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The Science of ADHD: A Guide for Parents and Professionals

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Abstract

Attention deficit hyperactivity disorder is a long-term disorder affecting many children and adults. It is also a highly controversial psychiatric disorder, in its cause, its diagnosis, and the effect of diagnosis on the patient. This controversy is exacerbated by the commonly recommended treatment for the condition---Ritalin. The science of ADHD addresses the scientific status of ADHD in an informed and accessible way, without recourse to emotional or biased viewpoints. The very latest studies are used to present a reasoned account of ADHD and its treatment. The science of ADHD is highly multidisciplinary, covering the areas of genetics, neuroscience, psychology, and treatment. The ever-increasing scientific evidence is described and discussed, informing the reader of the limitations of the science, but also the benefits that scientific inquiry can bring to understanding what goes on in the ADHD brain. (PsycINFO Database Record (c) 2012 APA, all rights reserved)(cover)
... Dominant conceptual models of ADHD highlight impairments to executive function and self-regulation (Loe & Feldman, 2007;Nigg, 2001). Other psychological models of ADHD also emphasize cognitive and neuropsychological risk (Brown, 2005;Gray & McNaughton, 2003;Sergeant, 2005), as well as neurological and biochemical risk (see Barkley, 2006;Chandler, 2010 for summaries). In addition to these is research demonstrating comorbidities (e.g., specific learning disabilities, anxiety) with ADHD that further compound difficulties with academic outcomes (Bauermeister et al., 2007). ...
... If the effects of ADHD are largely ameliorated once these covariates are entered, then clearly covariates are pivotal factors and intervention is to be directed to the covariates of relevance. To the extent that ADHD effects remain significant after entering covariates, then intervention is also to be directed at ADHD itself (e.g., toward executive functioning, medication, or self-regulation, which have been shown to be central to ADHD; Chandler, 2010;DuPaul & Stoner, 2003;Pliszka, 2009). In addition, because multiple dimensions of academic adversity (e.g., failure, grade repetition, school refusal, school exclusion, schoolwork noncompletion) are included as outcome factors, the study aims to shed expanded light on the particular mix of ADHD, personal, and contextual factors that best predicts particular adverse outcomes. ...
... These findings hold implications for practice, suggesting that multidimensional intervention targeting both ADHD and salient personal and contextual factors is necessary. Thus, for example, commonly recommended ADHD interventions involving medication, executive functioning (e.g., working memory, planning, control), and behavior (e.g., reward schedules) (Chandler, 2010;Pliszka, 2009) alongside commonly recommended intervention for specific learning disability (e.g., intensive reading intervention; Therrien, 2004) would target two of the factors predicting schoolwork noncompletion. ...
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Students with attention-deficit/hyperactivity disorder (ADHD) experience significant academic difficulties that can lead to numerous negative academic consequences. With a focus on adverse academic outcomes, this study seeks to disentangle variance attributable to ADHD from variance attributable to salient personal and contextual covariates. Responses from 136 students with ADHD and 3,779 non-ADHD peers from 9 high schools were analyzed using logistic regression. Dependent measures included academic failure, grade repetition, school refusal, changing classes and school, school exclusion, and schoolwork noncompletion. Covariates comprised personal (e.g., sociodemographics, personality, prior achievement, specific learning disabilities, motivation) and contextual (e.g., school size, school socioeconomic status, school average achievement) factors. Findings indicated that, after accounting for personal and contextual covariates, ADHD explained significant variance in numerous adversities (schoolwork noncompletion, school suspension, school expulsion, changing schools, grade repetition). Thus, beyond the effects of numerous personal and contextual covariates, ADHD has a distinct presence in students' academic adversity. Also interesting, after accounting for other personal and contextual factors, was academic adversity with which ADHD was not associated. Findings provide direction for educational intervention targeting ADHD and associated factors found to be significant in the study. (PsycINFO Database Record (c) 2014 APA, all rights reserved).
... This has given many parents bad conscious and hard feelings of blame and guilt. This problem is well-known in research and in a guide for parents and professionals Chandler (2010) argues that despite the dramatic increase in the diagnosis and treatment of ADHD the disorder is not new. The topic has been highlighted in a number of reports, e.g. the International Consensus Statement on ADHD (Barkley, 2002). ...
... ADHD is an ever increasing disorder among children especially in the western world and one reason for experiencing an increase is probably that we nowadays have opportunities to detect the disorder easier and have access to instruments to diagnose these children (Chandler, 2010). The disorder has been the focus of a large number of scientific and clinical studies over the last centuries and one of the front figures in Sweden is Gillberg (2005), who early noticed the difficulties the disorder caused children with DAMP and ADHD in school. ...
... Also the parents need knowledge of ADHD and what implications it has on the child's daily life. In many countries special parent education is organized where the parents of a child with disorder can meet other parents with the same interests (Chandler, 2010). Intervention must always involve the child's entire situation both at home and at school and the methods used for treatment should be evidence-based in order to be successful. ...
... In community samples it has been found that ADHD is about 2.3 times more common in males than in females (Ramtekkar et al. 2010;Bauermeister et al. 2007). In clinical samples the male-to-female ratio is found to be much higher than in community samples, suggesting that females with ADHD may be underdiagnosed (Skounti et al. 2007; see also Chandler 2010;Bauermeister et al. 2007). ...
... Such difficulties hamper an individual's social functions during different phases of life. For example, they may cause problems for individuals with ADHD in relationships with peers and school performance as well as problems in family life and employment (Chandler 2010;Taanila et al. 2009). ...
Chapter
Attention deficit hyperactivity disorder is a common neuropsychiatric disorder diagnosed on the basis of inattention as well as hyperactivity and impulsivity symptoms. These symptoms include and cause many kinds of pragmatic difficulties. These difficulties are manifested both in terms of understanding and expressing verbal and nonverbal language. Reported difficulties include, for example, excessive talking, poor conversational turn-taking, problems in topic maintenance, lack of coherence in narratives, difficulties in paying attention to relevant factors in communication and difficulties in understanding irony. Individuals with ADHD also often have difficulties with social perception (e.g. advanced theory of mind), language and other neuropsychiatric skills that, for their part, weaken the pragmatic language skills. Pragmatic and social language difficulties may increase social and societal difficulties of individuals with ADHD.
... Of particular concern though are the environmental causes given that nutrition, poor childhood care, fetal alcoholism and prenatal exposure to substances have been found to increase the risk of this disorder development (Heward, 2011). It is worth mentioning that inadequate parental care and dysfunctional family structure in general do exacerbate the symptoms but they are not to blame for its appearance (American Psychiatric Association, 2013;Chandler, 2010 With regard to the frequency rate of ADHD, it is estimated that there is at least one student with ADHD in each class (Barkley, 2006), while, in relation to Greek data, the rate approaches 6.5%, with boys having more chances of developing this disorder compared to girls (Skounti, Philalithis, Mpitzaraki, Vamvoukas, & Galanakis, 2006). This clear difference can be easily explained taking into consideration the boys' more dynamic and impulsive behavior, which is perceived as annoying by both parents and teachers and thus can more easily lead to monitoring and diagnosis. ...
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1. Abstract The main purpose of this article is to investigate and describe the difficulties faced by children with ADHD and to analyze the most appropriate educational approaches in relation to them. These approaches intend to help students reach a better coordination in the work they undertake each time as well as to improve their organizational skills in order to boost both their academic productivity and social performance. Behavioral strategies include both behavior reinforcement and self-monitoring teaching. To realize this objective a brief literature review has been conducted in order to provide concrete information and convincing arguments both from the Greek and international literature. Finally, although the expected positive effects of the objectives concerning the specific educational intervention are bibliographically confirmed, it is recommended that they be further examined through their application within classroom.
... Of particular concern though are the environmental causes given that nutrition, poor childhood care, fetal alcoholism and prenatal exposure to substances have been found to increase the risk of this disorder development (Heward, 2011). It is worth mentioning that inadequate parental care and dysfunctional family structure in general do exacerbate the symptoms but they are not to blame for its appearance (American Psychiatric Association, 2013;Chandler, 2010 With regard to the frequency rate of ADHD, it is estimated that there is at least one student with ADHD in each class (Barkley, 2006), while, in relation to Greek data, the rate approaches 6.5%, with boys having more chances of developing this disorder compared to girls (Skounti, Philalithis, Mpitzaraki, Vamvoukas, & Galanakis, 2006). This clear difference can be easily explained taking into consideration the boys' more dynamic and impulsive behavior, which is perceived as annoying by both parents and teachers and thus can more easily lead to monitoring and diagnosis. ...
... Gri madde, düĢünme ve öğrenme gibi iĢlevlerin yönetildiği birimken, beyaz madde, zihinsel iĢlevler ve sosyal beceriler üzerinde etkin bir rol oynamaktadır. ġu ana kadar yapılan çalıĢmalarda, DEHB' lilerde beyaz ve gri cevherde artma veya azalma olduğu tespit edilmiĢtir [4]. Klinik tanı için birçok hastalığın teĢhisinde gri ve beyaz madde hacmindeki değiĢikliklerin hesaplanması önemli bir kriterdir. ...
Poster
Attention Deficit hyperactivity disorder, which includes symptoms attention deficit, hyperactivity and impulsivity is brain disorder that affects millions of people .The ADHD specification differs from person to person. The method to be used in diagnosis should be objective and reliable. For this purpose, parameters obtained from brain imaging methods are an important component for diagnosis. As with many psychiatric disorders, the change in the ratio of gray and white matter is also significant in ADHD. The increase or decrease in these regions brings with it many problems. Gray or white matter plays an important role on social skills as well as on the development of mental skills, thinking and learning. For this purpose, we developed a unique method for obtaining gray and white matter, an important task in the diagnosis of ADHD. This method was tested on brain MRI data obtained from NP Istanbul Neuropsychiatric Hospital and results are compared.
... We also searched the literature published in China and abroad using keywords such as ADHD, rating scale, executive function, functional impairment, and evaluation, and referred to Barkley et al., Barkley, Brown, McCloskey, Chandler. [15][16][17][18][19] Regarding existing ADHD scales, we considered the PSQ, 13 CBCL, 20 SDQ, 14,21 Vanderbilt rating scale, 22 BRIEF, 23 WFIRS, 4 and IRS. 24 Each of these sources informed the original item pool. ...
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Objective This research developed a practical, multi-dimensional attention deficit hyperactivity disorder (ADHD) rating scale (i.e., the Symptoms and Functional Impairment Rating Scale, SFIRS) for Chinese children, aged 6–12 years, with ADHD. Methods The structural validity, criterion validity, internal consistency, and test-retest reliability of the scale were evaluated. Item screening was conducted with 412 ADHD patients and 322 developmentally typical controls. Results The scale includes 44 items, divided among Hyperactivity-Impulsivity, Self-Control, Inattention, Self-Management, Academic Performance, and Social Interaction. The six-factor model showed good data fit, with each factor significantly correlated with its corresponding criterion (r=0.690–0.841). The Cronbach's α of the full scale was 0.976. Total score test-retest reliability was r=0.816 (p<0.01). Conclusion The SFIRS thus demonstrated good reliability and validity and may be used to assess ADHD among children aged 6–12 years in China.
... It is known that there are biological differences between children with ADHD and children who are not diagnosed with ADHD, but understanding how these differences reflect to behaviour and to disorder could be understood due to understanding relationship between temperament and personality (Chandler, 2010). Temperament traits constitute structural ground of personality development (Yılmaz et al., 2014b). ...
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The purpose of this study is developing adolescent form (11-16 years old) of Nine Types Temperament Scale (NTTS) depending on Nine Types Temperament Model (Study 1) and evaluating and searching the relationship between Attention Deficit and Hyperactivity Disorder (ADHD) and Types of NTTM (Study 2). Sample of Study I consist of 1240 students who are between 11 and 16 years old. Pilot form of the Scale which consists of 90 items is tested with confirmatory factor analysis and with convergent and discriminant validity and the last version of the measure which consist of 82 items is prepared. Basic Personality Traits Inventory (BPTI) which depends on Fife Factor Model is used for Criterion-related validation. Results show that NTTS-A is valid and reliable measure for evaluating temperament types between 11-16 years adolescents. Their fit index is calculated as χ2/df <3; SRMR, 0.06; RMSEA, 0.045; CFI, 0.909: TLI, 0901 supported to validity data. Sample of Study II consist of 56 adolescents who are diagnosed with ADHD according to DSM-IV diagnosis criteria and 56 students who does not get diagnosed with ADHD or mental retardation/medical disorder. Temperament types of participants are evaluated by the agency of Study-I and NTTS-A, which is developed appropriate for Turkish culture. Indication of the study shows that there are more NTT7 and NTT8 in NTTM types between adolescents with ADHD than the group, who are not diagnosed with ADHD. As a result, it is discussed that traits which belong to some temperament types could have a predisposing effect on emergence of ADHD, experiencing these traits extreme severely could cause a view similar to ADHD and ADHD which is a neurodevelopmental disease could interact with temperament traits of person, in that way it could illustrate ADHD clinic. Available findings support critics about that students are labelled as ADHD specially in the last years in education environment even if they have mostly not developmental problems and students are diagnosed easily with limited observations. However, it is asserted that diagnosis based on temperament, treatment and psychosocial support programmes could be formed and effects of ADHD, which is a factor interacting with temperament traits, on personality structure of adolescents on their development process, could be predicted. Our study has the feature of being the first measure developing study which is intended to evaluate temperament types of adolescents between 11-16 years old and also it is has the feature of being the first study which searches relationship between NTTM types and ADHD.
... Bunun yanı sıra DEHB'e mizaç ve kişilik özellikleri açısından yaklaşmak, araştırmacı ve klinisyenlere hem tanı koyma hem de uyumsuz davranışların anlaşılması konusunda kolaylık ve anlayış sağlayabilir (Pauw ve Mervielde, 2011;Nigg ve diğ., 2004). DEHB'li çocuklarla DEHB tanısı olmayan çocuklar arasında biyolojik farklılıklar bulunduğu bilinmekte, ancak bu farklılıkların davranış ve bozukluğa nasıl yansıdığının anlaşılması, mizaç ve kişilik arasındaki ilişkilerin anlaşılmasıyla mümkün olabilmektedir (Chandler, 2010). Mizaç özellikleri, kişilik gelişiminin yapısal zeminini oluşturur (Yılmaz ve diğ. ...
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Bu çalışmanın amacı, Dokuz Tip Mizaç Modeli (DTMM)'ne dayalı olarak erişkinler için geliştirilen Dokuz Tip Mizaç Ölçeğinin (DTMÖ) 11-16 yaş arası ergen formunu (DTMÖ-E) geliştirmek (Çalışma I) ve DTMM tipleri ile Dikkat Eksikliği Hiperaktivite Bozukluğu (DEHB) arasındaki ilişkiyi incelemek ve değerlendirmektir (Çalışma II). Çalışma I'in örneklemi 11-16 yaş aralığındaki 1240 öğrenciden oluşmaktadır. 90 maddeden oluşan ölçeğin pilot formu doğrulayıcı faktör analizi, yakınsak ve ayırma (diskriminant) geçerliği ile test edilmiş ve ölçeğin 82 maddelik son hali hazırlanmıştır. Ölçüt geçerliği için ise Beş Faktör Modeli'ne dayanan Temel Kişilik Özellikleri Envanteri (TKÖE) kullanılmıştır. Sonuçlar, DTMÖ-E'nin 11-16 yaş arası ergenlerin mizaç tiplerini değerlendirmede kullanılabilecek geçerli ve güvenilir bir ölçek olduğunu göstermektedir. Uyum indeksleri χ 2 /df <3; SRMR, 0.06; RMSEA, 0.045; CFI, 0.909: TLI, 0901 olarak geçerlik verilerini destekler nitelikte hesaplanmıştır. Çalışma II'nin örneklemi ise DSM-IV tanı ölçütlerine göre DEHB tanısı almış 56 ergen ve mental retardasyon /
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The present study investigated the role of psychostimulants (methylphenidate, dexamphetamine; prescribed to participants for diagnosed attention-deficit/hyperactivity disorder; ADHD) in reducing the negative effects of hyperactivity-inattention (H-I) on achievement through elementary school. Whereas the bulk of research investigating H-I and medication has focused on students (conducting student-level analyses), research into classroom climates and processes suggests this issue be examined at both student- and classroom-levels. The sample comprised 54,165 Australian students (from 5419 classrooms) for whom H-I data were available in kindergarten and achievement data were available in year 3 and year 5. In preliminary variance components analyses, findings showed there was notable variation in H-I and psychostimulant status from classroom to classroom. In multilevel path analysis, at both student- and class-levels psychostimulants reduced the negative effects of H-I on student achievement, to a level where H-I had no significant negative impact on achievement. These effects were not moderated by dosage or psychostimulant type. Taken together, our findings add to the body of effective multi-modal educational and psychological interventions used to enhance the achievement outcomes of individual students who present with ADHD and—of particular note and novelty in this study—the classrooms to which they belong.
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Academic buoyancy is students' capacity to successfully overcome setback and challenge that is typical of the ordinary course of everyday academic life. It may represent an important factor on the psycho-educational landscape assisting students who experience difficulties in school and schoolwork. This study investigated the role of academic buoyancy in the achievement and cognitive, affective and behavioural engagement of (1) students with attention-deficit/hyperactivity disorder (ADHD) and (2) 'regular' (or 'general') students residing in the same classrooms and schools. The study also sought to extend prior research into academic buoyancy by including previously neglected and potentially influential factors such as personality and socio-economic status. Participants were n = 87 high school students with ADHD, n = 3374 non-ADHD peers, and n = 87 randomly drawn non-ADHD students. Survey-based data were analysed using multigroup (ADHD, non-ADHD, randomly weighted non-ADHD) multivariate (multiple independent/covariate and dependent variables) path analysis. The findings revealed a significant and positive association between academic buoyancy and outcomes for students with ADHD that generalized to non-ADHD groups. On occasion where academic buoyancy effects differed between the groups, effects favoured students with ADHD. Furthermore, academic buoyancy explained significant variance in outcomes for both groups of students after covariates (age, gender, parent education, language background, socio-economic status, personality) were entered. It is concluded that there is merit in widely promoting and fostering academic buoyancy among ADHD and non-ADHD students alike - and that academic buoyancy explains variance in outcomes beyond major intrapersonal factors such as personality, socio-economic status, ethnicity, and the like.
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In light of recent evidence suggesting the academic benefits of personal best (PB) goals for students with attention-deficit/hyperactivity disorder (ADHD), this article explores practical approaches to implementing PB goals in the counselling and classroom context. Beginning with a brief summary of how and why PB goals impact academic outcomes and the relevance of this to students with ADHD, concrete steps to implementing PB goals are described. Following this, the broader concept of academic growth is discussed, along with some guidance as to how to operationalise growth approaches with students. Taken together, a greater focus on academically at-risk students’ personal trajectories is suggested as a potentially fruitful approach to enhancing their educational outcomes.
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We have studied treatment-seeking students with “learning problems,” or attention deficit hyperactivity disorder (ADHD), who misuse psychostimulants, such as methylphenidate, for academic performance enhancement. A voluntary survey of 53 undergraduate stimulant abusers revealed that 94.3% of participants had smoked marijuana and that was a more likely cause of the problems than ADHD. within the past month (32% smoking daily) . In the cases presented in this survey, as in the case presented by Dr. Wilens, cannabis use was the most likely cause of learning problems and psychostimulant-seeking behavior.
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The nicotinic acetylcholine receptor (nAChR) is the principal target-mediator of nicotine from smoking and chewing of tobacco. The effects of nicotine on offspring of pregnant smokers are widespread, ranging from altered neural development to increased susceptibility to addiction in adolescence. These facts underscore the importance of understanding nAChR functions in the prenatal mammalian brain. This chapter discusses the fundamental aspects of acetylcholine (ACh) receptors with which nicotine interacts in the context of potential effects on neural development and plasticity.
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One important goal of neuroscientists is to eventually understand complex behavioral adaptations of humans and other animals as explained by the structure and function of their brain tissues and principles of evolutionary biology. To this end, the dominant model in evolutionary psychology assumes that complex adaptations involving brain or any other tissue are precisely crafted for a specific function and are produced by genes whose alleles all have equal fitness (genetic homomorphism) because sexual recombination would disrupt adaptations produced by genes whose alleles have unequal fitness (genetic polymorphism). This genetically zoomorphic model maintains that humans and other animals have evolved universal neuronal circuits and behavioral adaptations, which in their sum constitute a species-typical nature (a universal human nature for Homo sapiens), and that almost all variation in adaptive behavior among same-sex individuals is due to environmental effects. Alternatively, we assert that a review of currently available data in neuroscience, biology, and psychology strongly suggests that complex adaptations involving brain and other tissues have many imperfections, different functions in different environments, and much polymorphism genetic variation. Our genetically polymorphic model accounts for all these data and predicts that humans and other animal species have evolved many nonuniversal complex behaviors (multiple species-typical behaviors or “human natures”) that differ genetically between males and females, as well as within males and within females. Variability in same-sex behavior is therefore due to both environmental and genetic variation. Our genetically polymorphic model reconciles fundamental assumptions of evolutionary psychology with basic principles of evolutionary biology, behavioral genetics, and neuroscience.
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Describes the Extended Attention Span Training (EAST) system for modifying attention deficits, which takes the concept of biofeedback one step further by making a video game more difficult as the player's brain waves indicate that attention is waning. Notes contributions of this technology to neuropsychology and neurology, where the emphasis is on cautious, conservative treatment of children with attention disorders. (HTH)
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Electrophysiology is a chronometric tool to describe the time course of mental operations: this technique is unsurpassed when precise accounts of the covert activity of the brain are required. The scope of investigation in psychiatric research ranges from genes to cognition, from neurology to mind. This contribution reviews the efficacy of electrophysiology in delineating causal mechanisms, taking attention deficit hyperactivity disorder (ADHD) as an example. We review key electrophysiological findings in the study of ADHD, which contribute to the aetiological framework. Further, it is suggested that electrophysiological studies that build on cognitive-experimental findings may direct future lines of investigation, especially in combination with genetic methodologies.
Article
Twenty-two boys with a diagnosis of ADHD were compared with 22 typically developing boys on an advanced theory of mind task and on two tasks measuring aspects of executive function. Parents completed rating forms measuring general social competence, as well as mentalizing and non-mentalizing social behaviours. There were no differences between the groups on the advanced theory of mind measure. The children with ADHD scored more poorly than controls on an inhibition task but not on a planning task once age and IQ had been covaried. Ratings of social competence were correlated with theory of mind and executive function ability for the typically developing controls but not for the children with ADHD. The results are discussed in terms of inhibitory and social information processing accounts of ADHD.
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This article is dedicated to the Memory of Professor Nadine Lambert, October 21 1926 - April 26 2006. There is a paradox that the amphetamine class of drugs used in the treatment of Attention Deficit Hyperactivity Disorder (ADHD) are also abused widely in society. This article reviews possible legal issues related to the topic and the historical discourse concerning addiction associated with the use of amphetamines and methylphenidate for the treatment of ADHD, Lambert's theories and the research counterclaims that are used to support the pharmaceutical manufacturer's report that 'adequate treatment of ADHD may reduce the risk of substance abuse'. There are limitations in the Lambert studies and also limitations with other studies in the area. Further research and independent scientific and statistical analyses are required to determine any definitive conclusion. The author concludes that the claim and counterclaims cannot easily be resolved without a significant independent international inquiry.
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The work of Mayberg and others in the functional imaging of psychiatric disorders and their treatment is elucidating the biological substrates that underlie psychiatric interventions, and promises to revolutionize the future of psychiatry. With the emphasis on brain circuits as a common foundation for psychotherapeutic change, the idea of separate schools begins to give way to a new model of psychotherapy. For example, instead of simply thinking of transference as a strictly psychoanalytic concept, therapists can be confident that the emotions, cognitions and behaviors displayed in front of them have been programmed by a combination of genes and experience. Consequently, the signs and symptoms that the therapist observes are objective manifestations of the internal processing patterns that shape the patient's responses to the neural representations which the therapeutic relationship elicits. The specific internal patterns whose maladaptive consequences have brought the patient to treatment are usually the result of many years of data processing by hippocampal-cortical circuits. Consequently, they can require significant time and effort to change. The psychotherapeutic process is an effective, structured, and neurobiologically definable method for decreasing the probability of the reactivation of old, maladaptive neural patterns, and catalyzing the creation and maintenance of a new set of adaptive synaptic patterns by which a patient can make sense of the world and respond effectively to its challenges.
Article
Background There is underdiagnosis of and low use of specialist services for attention-deficit hyperactivity disorder (ADHD). Aims To quantify the filters in the help-seeking pathway through primary care and to investigate factors influencing progress for children at risk of ADHD. Method A total of 127 children (5-11 years old) with pervasive hyperactivity who passed each filter (primary care attendance and general practitioner (GP) recognition of disorder) were compared with those who had not. Results Primary care attendance was only associated with parental perception of the behaviour as problematic (OR 2.11; 95% CI 1.11-4.03). However, GP recognition was related to both parent and child factors — parental request for referral (OR 20.83; 95% CI 3.05-142.08) and conduct problems (OR 1.48; 95% CI 1.04-2.12). GP non-recognition was the main barrier in the pathway to care; following recognition, most children were referred. Conclusions Parents can be regarded as the main gatekeepers for access to specialist services.
Article
Background: The National Institute for Health and Clinical Excellence (NICE) has been widely recognised as setting an international standard for high-quality health technology assessments (HTAs) including economic evaluation. Scope: A previous critical analysis of NICE Technology Appraisal No. 98 (TA98), evaluating methylphenidate, dexamphetamine and atomoxetine for the treatment of attention-deficit/hyperactivity disorder (ADHD) in children, revealed a number of issues, which must cast doubt on the robustness of the NICE approach when addressing a complex clinical decision problem. The exploration of potential underlying problems will be followed by a discussion of lessons for international healthcare policy-makers, and is intended to be an invitation to further debate and inquiry, not a presentation of definitive conclusions. Symptoms: Pertaining to the technology assessment report, potential problems were identified relating to an unnecessarily narrow scope, data search and selection strategy, the distinction between efficacy and effectiveness, data synthesis across studies and clinical effect measures, and limitations of the economic model. The appraisal process moderated the asserted ‘clear conclusions’ of the assessment but could not compensate for some of its gaps. Conclusions: It is suggested that key issues contributing to these problems may have included a separation of clinical and economic perspectives, a highly standardised reference case analysis that was followed schematically, the absence of an effective system for quality assurance of technology assessments, and transparency deficits of the economic evaluation. Further considerations for international policy-makers looking at NICE as a potential role model for HTAs are discussed, such as institutional context, the objectives of collectively financed healthcare and related value judgments, the reliance on QALYs as a universal and comprehensive measure of health benefits, the appropriate perspective for analysis, and process-related implications.
Article
Typical texts develop students’ knowledge while only minimally developing the general skills they will need for success in school and in life. The goal of our text is to assist students in acquiring the most important skills for facing the diverse challenges life presents. The book contains an overview of theories of intelligence, but itself is based in large part on a theory according to which individuals need creative skills to generate new ideas and a vision for the future, analytical skills to make sure that the vision is a good one, and practical skills to execute the ideas and to persuade other people of their value. The book considers key skills in problem solving, logical reasoning, analysis of arguments, knowledge acquisition, creative and practical thinking, automatizing information processing, and avoiding life traps that derail even the most intelligent among us. © Robert J. Sternberg, James C. Kaufman, and Elena L. Grigorenko and Cambridge University Press, 2008.
Article
Tourette Syndrome is characterized by multiple motor and one or more vocal tics. Once thought to be rare, many studies now suggest that the prevalence is about 1% of children aged 5–18 years. Psychopathology is common, occurring in over 80% of clinic cohorts. It is generally accepted that Tourette syndrome is inherited, but the genetic mechanisms appear more complex than they previously seemed to be, as evidenced by recent studies. Infections and pre- and peri-natal difficulties have also been suggested to be important in the aetiopathogenesis. Thorough assessment is imperative and multidisciplinary management is ideal. Treatment should be symptom targeted, and in mild cases, psycho education and reassurance for the patient and the family, may be sufficient. A newly described behavioural treatment is Habit Reversal Training, which is superior to psychotherapy. Medication may be necessary for more moderate individuals. In severe cases, the medical treatment is far from simple and referral to an expert may be advisable. Treatments that may be needed include Botulinum Toxin. The prognosis is better than once thought, particularly from the impairment point of view. One study has shown that parents of children with Tourette syndrome have increased mental health difficulties and care giver burden when compared to control parents. Literature on Tourette syndrome is increasing at an enormous rate and it is important to keep up to date with recent findings.
Article
Attention deficit hyperactivity disorder (ADHD) is a multifactorial disorder and both genetic and environmental factors have been implicated in its etiology. Yet, the interaction between genes and environment is seldom studied directly. This article considers the plausibility of nicotine exposure during prenatal development as well as postnatal factors in the etiology of ADHD. The few existent studies show inconsistent results, but provide preliminary evidence suggesting that nicotine exposure together with genes in the dopaminergic system confer risk for ADHD. Factors affecting resilience during prenatal and postnatal development remain virtually unexplored. Recommendations for future research are provided
Article
This article describes a case study in which a 7-year-old first grade boy (Phil) underwent neuropsychological assessment to determine the possible existence of attention deficit hyperactivity disorder. Subsequent performances on tests of attention and executive functioning were quite variable. Specifically, there were indicators of inattention, erratic response style, and executive dysfunction evidenced by a large number of commission errors. In addition, there were difficulties maintaining attentional focus in the presence of distracters, weaknesses in working memory, information processing speed, and difficulties with planning and inhibition. Treatment implications are subsequently described, particularly the growing use of computer-assisted cognitive training to address working memory and executive functioning. Finally, the article concludes with a discussion about how to employ neuropsychological results in an effort to meaningfully engage the family of an attention deficit hyperactivity disorder child in long-term therapy.
Currently in the United States a prostate cancer drug is being touted in a novel way: The primary benefit of the drug is claimed to be not that it reduces the risk of the disease, but rather that it reducestheriskofbeingtreatedforthedisease.''Menaregetting screened, discovering that they have cancers that may or may not be dangerous, and opting for treatments that can leave them impotent or incontinent . . . Preventing the cancer can prevent treatments that can be debilitating, even if the cancers were neverlethaltostartwith''(Kolata,2008,p.A1).Suchisthestate of doctor-patient communication: Most doctors and virtually all patients are unschooled in how meaningfully to compare the risks of foregoing versus undergoing treatment, and the patient's frantic desire to ''do something, now'' often trumps the doctor's ancient commitment to ''first, do no harm.'' The problem that Gigerenzer, Gaissmaier, Kurz-Milcke, Schwartz, and Woloshin address in this exemplar of interdisci- plinary and international collaboration could hardly be more pressing. Marshalling one study after another, they demonstrate that, across widely varying samples of health professionals, patients, and policymakers, in all countries studied, statistical illiteracy reigns supreme—often with catastrophic conse- quences for individualand public health. The media function as enablers of this problem. For example, while the author of the newspaper article quoted in the previous paragraph showed unusual journalistic insight by noting the irony of inoculating people against treatment rather than against disease, she still expressed the benefit of the drug in terms of relative risk re- duction (''dropping the incidence (of prostate cancer) by 30 percent''; Kolata, 2008, p. A1) rather than in the much- less-dramatic terms of absolute risk reduction recommended in these pages. Clearer risk communication would go far in helping patients make informed and intelligent trade-offs between the costs and the benefits of various medical interventions, including the nonintervention of ''let's wait and see.'' Innumeracy, as this monograph makes abundantly clear, is an enormous societal problem. Even if statistical literacy could be achieved by fol-
Article
Objective: The aim of the study was to compare the efficacy and safety of methylphenidate and pemoline in the treatment of children with attention deficit hyperactivity disorder (ADHD).Background: Although methylphenidate, pemoline, and dextroamphetamine are all approved for the treatment of ADHD in children, in 1998 methylphenidate constituted ∼70% of the market. To compare the efficacy of these 3 drugs in a large population of children and to assess adverse events associated with their administration, we conducted a retrospective descriptive study of 500 children treated for ADHD at a large teaching institution.Methods: The charts of 500 children aged 4 to 18 years treated for ADHD over a 12-month period at a university-affiliated pediatric neurology clinic were reviewed retrospectively. The author rated treatment success from 1 (poor) to 4 (excellent) and assessed adverse effects based on the children's records.Results: Methylphenidate was prescribed for 48% (n = 240) and pemoline for 49% (n = 245) of the patients. The mean treatment rating was higher for pemoline (3.5 vs 2.7). Discontinuation was higher in the methylphenidate group (32% [n = 77] vs 10% [n = 25]) for lack of efficacy but higher in the pemoline group (22% [n = 54] vs 5% [n = 12]) for adverse effects (primarily insomnia). No liver abnormalities were reported in either group.Conclusions: A higher percentage of pemoline- than methylphenidate-treated children had an excellent clinical response; however, they also had more adverse events.
Article
Objective To investigate the incidence of birth intervention/foetal distress in children with developmental delay syndromes (attention deficit disorder, attention deficit hyperactivity disorder, dyslexia, dyspraxia, obsessive compulsive disorder, Tourette's syndrome of childhood, autistic spectrum disorders). Methodology A population of 100 children aged 4–15 years and diagnosed with developmental delay syndrome(s) were investigated using a parental questionnaire to determine whether they had suffered any birth interventions or distress. These results were compared with an age- and gender-matched control group. Results On the basis of this relatively small study, significant risk of development delay syndrome(s) occurred with both foetal distress (p < 0.001) and Ventouse assisted delivery (p < 0.01).
Article
A form of the hyperkinetic syndrome, assumed to be a juvenile condition, has been found in an adult with a previously undiagnosed condition. The pathognomonic paradoxical calming of the hyperkinetic by amphetamine was shown in a 22-year-old man and further elucidated by quantitative self-estimation of mood following doubleblind administrations of dextroamphetamine sulfate and placebo. Compared to his response to placebo, he not only showed externally visible calming and depression, but also subjectively reported decreased anxiety, increased depression, and increased concentration, with no change in self-esteem.
Article
Background: Little is known about the predictive validity of hyperkinetic disorder (HKD) as defined by the Diagnostic Criteria for Research for mental and behavioral disorders of the tenth edition of the International Classification of Diseases (ICD-10; World Health Organization, 1993), particularly when the diagnosis is given to younger children. Methods: The predictive validity of HKD was evaluated over a 6-year period and compared to the predictive validity of DSM-IV attention-deficit/hyperactivity disorder (ADHD) in 95 4–6-year-old children who met full criteria for at least ADHD and 122 demographically-matched nonreferred comparison children. Diagnoses were based on structured assessments of both parents and teachers. Results: All children who met full criteria for HKD also met full DSM-IV criteria for ADHD, but only 26% of ADHD children met criteria for HKD. Children who met criteria for HKD (N = 24), children who would have met criteria for HKD but were excluded from the diagnosis because they concurrently met criteria for an anxiety disorder or depression (N = 16), and the remaining children who met DSM-IV criteria for ADHD (N = 55) all exhibited significantly more symptoms of ADHD and greater social and academic impairment during years 2–7 than nonreferred comparison children. Unlike the two other diagnostic groups, however, children who met strict criteria for HKD were not more likely than comparison children to be injured unintentionally or to be placed in special education. Conclusions: Both ICD-10 HKD and DSM-IV ADHD exhibit predictive validity over 6 years, but ICD-10 HKD appears to under-identify children with persistent ADHD symptoms and related impairment. Children who met criteria for DSM-IV ADHD but not HKD exhibited at least as much functional impairment over time as hyperkinetic children.
Article
The investigation capitalizes on a 28-year prospective longitudinal study of hyperactive (ADHD) and age mate control participants identified from among 5212 elementary school children in randomly sampled classrooms from grades kindergarten through 5. The participants were followed from childhood through adolescence and interviewed 3 times in adulthood to document their life histories and the ages and use of licit and illicit substances over the developmental course. The Children's Attention and Adjustment survey provided parent and teacher rating scales of the cardinal symptoms of ADHD—inattention, impulsivity and hyperactivity—as well as ratings of conduct problems. The ratings were available at baseline, making possible the classification of all of the participants by research diagnostic proxies for DSM-IV ADHD. The substance use data included the age of initiation into tobacco, alcohol, marijuana, cocaine, and amphetamines, daily smoking and lifetime use of the substances, and DSM-III-R diagnoses of psychoactive substance use disorder at an average age of 26. Survival analysis of the age of regular smoking showed that the severity of ADHD symptoms lowered the survival rate for regular smoking. Severity of conduct problems also lowered the survival rate. Stimulant treatment affected lower survival rates, and when participants were classified by the age when stimulant treatment stopped, a protective effect was evident: Regular smoking did not begin until stimulant treatment ended. But the protective effect was short-lived. Those who had been treated with stimulants were significantly more likely to be daily smokers in adulthood. Chi-square analysis of ADHD, problem behavior and stimulant treatment showed a significant association between ADHD and between stimulant treatment and DSM-III-R diagnoses of tobacco dependence, and cocaine dependence. ADHD was also significantly associated with amphetamine dependence. Childhood conduct problems were significantly associated only with tobacco dependence. ADHD and stimulant treatment were each significantly associated with daily smoking in adulthood. Stimulant treatment was associated as well with lifetime use of amphetamine, and conduct problems only with the lifetime use of marijuana. Logistic regression was used to model the prediction of psychoactive substance dependence and lifetime use. Being initiated into tobacco by age 13 increased the odds of dependence on all of the substances in the investigation. Severity of ADHD increased the odds of dependence on tobacco, cocaine, amphetamine, and cocaine/amphetamine when the contribution of other variables in the analysis was accounted for. Stimulant treatment increased the odds of dependence on tobacco, cocaine, and cocaine/amphetamine. The logistic regressions for lifetime use as the dependent variable showed that being initiated into tobacco by age 13 increased the risk for lifetime use of all of the substances. Having been treated with stimulants increased the odds of adult daily smoking and lifetime use of amphetamine and cocaine/amphetamines. ADHD and problem behavior did not increase the odds of either daily smoking or lifetime use of any of the substances. The study supported hypotheses that tobacco serves as a gateway substance for dependence and lifetime use of all of the substances investigated. Self-medication, problem behavior, and sensitization hypotheses were discussed as possible explanations for the findings.
Article
This article is a discourse analysis of two historical inquiries into what clinici-ans today call attention deficit hyperactivity disorder (ADHD). Of primary con-cern in this regard are psychodynamic perspectives towards ADHD symptoms, championed by psychoanalysts and psychologists, and neurological perspectives towards ADHD, which continue to favor a purely physiological approach to understanding the disorder. Those within the psychodynamic camp are inclined to view ADHD as an interactional difficulty between self and social environment - a condition best remedied by psychotherapy. Those within the neurological camp see ADHD as a specific brain process, whose effective treatment depends upon adequate psychopharmacology. This essay argues that both psychodynamic and neurological perspectives towards ADHD have strategized to legitimate one perspective through the expulsion of the other. Within the current era of ADHD nomenclature and treatment it is clear that neurological perspectives dominate the debate. However, neurological perspectives continue to be haunted by a considerable amount of skepticism, both nationally and internationally. Because of this it would be difficult to assert that neurological perspectives, though winning the “legitimation race” in contemporary understandings of ADHD, are entirely monolithic sources of ADHD knowledge.
Article
Aims: The purpose of the present study was to assess patterns of temperament and character in a clinical sample of Korean children with attention-deficit hyperactivity disorder (ADHD) and to investigate the relationship between patterns of temperament and character and the severity of ADHD symptoms. Methods: Fifty-one children who met DSM-IV criteria for ADHD and 51 age- and sex-matched healthy comparison subjects completed the Junior Temperament and Character Inventory (JTCI) and the DuPaul's ADHD Rating Scale (ARS-IV). Results: Children with ADHD had significantly higher scores of Novelty Seeking and lower scores of Self-directedness in both parents' rating and children's self-rating. In addition, low Self-directedness scores predicted higher total scores of ARS-IV. Conclusions: In a clinical sample of Korean children with ADHD, a distinct pattern of temperament and character was found. The current findings suggest that low Self-directedness may be related to the severity of ADHD symptoms.
Article
The ability of hyperactive children to maintain attention on three tasks was examined. One of the tasks, a Choice Reaction Time Task, measured attention for brief periods, while the other two measured sustained attention. Of the latter two, one was an experimenter-paced task (the Continuous Performance Test) and the other a self-paced task (the Serial Reaction Task). It was found that the hyperactive children were no different from their normal controls in their ability to direct their attention for brief periods. They were, however, significantly inferior to the controls in their ability to sustain attention, particularly on the experimenter-paced task.
Article
Guided by the goal of documenting the natural course of the life histories of a large sample of hyperactive children and their control counterparts, this research reports the extent to which prenatal, developmental, and health history factors distinguish hyperactive and control groups, as well as the relative contributions of the various medical factors. Results indicate that prenatal factors, rather than those occurring later in the child's medical history, are the best predictors of subsequent hyperactive diagnosis.
Article
On tests comparing 176 biological and adoptive parents of hyperactive and normal control children, biological parents of hyperactives evidenced more attentional difficulties, slower mean reaction times, and fewer correct recognitions than did the other parents. They showed no significant differences in impulsivity. A familial association between childhood hyperactivity and attentional deficits in the biological parents was suggested, as was the persistence of attentional difficulties as compared to impulse control problems.
Article
The hypothesis is tested that the response to dextroamphetamine in terms of activity, attention, impulsivity, and autonomic activity is similar in normal (N) and hyperactive (H) children. Fourteen N and 15 H boys had skin conductance (SC), heart rate (HR), and finger temperature (ST) recorded during rest, presentation of eight 75- dB tones, and a reaction time (RT) procedure on three occasions: off drug (Day 1) and after ingestion (double-blind) of placebo and of .5 mg/kg dextroamphetamine. Both N and H groups showed drug effects, compared to placebo, of reduced motor activity and impulsivity, improved attention (RT), increased HR and HR slowing during RT foreperiods, and decreased ST. Both groups also had decreases in SC responsivity but in different parts of the test. Placebo compared to Day 1 produced increased activity and autonomic arousal but no change in RT. Stimulant drugs thus have similar behavioral and autonomic effects in both N and H boys, but the beneficial effects on behavior do not depend critically on increases in arousal.
Article
The effects of the d and l isomers of amphetamine on self-stimulation responding were tested following acute and chronic administration. Tolerance and post-drug depression of responding occurred in tests with both isomers, indicating no role for p-hydroxynorephedrine (PHN) which is one of the metabolites of d-amphetamine. In the second experiment, d-amphetamine, methylphenidate and cocaine all produced quantitatively and qualitatively similar effects on self-stimulation responding following acute administration. Following chronic administration of d-amphetamine, animals showed tolerance to all three drugs, indicating cross-tolerance among them. These data are consistent with an hypothesis that tolerance and post-drug depression following chronic amphetamine treatment are the result of decreases in postsynaptic receptor sensitivity, which would lead to a decreased effectiveness of all three drugs, regardless of their pre-synaptic mechanisms.
Article
This commentary shows that Joseph's (this issue) review of the genetics of attention deficit hyperactivity disorder (ADHD) contains errors of scientific logic and ignores much relevant research. Thus, we reject his conclusions. We also reject Joseph's approach of pitting nature against nurture as if these two facets of human life are at odds with one another. Instead, most scientists who study the genetics of psychiatric disorders embrace the idea that these disorders are influenced by both genes and environmental factors. In fact, the twin studies criticized by Joseph provide the strongest evidence that environmental risk factors play a substantial role in the etiology of ADHD. They do so by showing that when one identical twin has ADHD the risk to the co-twin is much less than 100%, a fact which can only be explained by environmental risk factors. We also reject the idea that genetic studies have hindered psychosocial research, stigmatized patients, or promoted psychopharmacologic treatments. Genetic studies have aimed at solving one part of the puzzle of ADHD. By testing a parsimonious theory, they have set the stage for gene discovery and the delineation of how genes and environment combine to cause this impairing disorder.
Article
This study is an extension of Colledge and Blair’s (2001) investigation on the inter-relationship between core features of attention deficit/hyperactivity disorder and conduct disorder. The current study extended the earlier work using methodological refinements in sample selection, psychiatric diagnostic assessment, and instruments used to measure inattention, hyperactivity, and psychopathy. The primary outcome was that the impulsiveness-conduct problem component of psychopathy was specifically associated with inattention and hyperactivity components of attention deficit/hyperactivity disorder. Impulsivity may be an underlying mechanism common to both disorders and may represent a selective target for treatment.
Article
In many respects, the epidemiology of autism is still in its infancy. Although important questions remain unanswered, epidemiologists are making significant progress in several areas of inquiry that will be addressed in this presentation: How common is autism? Has the prevalence changed over time? What demographic and environmental risk factors have been identified that may provide clues to underlying etiology? What research is being done to search for early biologic markers for autism and related disorders? Epidemiologists like to count “cases” to estimate the frequency with which autism occurs in a population. However, prevalence estimates are heavily influenced by the methodology used for identification of affected individuals, making it difficult to compare prevalence across different time periods or populations. Current estimates of autism prevalence based on different methodologies and factors contributing to observed time trends will be provided for consideration. The tools of epidemiology are also useful for identifying demographic and environmental risk factors that may provide clues to underlying etiology. Preliminary data will be presented from large California studies on characteristics of parents and newborns that are associated with risk of autism. Finally, in collaboration with basic scientists, slow progress is being made in identifying and evaluating early biologic markers for autism. Current studies will be described and preliminary data on newborns presented.
Article
Cluster analysis was used to investigate empirical typologies of inattention and hyperactivity-impulsivity traits and whether these traits would correspond to DSM–IV ADHD typologies. Parents rated 104 male and female children, aged 5 to 14.7 years, on a scale developed to operationalise DSM-IV (American Psychiatric Association, 1994) criteria. Cluster analysis revealed four ADHD typologies with possible developmental changes in hyperactive-impulsive behavior as children mature as well as two ‘normal’ subgroups. Results indicated that DSM–IV defined ADHD characteristics where present in a cross section of individuals including nonpsychiatric controls. The structure of ADHD characteristics reflected the DSM-IV Combined and Inattentive types but failed to support a robust hyperactivity-impulsivity subgroup. Post hoc analysis suggested this may be a result of developmental factors; wherein hyperactivity-impulsivity traits decrease with age and inattention remains relatively stable. Cluster analysis also suggests that ADHD symptoms are normal personality traits that become pathological at relatively high levels.
Article
Reward and punishment sensitivity are central constructs that play a major role in individual differences in personality. Yet, few studies have tested the relevance of these constructs for occupational health research. Therefore, we examined the relationship between reward sensitivity and punishment sensitivity with occupational well-being. In a sample of 245 teachers we found that beyond job characteristics, reward sensitivity was mainly associated with positive indicators of well-being (job satisfaction, involvement). Punishment sensitivity statistically predicted stress and fatigue. In addition, reward and punishment sensitivity significantly interacted with job characteristics, suggesting that they play a role in the way employees react to favourable or unfavourable working conditions. Results indicate that reward and punishment sensitivity, as defined in the Reinforcement Sensitivity Theory of Personality, are relevant constructs in occupational studies.
Article
Cerebrospinal fluid (CSF), plasma, and urinary monoamine metabolites were determined for 29 boys, aged 6–12, with attention-deficit hyperactivity disorder (ADHD). Levels of CSF 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid (HVA), and 3-methoxy-4-hydroxyphenylglycol (MHPG), the metabolites of serotonin, dopamine, and norepinephrine, respectively, correlated significantly with behavioral measures of aggression and impulsivity/hyperactivity. However, these correlations were in the unexpected direction; for example, CSF 5-HIAA correlated positively with the Brown-Goodwin Lifetime History of Aggression Scale. HVA in CSF was positively correlated with several measures of hyperactivity. The replicability of these findings, as well as possible socioenvironmental effects, and the predictive value of CSF monoamines in prepubertal hyperactivity are the subjects of ongoing study.
Article
Central dopaminergic activity has been assumed to play a role in the efficacy of stimulant drugs in attention deficit/ hyperactivity disorder (ADHD), although supporting evidence has been scant. This study examined baseline cerebrospinal fluid (CSF) of boys with ADHD in relation to response to three different stimulant drugs. Forty five boys with DSM-III-R-diagnosed ADHD had a lumbar puncture before double-blind trials of methylphenidate, dextroamphetamine, and placebo. Sixteen also received pemoline as part of a subsequent open trial. Stepwise linear regressions determined significant predictors of drug response. Our prior report of a positive significant correlation between CSF homovanillic acid (HVA) and ratings of hyperactivity on placebo was replicated in a new sample of 20 boys. After baseline symptom seventy, CSF HVA was the best predictor of stimulant drug response, with significant independent contribution to four of the ten measures of hyperactivity that changed significantly with medication. Higher HVA predicted better drug response, and lower HVA was associated with worsening on some measures. This supports the mediating role of central dopaminergic activity in stimulant drug efficacy in childhood hyperactivity.
Article
Platelet monoamine oxidase (MAO) activity was studied in 22 boys diagnosed as having attention deficit disorder with hyperactivity and 12 healthy control boys admitted to a clinical research center and placed on a diet low in monoamines. The hyperactive boys had lower platelet MAO activity than controls, and MAO activity was related to performance on the Matching Familiar Figures Test (MFF) and the Continuous Performance Test (CPT), which yield scores sensitive to impulsivity and inattention. Furthermore, it was negatively related, in hyperactive boys only, to two tests of reading and spelling achievement. Administration of d-amphetamine and placebo in a double-blind crossover design did not significantly raise MAO levels above baseline and was minimally related to improved performance on the MFF and CPT.
Article
Predicting which children with Attention Deficit-Hyperactivity Disorder (ADHD) will respond to methylphenidate (MPH; Ritalin) is of theoretical interest, for example, for understanding catecholamine contributions to self-regulation. Large individual differences in response to MPH and the wide prescription of MPH for ADHD have encouraged research on response prediction. We reviewed 59 studies conducted since the last major review by Barkley in 1976 and examined responder definition, comorbidities, demographics, intelligence, inhibitory control, physiological measures, and placebo response. Strong responders are more easily predicted; children with anxiety, who are older, or have less severe symptoms do not respond as well. Measures of inhibitory control and catecholamines are weakly associated. Prediction on a case-by-case basis is not possible, and group findings have not generalized well. Implications of these findings for the validity of the disorder are discussed.
Article
Following a week of habituation to an activity cage, the locomotor activity of mice following a single dose (0, 1.0, 2.5, 5.0, 7.5 or 15.0 mg/kg) of d-amphetamine was measured. At all doses except 0 (saline), the effect of d-amphetamine on activity was inversely correlated with pre-drug baseline activity. These results demonstrate rate-dependent effects of d-amphetamine on locomotor activity and suggest that hyperkinesis per se would predispose to a sedative action of amphetamines in minimal brain dysfunction.
Article
This article examines evidence cited in favor of the operation of genetic factors in attention-deficit hyperactivity disorder (ADHD). Like other psychiatric conditions, a belief in the genetic basis of ADHD is derived from the results of family, twin, and adoption studies. Because family studies are widely believed to be confounded by environmental factors, primary emphasis is placed on twin and adoption studies. ADHD twin studies depend on the validity of the equal environment assumption (EEA), which holds that the environments of identical (MZ) and fraternal (DZ) twins are the same. Here it is argued that however the EEA is defined, it cannot be accepted. Therefore, the greater similarity or concordance of MZ twins when compared to DZ twins is plausibly explained by environmental factors. Adoption studies constitute a third method for investigating the role of genetic factors in ADHD. It is argued that these studies are greatly flawed by factors including non blinded diagnoses and the failure to study the biological relatives of adoptees. After an examination of the total weight of evidence in favor of a genetic basis or predisposition for ADHD, it is concluded that a role for genetic factors is not supported and that future research should be directed toward psychosocial causes
Article
Despite considerable research, the validity of attention-deficit/hyperactivity disorder (ADHD) remains controversial. This paper summarizes the results of a comprehensive review of the internal and external validity of ADHD as defined in the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). Results indicate that for most individuals DSM-IV ADHD is a valid disorder in the sense that it is associated with significant impairment in social, academic, and occupational functioning and increased risk of accidental injury across the life span. Additional research is needed, however, to clarify the diagnostic validity of the hyperactive-impulsive type and the discriminant validity of the combined and inattentive subtypes. Other areas in need of further study include potential modifications to the diagnostic conceptualization of the inattentive subtype, developmental trajectories of the subtypes, and methods to address cross-informant diagnostic inconsistencies. Such research is likely to benefit from an etiologically informed approach to examining heterogeneity both across and within subtypes.
Article
The aim of the study is to present a new method for the segmentation of the caudate nucleus and use it to compare the caudate heads and bodies of an attention deficit-hyperactivity disorder (ADHD) group with those of a control group. We used a 1.5-T system to acquire magnetic resonance brain scans from 39 children with ADHD, as defined by DSM-IV TR, and 39 age, handedness and IQ matched controls. The new method for caudate head and body segmentation was applied to obtain semi-automatic volumes and asymmetric patterns. Bilateral volumetric measures of the head, body, and head-body of the caudate nuclei were compared within groups and between ADHD and control groups. Although the group factor was not significant, there were first and second order interactions. The analysis of simple effects showed that the right body and right head+body of the ADHD group was significantly smaller than in the control group, although the ADHD right caudate head was bigger. No ADHD within-group caudate differences were found. Controls showed a significantly larger left caudate head and a significantly bigger caudate right body and right head+body. Our new method for segmenting the caudate nucleus detected differential abnormalities of the right caudate head and body in the ADHD group, explaining previous heterogeneous findings in the literature.
Article
Previous studies, in which cognitive and motor neuropsychological tasks were administered to 816 children from Attention-Deficit/Hyperactivity Disorder (ADHD)- and control-families, showed that various of these measures appeared useful for genetic research in ADHD by forming candidate endophenotypes: underlying, heritable, vulnerability traits that mark an enhanced liability for developing ADHD. The current study extends these findings by showing that six of these ten measures correlate more strongly between siblings than an ADHD composite, suggesting these measures may have a larger heritability than ADHD itself. Significant sibling cross-correlations also suggested that six of ten neuropsychological measures related to similar familial (and heritable) factors as ADHD, suggesting these measures to be useful for ADHD genetic research. An aggregated neuropsychological composite appeared to be the most powerful, since it correlated more strongly between siblings than most individual task measures. These findings suggest heritability research in ADHD will probably be facilitated by including neuropsychological measures.
Article
An increasing debate exists about the potential of early exposure to methylphenidate to increase the risk for drug abuse. In addition, little is known about the neurobiological effects of early exposure to methylphenidate. This study was designed to investigate whether chronic treatment with methylphenidate induces behavioral sensitization to subsequent methylphenidate and D-amphetamine challenge in adolescent Wistar rats. Young Wistar rats (P25) were treated with either methylphenidate (1, 2, or 10 mg/kg, intraperitoneally) or saline for 28 days. After 14 days of washout, animals were challenged with methylphenidate 2.5 mg/kg intraperitoneally or D-amphetamine 2 mg/kg intraperitoneally (P67). Locomotor behavior was assessed using the open field test. Rats chronically treated with methylphenidate in the adolescent period showed augmented locomotor sensitization to D-amphetamine but not to methylphenidate in the adult phase. These findings suggest that early exposure do methylphenidate might increase the risk for subsequent D-amphetamine abuse. Further studies focusing on the neurobiological effects of early exposure to methylphenidate are warranted.
Article
New long-acting medications for attention-deficit/ hyperactivity disorder (ADHD) have become available, which combine certain advantages over conventional short-acting drugs with higher acquisition costs. Choices between these drugs should thus be driven by their clinical profiles and by an acceptable balance of increased costs and additional benefits. Accordingly, the notion of relative cost-effectiveness should be central to recommendations about the use of these drugs in practice. A recent technology assessment on behalf of the National Institute for Health and Clinical Excellence (NICE) did not identify differences between compounds in terms of clinical efficacy and described drug cost as the major driver of cost-effectiveness. The underlying economic model was restricted to a cost-utility analysis that used only a fraction of the available clinical evidence base and did not address the distinction between efficacy and effectiveness. Cost-effectiveness evaluations including the potential impact of improved treatment compliance indicate a relatively more attractive cost-effectiveness of long-acting medications than suggested by the NICE assessment. These evaluations provide health economic support to treatment recommendations recently published by the European Network for Hyperkinetic Disorders. Limitations of currently available economic evaluations include their short time horizon, and future research should assess treatment effects on long-term sequelae associated with ADHD.
Article
Psychiatric conditions and the institutions and practices that modern society has evolved to handle them originated during the nineteenth century in Anglo European societies. They are products of a historically contingent and culture specific formulation of a class of social problems of behavior that came to the fore in relation to intellectual and political economic changes of those societies. However, such problems have a long ancestry. They are intrinsic to human species and the social and cultural systems that its members have evolved since their emergence. This article reviews intellectual quandaries raised by evolutionary study of psychiatric conditions, those of crossing the human/animal divide and crossing historically contingent cultures; and of framing history of psychiatry in terms of social and cultural evolution. The biological architecture underlying psychiatric conditions and the breakthroughs that indigenous psychiatry of different types of societies underwent in formulating signs and symptoms are discussed.
Article
The behavioral effects of repeated methylphenidate (MPH) treatment were assessed in the adult rat. Protein kinase A (PKA) and adenylyl cyclase (basal and DA-stimulated) activity in the dorsal striatum (i.e., caudate-putamen) were measured to determine whether MPH-induced alterations in these enzymes correlate with the occurrence of behavioral sensitization. In two experiments, adult rats were injected (i.p.) on 5 consecutive pre-exposure days with saline or MPH (5, 10, 15, or 20 mg/kg). Sensitization was tested after a single abstinence day, with rats receiving a challenge injection of MPH prior to either a 40- or 150-min testing session (additional control groups received saline on the test day). Immediately after the 40-min testing session, rats were killed and tissue from the dorsal striatum was dissected for later analysis of PKA and adenylyl cyclase activity. Results showed that repeated MPH treatment sensitized the stereotyped sniffing, but not the locomotor activity, of adult rats. PKA activity was significantly depressed in rats treated with MPH (10 or 20 mg/kg) during both the pre-exposure and test day phases. DA-stimulated adenylyl cyclase activity was reduced after chronic MPH treatment, while basal adenylyl cyclase values were enhanced. Thus, the present study showed that MPH was able to sensitize the stereotyped behaviors of adult rats, an action that corresponded with drug-induced changes in dorsal striatal DA signal transduction mechanisms.