age. However, the mechanisms underlying the comprehension of basic geometric concepts remain elusive. Some authors have suggested that the starting point of geometry development could be found in the visual perception of specific features in our environment, thus conferring to vision a foundational role in the acquisition of geometric skills. To examine this assumption, a test probing intuitive understanding of basic geometric concepts was presented to congenitally blind children and adults. Participants had to detect the intruder among four different shapes, from which three instantiated a specific geometrical concept and one (the intruder) violated it. Although they performed above the chance level, the blind presented poorer performance than the sighted participants who did the task in the visual modality (i.e., with the eyes open), but performed equally well than the sighted who did the task in the tactile modality (i.e., with a blindfold). We therefore provide evidence that geometric abilities are impacted by the lack of vision.
... The finding that visually impaired participants performed as well or better than sighted controls in both storage and manipulation functions is consistent with previous studies (Cohen et al., 2010;Dormal et al., 2016;Occelli et al., 2017;Papagno et al., 2017;Rokem & Ahissar, 2009;Vecchi, 1998;Vecchi et al., 1995;Withagen et al., 2013). This difference has been explained under the premise that WM capacity, which is presumably relatively similar across modalities at birth, grows with practice (Cohen et al., 2010). ...
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Neuropsychological assessment tools for individuals with blindness are relatively scarce. In the current study, we assessed the validity of the Tactual Span, a task aimed at evaluating tactile working memory. During the task, the fingers of both hands are touched in specific sequences of ascending difficulty, which participants are asked to repeat in exact and reverse order. Twelve participants with congenital blindness and 13 with acquired blindness were examined alongside 18 sighted controls, matched to the experimental group with respect to age and education. Participants performed the Tactual Span and three additional tasks assessing working memory in the auditory modality, as well as a Semantic Fluency test. Results showed that the Tactual Span was significantly correlated with most of the other working memory measures, in all groups, but not with the Semantic Fluency test. In addition, the congenital and acquired blindness groups performed similarly to one another and better than sighted controls on most working memory tasks, but not on the Semantic Fluency test. Findings suggest that the Tactual Span is a feasible task for measuring tactile working memory in individuals with congenital and acquired blindness. Therefore, it can expand the cognitive assessment toolbox of professionals working with blind individuals and increase the strength of conclusions drawn from cognitive assessments in educational and vocational settings.
... Matematika selain sebagai salah satu disiplin ilmu dalam dunia pendidikan juga merupakan salah satu bidang studi yang sangat penting, baik bagi peserta didik maupun bagi pengembangan bidang keilmuan yang lain . Kedudukan matematika dalam dunia pendidikan sangat besar manfaatnya karena matematika adalah alat dalam pendidikan kecerdasan akal dan memiliki pengaruh yang signifikan terhadap pengembangan ilmu pengetahuan dan teknologi (Dormal et al., 2016) Masalah Melalui penerapan pendekaan Reciprocal teaching dalam pembelajaran matematika, tujuan penelitian ini antara lain; 1) meningkatkan hasl belajar matematika siswa; 2) meningkatkan kemampuan guru dalam mengelola pembelajaran; dan 3) mengetahui respon siswa dalam mengikuti pembelajaran matematika ketika menerapkan pedekatan reciprocal teaching. ...
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Penelitian ini merupakan Penelitian Tindakan Kelas (PTK) yang bertujuan untuk meningkatkan hasil belajar matematika siswa pada materi operasi vektor melaui pendekatan reciprocal teaching. Subyek dalam penelitian ini yaitu peserta didik Kelas X IPA SMA Santa Angela Atambua yang berjumlah 12 orang. Dalam mengumpulkan data, peniliti menggunakan beberapa instrumen, antara lain: lembar observasi kemampuan guru mengelola pembelajaran; lembar penilaian respons peserta didik, dan tes. Penelitian ini dilakukan dalam dua siklus. Hasil analisis data pada siklus 1, menunjukkan bahwa secara umum terdapat peningkatan hasil belajar siswa walaupun peningkatan tersebut dalam kategori rendah (nilai N-gain = 0,283); Kemampuan guru mengelola pembelajaran dalam kategori cukup baik; dan respon peserta didik dalam kategori kurang baik. Hasil analisis data pada siklus 2, menunjukkan adannya peningkatan penguasaan akan konsep matematik dan peningkatan tersebut dalam ketegori sedang (nilai N-gain: 0,584); Kemampuan guru dalam mengelola pembelajaran dalam kategori baik dan respon peserta didik dalam kategori baik. Dengan demikian, kami menyimpulkan bahwa pendekatan reciprocal teaching dapat meningkatkan hasil belajar matematik siswa khususnya pada materi operasi vektor, meningkatkan kemampuan guru dalam mengelola pembelajaran dan juga dapat meningkatkan keaktifan siswa dalam pembelajaran matematika khususnya pada materi operasi vektor.
... Research on deductive reasoning and working memory in people who are blind does not clearly support either of these [13][14][15]. For instance, in terms of working memory tested via the auditory modality, certain studies indicate better performance by people who are blind [16][17][18][19], while others find they perform equally well compared to sighted controls [20][21][22]. Working memory can also be tested via the tactile modality, and here too there exist inconsistencies in the literature, as certain studies show superior or equal performance by people with blindness compared to sighted controls [17,[22][23][24], while others show deficiencies [22,[25][26][27]. ...
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Deductive reasoning and working memory are integral parts of executive functioning and are important skills for blind people in everyday life. Despite the importance of these skills, the influence of visual experience on reasoning and working memory skills, as well as on the relationship between these, is unknown. In this study, fifteen participants with congenital blindness (CB), fifteen with late blindness (LB), fifteen sighted blindfolded controls (SbfC), and fifteen sighted participants performed two tasks of deductive reasoning and two of working memory. We found that while the CB and LB participants did not differ in their deductive reasoning abilities, the CB group performed worse than the sighted controls, and the LB group performed better than the SbfC group. Those with CB outperformed all the other groups in both of the working memory tests. Working memory is associated with deductive reasoning in all three visually impaired groups, but not in the sighted group. These findings suggest that deductive reasoning is not a uniform skill, and that it is associated with visual impairment onset, the level of reasoning difficulty, and the degree of working memory load.
... Another (not mutually exclusive) source of variability could be individual adaptations to blindness, such as the compensatory use of other senses (Röder et al., 1999;Van Boven et al., 2000;Goldreich and Kanics, 2003;Collignon et al., 2009;Beaulieu-Lefebvre et al., 2011) and cognitive faculties (e.g., increased reliance and improved memory and verbal skills; Tillman and Bashaw, 1968;Pozar, 1982;Raz et al., 2007;Occelli et al., 2016;Dormal et al., 2016;Loiotile et al., 2019). Plasticity correlated to these different abilities has been found in the visual cortex of the blind (Amedi et al., 2003;Gougoux et al., 2005), and differential abilities and reliance on these modes of compensation (e.g., reading Braille books as opposed to listening to audiobooks) across individuals could lead to variability in visual system connectivity, as well as differential functional responses (van den Hurk et al., 2017;Rosenke et al., 2020;Mattioni et al., 2020b). ...
Article
Visual cortex organization is highly consistent across individuals. But to what degree does this consistency depend on life experience, in particular sensory experience? In this study, we asked whether visual cortex reorganization in congenital blindness results in connectivity patterns that are particularly variable across individuals, focusing on resting-state functional connectivity (RSFC) patterns from the primary visual cortex. We show that the absence of shared visual experience results in more variable RSFC patterns across blind individuals than sighted controls. Increased variability is specifically found in areas that show a group difference between the blind and sighted in their RSFC. These findings reveal a relationship between brain plasticity and individual variability; reorganization manifests variably across individuals. We further investigated the different patterns of reorganization in the blind, showing that the connectivity to frontal regions, proposed to have a role in the reorganization of the visual cortex of the blind toward higher cognitive roles, is highly variable. Further, we link some of the variability in visual-to-frontal connectivity to another environmental factor-duration of formal education. Together, these findings show a role of postnatal sensory and socioeconomic experience in imposing consistency on brain organization. By revealing the idiosyncratic nature of neural reorganization, these findings highlight the importance of considering individual differences in fitting sensory aids and restoration approaches for vision loss.
... The research by Dormal, Crollen, Baumans, Lepore, and Collignon (2016) suggests at least that our audacious hypothesis is not completely unrealistic. Indeed, the research by Dormal et al. allows to compare the three groups of individuals (EB, LB, and SC) on two types of addition and subtraction problems. ...
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The question of teaching a standard written algorithm for the four arithmetical operations in the first years of elementary school is increasingly raised as a consequence of the possibility of using calculators, tablets, and computers. This article first presents arguments both against and for maintaining this teaching in the first school years. Then, it presents an analysis of the procedure—whether it implies the standard algorithm or not—used by second grade students to solve a subtraction verbal problem. The 4720 students involved in the research were divided in a control group (n = 2101) and an experimental group (n = 2619) in which the standard written algorithm (SWA) was taught, or not taught, respectively. The effectiveness of algorithm use was analyzed not only in terms of accuracy of the answers, but also for its influence on the choice of the correct arithmetical operation and for its choice by the students as a function of their ability. The SWA was strongly associated with the use of the false arithmetical operation (effect size ϕ = 0.79)—addition instead of subtraction—but was chosen by students of all levels of ability. The latter result suggests that the SWA is well suited for the most advanced students but far less for the others who use it mechanically and without reflection.
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Finger counting can be useful in solving arithmetic problems, noticeably because it reduces the working memory demand of mental calculations. However, proprioceptive information might not be sufficient to keep track of the number of fingers raised during problem solving, and visual input may play an important role in this process. The present study was designed to address this question and shows that 8-year-old children look at their fingers in 60% of the trials during finger counting when solving additive problems. Moreover, our results reveal that the frequency of finger looking is negatively correlated with working memory capacities and is higher for more difficult problems. These findings suggest that finger looking is recruited in managing the cognitive demand of the arithmetic task, probably by providing additional external cues to monitor the number of steps that have to be incremented during finger counting.
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Cognitive functioning is based on sensory information. Both sensory deprivation and ageing cause cognitive deterioration. The aim of this study was to evaluate the effects of these two factors upon one another. The present study was cross sectional, comparing 137 blind and 124 normal vision participants using the Weschler memory scale (WMS-III), the mini mental state examination (MMSE) and the verbal fluency task (VFT). These scales measure cognitive abilities such as attention and calculation, auditory memory, working memory, associative learning, orientation, registration, attention, recall, language and phonemic and semantic verbal fluency. Findings indicated that normal vision participants performed significantly better in cognitive tasks compared to blind individuals. Both groups showed a similar pattern of decline in scores of cognitive ability with increase in age. Results suggested that sensory deprivation alone may not be considered as a detrimental factor in cognitive degeneration over the life span.
Book
Written for pre-service and in-service educators, as well as parents of children in preschool through grade five, this book connects research in cognitive development and math education to offer an accessibly written and practical introduction to the science of elementary math learning. Structured according to children's mathematical development, How Children Learn Math systematically reviews and synthesizes the latest developmental research on mathematical cognition into accessible sections that explain both the scientific evidence available and its practical classroom application. Written by an author team with decades of collective experience in cognitive learning research, clinical learning evaluations, and classroom experience working with both teachers and children, this amply illustrated text offers a powerful resource for understanding children's mathematical development, from quantitative intuition to word problems, and helps readers understand and identify math learning difficulties that may emerge in later grades. Aimed at pre-service and in-service teachers and educators with little background in cognitive development, the book distills important findings in cognitive development into clear, accessible language and practical suggestions. The book therefore serves as an ideal text for pre-service early childhood, elementary, and special education teachers, as well as early career researchers, or as a professional development resource for in-service teachers, supervisors and administrators, school psychologists, homeschool parents, and other educators.
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When people lose a sense there is thought to be an increase in the remaining sensory functions. The case of vision has been of interest due to the prevalence of visual impairment worldwide, and the question of whether blind persons’ evidence an increased acuteness in other senses has been a subject of controversy for over a century. In sensory analysis, the use of visually impaired panellists (VIP) is not a common practice and the differences and similarities between VIP and sighted panellists (SP) have not been widely studied. The objective of this research was to understand the differences between panels in terms of discrimination and descriptive task, as well as memory: short-term and long-term semantic and sensory memory. Two panels were trained to evaluate dry and fresh chilies. One panel consisted of VIP and the other of SP. Results showed no differences in discrimination tasks (3 triangular tests). In descriptive tests, although results of mean scores by product* attribute have similar results between panels, VIP had a greater discrimination ability for dry and fresh chilies (P < 0.05 in ANOVA by descriptors). Differences in repeatability were also observed (P <0.05) in the session factor of the ANOVA. When comparing short-term and long-term sensory memory, no significant difference was found between panellists. However, when measuring semantic memory, the VIP was able to recall more information: 39.6% of the sensory descriptors used in the training after six months. SP was able to recall 21% (P <0.043). Overall, results showed that mean scores of a sensory profiling will be similar using VIP or SP, but there exist differences linked to semantic memory that can be responsible for a better panel performance. These results encourage the use of VIP as being both similar to SP in sensory discrimination, but more importantly, for being socially responsible.
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Although many users adopt voice-enabled technology today, there is lack of understanding on voice technology designs suitable for older adults with visual impairments. This study aims at investigating the auditory information processing capability of older adults with visual impairments and their preferences for voice user interfaces and interactions. A convenience sampling method recruited 20 older adults with visual impairments. The auditory information processing capability was measured with a word memory span task, and the Wizard-of-Oz method helped to explore user requirements for voice technology. The word memory span was 3.00 ± 0.34, which leads to the recommendation that information architectures include no greater than three layers of horizontal or vertical menu structures. The majority of the participants (75%) preferred the combination of inbound and outbound calls to interact with the system, and 65% appreciated the interactive, structured navigation menu user interfaces that empower the user to control the system. The study contributes to user-friendly voice technology for older adults with visual impairments.
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The phenomenology of the blind has provided an age-old, unparalleled means of exploring the enigmatic link between the brain and mind. This paper delves into the unique phenomenological experience of a man who became blind in adulthood. He subsequently underwent both an Argus II retinal prosthesis implant and training, and extensive training on the EyeMusic visual to auditory sensory substitution device, thereby becoming the first reported case to date of dual proficiency with both devices. He offers a firsthand account into what he considers the great potential of combining sensory substitution devices with visual prostheses as part of a complete visual restoration protocol. While the Argus II retinal prosthesis alone provided him with immediate visual percepts by way of electrically stimulated phosphenes elicited by the device, the EyeMusic SSD requires extensive training from the onset. Yet following the extensive training program with the EyeMusic sensory substitution device, our subject reports that the sensory substitution device allowed him to experience a richer, more complex perceptual experience, that felt more "second nature" to him, while the Argus II prosthesis (which also requires training) did not allow him to achieve the same levels of automaticity and transparency. Following long-term use of the EyeMusic SSD, our subject reported that visual percepts representing mainly, but not limited to, colors portrayed by the EyeMusic SSD are elicited in association with auditory stimuli, indicating the acquisition of a high level of automaticity. Finally, the case study indicates an additive benefit to the combination of both devices on the user's subjective phenomenological visual experience.
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Is vision a necessary building block for the foundations of mathematical cognition? A straightforward model to test the causal role visual experience plays in the development of numerical abilities is to study people born without sight. In this review we will demonstrate that congenitally blind people can develop numerical abilities that equal or even surpass those of sighted individuals; despite representing numbers using a qualitatively different representational format. We will also show that numerical thinking in blind people maps onto regions typically involved in visuo-spatial processing in the sighted, highlighting how intrinsic computational biases may constrain the reorganization of numerical networks in case of early visual deprivation. More generally, we will illustrate how the study of arithmetic abilities in congenitally blind people represents a compelling model to understand how sensory experience scaffolds the development of higher-level cognitive representations.
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BACKGROUND: Although a number of research studies on sensor technology for smart home environments have been conducted, there is still lack of consideration of human factors in implementing sensor technology in the home of older adults with visual disabilities. OBJECTIVE: This paper aims to advance knowledge of how sensor technology (e.g., Microsoft Kinect) should be implemented in the home of those with visual disabilities. METHODS: A convenience sample of 20 older adults with visual disabilities allowed us to observe their home environments and interview about the activities of daily living, which were analyzed via the inductive content analysis. RESULTS: Sensor technology should be integrated in the living environments of those with visual disabilities by considering various contexts, including people, tasks, tools, and environments (i.e., level-1 categories), which were further broken down into 22 level-2 categories and 28 level-3 categories. Each sub-category included adequate guidelines, which were also sorted by sensor location, sensor type, and data analysis. CONCLUSIONS: The guidelines will be helpful for researchers and professionals in implementing sensor technology in the home of older adults with visual disabilities.
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Studies of occipital cortex plasticity in blindness provide insight into how intrinsic constraints interact with experience to determine cortical specialization. We tested the cognitive nature and anatomical origins of occipital responses during non-verbal, non-spatial auditory tasks. In a go/no-go task, congenitally blind (N=23) and sighted (N=24) individuals heard rapidly occurring (<1/sec) non-verbal sounds and made one of two button presses (frequent-go 50%, infrequent-go 25%) or withheld a response (no-go, 25%). Rapid and frequent button presses heighten response selection/inhibition demands on the no-go trials: In sighted and blind adults a right-lateralized prefrontal (PFC) network responded most to no-go trials, followed by infrequent-go and finally frequent-go trials. In the blind group only, a right-lateralized occipital network showed the same response profile and laterality of occipital and PFC responses was correlated across blind individuals. A second experiment with spoken sentences and equations (N=16) found that no-go sensitive occipital network is distinct from previously identified occipital responses to spoken language. Finally, in resting-state data (N=30 blind, N=31 blindfolded sighted), no-go responsive 'visual' cortex of blind relative to sighted participants was more synchronized with PFC and less synchronized with primary auditory and sensory-motor cortices. No-go responsive occipital cortex showed higher synchrony with no-go responsive PFC than language responsive inferior frontal cortex. We conclude that in blindness, a right-lateralized occipital network responds to non-verbal executive processes, including response selection. These results suggest that connectivity with fronto-parietal executive networks is a key mechanism for plasticity in blindness.
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Sex differences favoring women have been found in a number of studies of episodic memory. This study examined sex differences in verbal, nonverbal, and visuospatial episodic memory tasks. Results showed that although women performed at a higher level on a composite verbal and nonverbal episodic memory score, men performed at a higher level on a composite score of episodic memory tasks requiring visuospatial processing. Thus, men can use their superior visuospatial abilities to excel in highly visuospatial episodic memory tasks, whereas women seem to excel in episodic memory tasks in which a verbalization of the material is possible.
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Distinct preference for visual number symbols was recently discovered in the human right inferior temporal gyrus (rITG). It remains unclear how this preference emerges, what is the contribution of shape biases to its formation and whether visual processing underlies it. Here we use congenital blindness as a model for brain development without visual experience. During fMRI, we present blind subjects with shapes encoded using a novel visual-to-music sensory-substitution device (The EyeMusic). Greater activation is observed in the rITG when subjects process symbols as numbers compared with control tasks on the same symbols. Using resting-state fMRI in the blind and sighted, we further show that the areas with preference for numerals and letters exhibit distinct patterns of functional connectivity with quantity and language-processing areas, respectively. Our findings suggest that specificity in the ventral 'visual' stream can emerge independently of sensory modality and visual experience, under the influence of distinct connectivity patterns.
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Various prominent models on serial order coding in working memory (WM) build on the notion that serial order is achieved by binding the various items to-be-maintained to fixed position markers. Despite being relatively successful in accounting for empirical observations and some recent neuro-imaging support, these models were largely formulated on theoretical grounds and few specifications have been provided with respect to the cognitive and/or neural nature of these position markers. Here we outline a hypothesis on a novel candidate mechanism to substantiate the notion of serial position markers. Specifically, we propose that serial order WM is grounded in the spatial attention system: (I) The position markers that provide multi-item WM with a serial context should be understood as coordinates within an internal, spatially defined system; (II) internal spatial attention is involved in searching through the resulting serial order representation; and (III) retrieval corresponds to selection by spatial attention. We sketch the available empirical support and discuss how the hypothesis may provide a parsimonious framework from which to understand a broad range of observations across behavioral, neural and neuropsychological domains. Finally, we pinpoint what we believe are major questions for future research inspired by the hypothesis.
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Though a clear interaction between finger and number representations has been demonstrated, what drives the development of this intertwining remains unclear. Here we tested early blind, late blind and sighted control participants in two counting tasks, each performed under three different conditions: a resting condition, a condition requiring hands movements and a condition requiring feet movements. In the resting condition, every sighted and late blind spontaneously used their fingers, while the majority of early blind did not. Sighted controls and late blind were moreover selectively disrupted by the interfering hand condition, while the early blind who did not use the finger-counting strategy remained unaffected by the interference conditions. These results therefore demonstrate that visual experience plays an important role in implementing the sensori-motor habits that drive the development of finger-number interactions.
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Abstract There is ample evidence suggesting a bidirectional connection between bodily movements and cognitive processes, such as problem solving. Current research suggests that previous movements can influence the problem-solving process, but it is unclear what phase of this process is affected. Therefore, we investigated participants' gaze behaviour in the first phase of arithmetic problem solving with two groups (plus group, minus group) to explore a spatial bias toward the left or the right while perceiving a problem-solving task (the water-jar problem) after two different movements. That is for the plus group sorting marbles from two outer bowls into one in the middle; for the minus group marbles had to be sorted from the middle bowl to the outer ones. We showed a right shift of spatial bias for the plus and to the left for the minus group in the perception and problem task. Although movements affected gaze, the groups did not differ in their overall problem-solving strategies; however, the first correct solutions did differ. This study provides further evidence of sensorimotor effects on problem solving and spatial bias and offers insight into how a two-phase problem-solving process is guided by sensorimotor information.
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While the demonstration of crossmodal plasticity is well established in congenital and early blind individuals, great debate still surrounds whether those who acquire blindness later in life can also benefit from such compensatory changes. No proper consensus has been reached despite the fact that a proper understanding of the developmental time course of these changes, and whether their occurrence is limited to-or within-specific time windows, is crucial to our understanding of the crossmodal phenomena. An extensive review of the literature reveals that while the majority of investigations to date have examined the crossmodal plasticity available to late blind individuals in quantitative terms, recent findings rather suggest that this reorganization also likely changes qualitatively compared to what is observed in early blindness. This obviously could have significant repercussions not only for the training and rehabilitation of blind individuals, but for the development of appropriate neuroprostheses designed to aid and potentially restore vision. Important parallels will also be drawn with the current state of research on deafness, which is particularly relevant given in the development of successful neuroprostheses (e.g., cochlear implants) for providing auditory input to the central nervous system otherwise aurally deafferented. Lastly, this paper will address important inconsistencies across the literature concerning the definition of distinct blind groups based on the age of blindness onset, and propose several alternatives to using such a categorization.
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The ability to maintain the serial order of events is recognized as a major function of working memory. Although general models of working memory postulate a close link between working memory and attention, such a link has so far not been proposed specifically for serial-order working memory. The present study provided the first empirical demonstration of a direct link between serial order in verbal working memory and spatial selective attention. We show that the retrieval of later items of a sequence stored in working memory-compared with that of earlier items-produces covert attentional shifts toward the right. This observation suggests the conceptually surprising notion that serial-order working memory, even for nonspatially defined verbal items, draws on spatial attention.
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This article synthesizes published literature comparing the cognitive functioning of children who have math disabilities (MD) with that of (a) average-achieving children; (b) children who have reading disabilities (RD); and (c) children who have comorbid disabilities (MD+RD). Average achievers outperformed children with MD on measures of verbal problem solving, naming speed, verbal working memory (WM), visual-spatial WM, and long-term memory (LTM). Children with MD outperformed comorbid children on measures of literacy, visual-spatial problem solving, LTM, short-term memory (STM) for words, and verbal WM. Children with MD could be differentiated from children with RD only on naming speed and visual-spatial WM. Differences in cognitive functioning between children with MD and average achievers were related primarily to verbal WM when the effects of all other variables (e.g., age, IQ, and other domain categories) were partialed out.
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Recent evidence suggests that in representing numbers blind individuals might be affected differently by proprioceptive cues (e.g., hand positions, head turns) than are sighted individuals. In this study, we asked a group of early blind and sighted individuals to perform a numerical bisection task while executing hand movements in left or right peripersonal space and with either hand. We found that in bisecting ascending numerical intervals, the hemi-space in which the hand was moved (but not the moved hand itself) influenced the bisection bias similarly in both early blind and sighted participants. However, when numerical intervals were presented in descending order, the moved hand (and not the hemi-space in which it was moved) affected the bisection bias in all participants. Overall, our data show that the operation to be performed on the mental number line affects the activated spatial reference frame, regardless of participants' previous visual experience. In particular, both sighted and early blind individuals' representation of numerical magnitude is mainly rooted in world-centered coordinates when numerical information is given in canonical orientation (i.e., from small to large), whereas hand-centered coordinates become more relevant when the scanning of the mental number line proceeds in non-canonical direction. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Solving arithmetic problems has been shown to induce shifts of spatial attention in simple probe-detection tasks, subtractions orienting attention to the left side and additions to the right side of space. Whether these atten-tional shifts constitute epiphenomena or are critically linked to the calculation process is still unknown. In the present study, we investigate participants' performance on addition and subtraction solving while they have to detect central or lateralized targets. The results show that later-alized distractors presented in the hemifield congruent to the operation to be solved interfere with arithmetical solving: participants are slower to solve subtractions or additions when distractors are located on the left or on the right, respectively. These results converge with previous data to show that attentional shifts underlie not only number processing but also mental arithmetic. They extend them as they reveal the reverse effect of the one previously reported by showing that inducing attention shifts interferes with the solving of arithmetic problems. They also demonstrate that spatial attentional shifts are part of the calculation procedure of solving mentally arithmetic problems. Their functional role is to access, from the first operand, the representation of the result in a direction congruent to the operation.
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Although attentional processes and working memory seem to be significantly involved in the daily activities (particularly during navigating) of persons who are blind and who use these abilities to compensate for their lack of vision, few studies have investigated these mechanisms in this population. The aim of this study is to evaluate the selective, sustained and divided attention, attentional inhibition and switching and working memory of blind persons. Early blind, late blind and sighted participants completed neuropsychological tests that were designed or adapted to be achievable in the absence of vision. The results revealed that the early blind participants outperformed the sighted ones in selective, sustained and divided attention and working memory tests, and the late blind participants outperformed the sighted participants in selective, sustained and divided attention. However, no differences were found between the blind groups and the sighted group in the attentional inhibition and switching tests. Furthermore, no differences were found between the early and late blind participants in this set of tests. These results suggest that early and late blind persons can compensate for the lack of vision by an enhancement of the attentional and working memory capacities.
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We reviewed the literature on the role of working memory in the solution of arithmetic problems such as 3 + 4 or 345 + 29. The literature was neither comprehensive nor systematic, but a few conclusions are tenable. First, all three components of the working memory system proposed by Baddeley (i.e., central executive, phonological loop, and visual-spatial sketchpad) play a role in mental arithmetic, albeit under different conditions. Second, mental arithmetic requires central executive resources, even for single-digit problems. Third, further progress in understanding the role of working memory in arithmetic requires that researchers systematically manipulate factors such as presentation conditions (e.g., operand duration, format), problem complexity, task requirements (e.g., verification vs production), and response requirements (e.g., spoken vs written); and that they consider individual differences in solution procedures. Fourth, the encoding-complex model (Campbell, 1994) seems more likely to account for the variability observed in arithmetic solutions than other models of numerical processing. Finally, working memory researchers are urged to use mental arithmetic as a primary task because the results of the present review suggest that solution of problems that involve multiple digits are likely to involve an interaction of all the components of the working memory system.
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Recent behavioural and brain imaging studies have provided evidence for rightward and leftward attention shifts while solving addition and subtraction problems respectively, suggesting that mental arithmetic makes use of mechanisms akin to those underlying spatial attention. However, this hypothesis mainly relies on correlative data and the causal relevance of spatial attention for mental arithmetic remains unclear. In order to test whether the mechanisms underlying spatial attention are necessary to perform arithmetic operations, we compared the performance of right brain-lesioned patients, with and without left unilateral neglect, and healthy controls in addition and subtraction of two-digit numbers. We predicted that patients with left unilateral neglect would be selectively impaired in the subtraction task while being unimpaired in the addition task. The results showed that neglect patients made more errors than the two other groups to subtract large numbers, whereas they were still able to solve large addition problems matched for difficulty and magnitude of the answer. This finding demonstrates a causal relationship between the ability to attend the left side of space and the solving of large subtraction problems. A plausible account is that attention shifts help localizing the position of the answer on a spatial continuum while subtracting large numbers.
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Numerosity, the set size of a group of items, is processed by the association cortex, but certain aspects mirror the properties of primary senses. Sensory cortices contain topographic maps reflecting the structure of sensory organs. Are the cortical representation and processing of numerosity organized topographically, even though no sensory organ has a numerical structure? Using high-field functional magnetic resonance imaging (at a field strength of 7 teslas), we described neural populations tuned to small numerosities in the human parietal cortex. They are organized topographically, forming a numerosity map that is robust to changes in low-level stimulus features. The cortical surface area devoted to specific numerosities decreases with increasing numerosity, and the tuning width increases with preferred numerosity. These organizational properties extend topographic principles to the representation of higher-order abstract features in the association cortex.
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In numerical cognition vision has been assumed to play a predominant role in the elaboration of the numerical representations and skills. However, this view has been recently challenged by the discovery that people with early visual deprivation not only have a semantic numerical representation that shares the same spatial properties with that in sighted people, but also have better numerical estimation skills. Here, we show that blind people's superior numerical abilities can be found in different numerical contexts, whether they are familiar or more general. In particular, we found that blind participants demonstrated better numerical estimation abilities than sighted participants in both an ecologic footstep and an unfamiliar oral verbal production task. Blind participants also tend to show greater working memory skills compared to sighted participants. These findings support the notion that vision is not necessary in the development of numerical cognition and indicate that early visual deprivation may even lead to a general enhancement in numerical estimation abilities. Moreover, they further suggest that blind people's greater numerical skills might be accounted by enhanced high-level cognitive processes, such as working memory.
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Nine experiments of timed odd–even judgments examined how parity and number magnitude are accessed from Arabic and verbal numerals. With Arabic numerals, Ss used the rightmost digit to access a store of semantic number knowledge. Verbal numerals went through an additional stage of transcoding to base 10. Magnitude information was automatically accessed from Arabic numerals. Large numbers preferentially elicited a rightward response, and small numbers a leftward response. The Spatial–Numerical Association of Response Codes effect depended only on relative number magnitude and was weaker or absent with letters or verbal numerals. Direction did not vary with handedness or hemispheric dominance but was linked to the direction of writing, as it faded or even reversed in right-to-left writing Iranian Ss. The results supported a modular architecture for number processing, with distinct but interconnected Arabic, verbal, and magnitude representations. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
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Functional approaches to working memory (WM) have been proposed recently to better investigate "maintenance" and "processing" mechanisms. The cognitive load (CL) hypothesis presented in the "Time-Based Resource-Sharing" model (Barrouillet & Camos, 2007) suggests that forgetting from WM (maintenance) can be investigated by varying the presentation rate and processing speed (processing). In this study, young and elderly participants were compared on WM tasks in which the difference in processing speed was controlled by CL manipulations. Two main results were found. First, when time constraints (CL) were matched for the two groups, no aging effect was observed. Second, whereas a large variation in CL affected WM performance, a small CL manipulation had no effect on the elderly. This suggests that WM forgetting cannot be completely accounted for by the CL hypothesis. Rather, it highlights the need to explore restoration times in particular, and the nature of the refreshment mechanisms within maintenance.
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Working memory refers to a mental workspace, involved in controlling, regulating, and actively maintaining relevant information to accomplish complex cognitive tasks (e.g. mathematical processing). Despite the potential relevance of a relation between working memory and math for understanding developmental and individual differences in mathematical skills, the nature of this relationship is not well-understood. This paper reviews four approaches that address the relation of working memory and math: 1) dual task studies establishing the role of working memory during on-line math performance; 2) individual difference studies examining working memory in children with math difficulties; 3) studies of working memory as a predictor of mathematical outcomes; and 4) longitudinal studies of working memory and math. The goal of this review is to evaluate current information on the nature of the relationship between working memory and math provided by these four approaches, and to present some of the outstanding questions for future research.
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Numerosity estimation is phylogenetically ancient and foundational to human mathematical learning, but its computational bases remain controversial. Here we show that visual numerosity emerges as a statistical property of images in 'deep networks' that learn a hierarchical generative model of the sensory input. Emergent numerosity detectors had response profiles resembling those of monkey parietal neurons and supported numerosity estimation with the same behavioral signature shown by humans and animals.
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We investigated the role of vision in tactile enumeration within and outside the subitizing range. Congenitally blind and sighted (blindfolded) participants were asked to enumerate quickly and accurately the number of fingers stimulated. Both groups of participants enumerated one to three fingers quickly and accurately but were much slower and less accurate with four to nine fingers. Within the subitizing range, blind participants performed no differently from both sighted (blindfolded) and sighted-seeing participants. Outside of the subitizing range, blind and sighted-seeing participants showed better performance than did sighted-blindfolded participants, suggesting that lack of access to the predominant sensory modality does affect performance. Together, these findings further support the claim that subitizing is a general perceptual mechanism and demonstrate that vision is not necessary for the development of the subitizing mechanism.
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The notion that blindness leads to superior non-visual abilities has been postulated for centuries. Compared to sighted individuals, blind individuals show different patterns of brain activation when performing auditory tasks. To date, no study has controlled for musical experience, which is known to influence auditory skills. The present study tested 33 blind (11 congenital, 11 early-blind, 11 late-blind) participants and 33 matched sighted controls. We showed that the performance of blind participants was better than that of sighted participants on a range of auditory perception tasks, even when musical experience was controlled for. This advantage was observed only for individuals who became blind early in life, and was even more pronounced for individuals who were blind from birth. Years of blindness did not predict task performance. Here, we provide compelling evidence that superior auditory abilities in blind individuals are not explained by musical experience alone. These results have implications for the development of sensory substitution devices, particularly for late-blind individuals.
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This longitudinal study examined the relationship between working memory and individual differences in mathematics. Working memory measures, comprising the phonological loop, the visuospatial sketchpad, and the central executive, were administered at the start of first grade. Mathematics achievement was assessed 4 months later (at the middle of first grade) and 1 year later (at the start of second grade). Working memory was significantly related to mathematics achievement in both grades, showing that working memory clearly predicts later mathematics achievement. The central executive was a unique predictor of both first- and second-grade mathematics achievement. There were age-related differences with regard to the contribution of the slave systems to mathematics performance; the visuospatial sketchpad was a unique predictor of first-grade, but not second-grade, mathematics achievement, whereas the phonological loop emerged as a unique predictor of second-grade, but not first-grade, mathematics achievement.
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Congenitally blind individuals have been found to show superior performance in perceptual and memory tasks. In the present study, we asked whether superior stimulus encoding could account for performance in memory tasks. We characterized the performance of a group of congenitally blind individuals on a series of auditory, memory and executive cognitive tasks and compared their performance to that of sighted controls matched for age, education and musical training. As expected, we found superior verbal spans among congenitally blind individuals. Moreover, we found superior speech perception, measured by resilience to noise, and superior auditory frequency discrimination. However, when memory span was measured under conditions of equivalent speech perception, by adjusting the signal to noise ratio for each individual to the same level of perceptual difficulty (80% correct), the advantage in memory span was completely eliminated. Moreover, blind individuals did not possess any advantage in cognitive executive functions, such as manipulation of items in memory and math abilities. We propose that the short-term memory advantage of blind individuals results from better stimulus encoding, rather than from superiority at subsequent processing stages.