Causes Of Attention Deficit Hyperactivity Disorder Research Articles

Knowledge of attention/deficit hyperactivity disorder (ADHD) – a comparison of pre-service teachers in primary and special education in Germany

<b>Background</b><br /> Given that the majority of children with attention deficit hyperactivity disorder (ADHD) attend regular classroom settings in Germany, it is necessary for teachers to be well prepared to provide these children appropriate care and education on the basis of accurate knowledge of ADHD. Pre-service teachers should have enough learning possibilities in their curriculum about ADHD. The purpose of this study was to investigate German pre-service teachers’ knowledge of ADHD by differentiating between their future school type, their study progress, their learning experiences, gender, and age.<br /> <br /> <b>Participants and procedure</b><br /> The participants were 234 pre-service teachers of the University of Leipzig, Germany. The survey instrument constructed by Lee (2015) was slightly modified for pre-service teachers, and consists of the three subscales: (a) characteristics of ADHD, (b) causes of ADHD, and (c) subtypes of ADHD.<br /> <br /> <b>Results</b><br /> Total accuracy of the knowledge of German pre-service teachers was 51.60%, inaccuracy was 21.60%, and no information was 25.80%. German pre-service teachers who majored in special education have a significantly higher accuracy rate than those who majored in primary education. The knowledge profiles consisting of total knowledge score and three domain-specific subscores can be explained significantly (ANOVAs) by the main effects and the interactions among the independent factors (a) future school type, (b) study progress, (c) experience by curriculum, and (d) personal experience. It was possible to discriminate significantly four pre-service teacher groups (differentiated by future school type and study progress) on the basis of their knowledge profiles by a discriminant analysis.<br /> <br /> <b>Conclusions</b><br /> Teachers are an important target group for ADHD research because they play a major role in early diagnosis of ADHD as well as supporting their development. During their education, pre-service teachers need to be prepared for dealing appropriately with ADHD children in the classroom. This study provides a basic investigation of German pre-service teachers’ needs of learning how to deal with ADHD children.

Practitioner Review: What have we learnt about the causes of ADHD?

BackgroundAttention deficit hyperactivity disorder (ADHD) and its possible causes still attract controversy. Genes, pre and perinatal risks, psychosocial factors and environmental toxins have all been considered as potential risk factors.MethodThis review (focussing on literature published since 1997, selected from a search of PubMed) critically considers putative risk factors with a focus on genetics and selected environmental risks, examines their relationships with ADHD and discusses the likelihood that these risks are causal as well as some of the main implications.ResultsNo single risk factor explains ADHD. Both inherited and noninherited factors contribute and their effects are interdependent. ADHD is familial and heritable. Research into the inherited and molecular genetic contributions to ADHD suggest an important overlap with other neurodevelopmental problems, notably, autism spectrum disorders. Having a biological relative with ADHD, large, rare copy number variants, some small effect size candidate gene variants, extreme early adversity, pre and postnatal exposure to lead and low birth weight/prematurity have been most consistently found as risk factors, but none are yet known to be definitely causal. There is a large literature documenting associations between ADHD and a wide variety of putative environmental risks that can, at present, only be regarded as correlates. Findings from research designs that go beyond simply testing for association are beginning to contest the robustness of some environmental exposures previously thought to be ADHD risk factors.ConclusionsThe genetic risks implicated in ADHD generally tend to have small effect sizes or be rare and often increase risk of many other types of psychopathology. Thus, they cannot be used for prediction, genetic testing or diagnostic purposes beyond what is predicted by a family history. There is a need to consider the possibility of parents and siblings being similarly affected and how this might impact on engagement with families, influence interventions and require integration with adult services. Genetic contributions to disorder do not necessarily mean that medications are the treatment of choice. We also consider how findings might influence the conceptualisation of ADHD, public health policy implications and why it is unhelpful and incorrect to dichotomise genetic/biological and environmental explanations. It is essential that practitioners can interpret genetic and aetiological research findings and impart informed explanations to families.

What Causes ADHD?

Attention-deficit hyperactivity disorder (ADHD) is the most common childhood neurobehavioral disorder, and often co-occurs with psychiatric (ie, anxiety, depression, oppositional defiant, or conduct), developmental (ie, learning and language or autism spectrum), and physical disorders (ie, tics, sleep apnea).1 A spate of recent articles reveals the complexity and conundrums of diagnosis and therapy. Thapar and colleagues from the Department of Psychological Medicine and Neurology and the MRC Centre in Neuropsychiatric Genetics and Genomics at Cardiff University, United Kingdom reviewed the literature on the causes of ADHD.2 They report that genetic studies have yielded largely inconsistent results but that genes regulating dopaminergic pathways appear to be involved in the pathogenesis of ADHD. Functional polymorphism in …

Knowledge of attention deficit hyperactivity disorder (ADHD) and attitudes toward teaching children with ADHD: THE role of teaching experience

AbstractKnowledge of attention deficit hyperactivity disorder (ADHD) and attitudes toward teaching children with ADHD are compared across stages of Australian teachers' careers. Relative to pre‐service teachers with (n = 218) and without (n = 109) teaching experience, in‐service teachers (n = 127) show more overall knowledge of ADHD, more knowledge of characteristics and treatments for ADHD, and higher perceived knowledge. In‐service teachers reported less favorable emotion about teaching children with ADHD than did pre‐service teachers without experience and more favorable behaviors than pre‐service teachers with experience. Groups did not differ in knowledge of causes of ADHD, overall attitudes, stereotypical beliefs, and beliefs about teaching children with ADHD. Identification of knowledge gaps and ambivalent attitudes will guide pre‐service and in‐service training courses. © 2012 Wiley Periodicals, Inc.

ADHDgene: a genetic database for attention deficit hyperactivity disorder

With a worldwide prevalence of ∼5%, attention deficit hyperactivity disorder (ADHD) has become one of the most common psychiatric disorders. The polygenetic nature of ADHD indicates that multiple genes jointly contribute to the development of this complex disease. Studies aiming to explore genetic susceptibility of ADHD have been increasing in recent years. There is a growing need to integrate the genetic data from various genetic studies to provide a comprehensive data set and uniform access for convenience of in-depth data mining. So far, there has been no such effort for ADHD. To address the genetic complexity of ADHD, we developed the ADHDgene database by integrating ADHD-related genetic factors by profound literature reading. Based on the data from the literature, extended functional analysis, including linkage disequilibrium analysis, pathway-based analysis and gene mapping were performed to provide new insights into genetic causes of ADHD. Moreover, powerful search tools and a graphical browser were developed to facilitate the navigation of the data and data connections. As the first genetic database for ADHD, ADHDgene aims to provide researchers with a central genetic resource and analysis platform for ADHD and is freely available at http://adhd.psych.ac.cn/.

Twin study on transplacental-acquired antibodies and attention deficit/hyperactivity disorder — A pilot study

Objective We hypothesize that maternal transplacentally acquired antibodies may cause Attention Deficit/Hyperactivity Disorder (ADHD) symptoms years after birth, and tested the hypothesis in twins discordant for ADHD symptoms. Method In a pre-screened sample of 7793 same sex twin pair's (4–18 years) questionnaire data on hyperactivity and inattention was collected. Blood samples taken 5 days after birth from 190 ADHD-score discordant pairs (15% MZ) were analyzed for antibodies. Results Pneumococcus Polysaccaride 14 (PnPs14) was present in the ADHD high scoring twin more often than in the lower scoring twin ( P = 0.04). Conclusion Although the study provides no strong support for the hypothesis, infection or immunological factors may be one among several causes of ADHD. The genetic control obtained in a twin design may reduce the exposure contrast and a larger sample is needed to further explore the role of PnPs14 in the etiology of ADHD.

Assessment of teacher and school psychologist knowledge of Attention‐Deficit/Hyperactivity Disorder

AbstractThe purpose of this study was to investigate teacher and school psychologists' knowledge of Attention‐Deficit/Hyperactivity Disorder (ADHD). One hundred thirty‐two kindergarten through 12th‐grade general education teachers, special education teachers, and school psychologists responded to a 24‐item questionnaire concerning treatment and possible causes of ADHD. The results supported the hypothesis that school psychologists' knowledge level of ADHD would be significantly greater than the knowledge level of special and general education teachers, but did not support the hypothesis that the knowledge level of special education teachers would be significantly greater than the knowledge level of general education teachers. Increased years of professional experience was negatively associated with increased knowledge about ADHD. Implications and suggestions for future research are discussed. © 2009 Wiley Periodicals, Inc.

Children's Beliefs About Causes of Childhood Depression and ADHD: A Study of Stigmatization

Children's Beliefs About Causes of Childhood Depression and ADHD: A Study of Stigmatization

Implicit theories of the characteristics and causes of attention-deficit hyperactivity disorder held by parents and professionals in the psychological, educational, medical and allied health fields

Current best practice guidelines advocate a multidisciplinary approach to the diagnosis and management of attention-deficit hyperactivity disorder (ADHD). However, no research has yet examined whether parents and professionals share common beliefs about ADHD. This study examined the implicit beliefs about the characteristics and causes of ADHD held by parents and professionals in the psychological, educational, medical, and allied health fields. A total of 670 participants rated 46 characteristics and 29 causal explanations for ADHD. Principal component analyses identified five characteristic factors and six causal factors. There was a high degree of concordance between the groups in their beliefs about the characteristics and causes of ADHD. However, several important differences were also found. The implications of the overlap and differences between professional and nonprofessional groups, and the scientific literature are considered.

Modelo de autorregulación de Barkley aplicado al trastorno por déficit de atención con hiperactividad: una revisión

The aim of this study was to carry out a review of Barkley's model of self-regulation and executive functions (EF) applied to attention deficit hyperactivity disorder (ADHD).Our starting point was the discrepancy between the description and the explanation of the disorder; that is to say, on the one hand important advances have been made from the applied point of view, but on the other hand we still do not have an overall explanation of the problem. The causes of ADHD are then reviewed as regards both specific aetiological factors and the wider reaching explanatory models. In this latter case, as antecedents and contributions prior to the model of self-regulation, we examine Douglas's attentional model and three models based on the concept of behavioural inhibition: Quay's neurobehavioural, Schachar's competitive, and Sergeant and van deer Meere's energetic models. Barkley's model was initially based on 'behavioural inhibition', but eventually the limitations that were detected and new lines of research led him to advance towards self-regulation. The main components of the model are reviewed: behavioural inhibition processes, the very concept of self-regulation/self-control, the EF involved, and motor control. The model is applied to the behaviour and characteristics of children with ADHD, and its implications in the fields of evaluation and treatment are discussed. Finally, we outline some of its main controversies and, in the conclusions, its strong and weak points are highlighted.

Making Sense of ADHD: A Battle for Understanding? Parents' Views of Their Children Being Diagnosed with ADHD

Much of the extensive body VLf research into attention deficit hyperactivity disorder (ADHD) has concentrated on understanding the aetiology of the disorder. This research has generated a number of very different conceptualizations of ADHD, ranging from purely medical descriptions to theories that incorporate a range of social and psychological factors. Although a large amount of research has been undertaken in this area, little is known about the individual experiences of those directly affected by the disorder and, in particular, how parents make sense of the variety of different aetiological models. The aim of this study was to investigate this issue. The mothers of nine boys, aged between 8 and 11 years, agreed to participate in the study. One father also participated. In-depth interviews, following a semi-structured format, were held with each participant. Interviews were transcribed verbatim and analysed using a grounded theory approach. Data analysis revealed that the key issue for parents was the discrepancy in the way in which parents understood the causes of ADHD, as compared with the ways in which others viewed the disorder. Parents reported that they believed ADHD to be a biologically based disorder, but that they felt others considered the disorder to be related to psychological and social factors. The implications of these differing perspectives were as follows: (i) parents battled with professionals and family members to encourage them to share their views of the condition; (ii) parents felt blamed by professionals and family members for their sons' difficulties; and (iii) parents reported experiencing significant emotional distress as a result of the differing views.

A qualitative study of Australian GPs' attitudes and practices in the diagnosis and management of attention-deficit/hyperactivity disorder (ADHD).

The importance of general practice involvement in the care of attention-deficit/ hyperactivity disorder (ADHD) is increasing due to the rising numbers of patients who present with the disorder. It has been suggested by consensus bodies that GPs should be identifying and referring patients at the severe end of the ADHD spectrum and managing those with less severe symptoms. However, GPs' views of their role in ADHD care are unknown. Our aim was to explore the attitudes and practices of Australian GPs towards the diagnosis and management of ADHD. We conducted a series of focus groups to explore GPs' beliefs regarding the causes of ADHD, their perceived role in ADHD diagnosis and management and their views on the role of behaviour therapies and pharmacotherapies in ADHD management. The subjects were 28 GPs in six focus groups. GPs in this study did not want to be the primary providers of care for patients with ADHD. Participants indicated a preference to refer the patient to medical specialists for diagnosis and treatment of ADHD, and expressed low levels of interest in becoming highly involved in ADHD care. Concerns about overdiagnosis and misdiagnosis of the disorder, diagnostic complexity, time constraints, insufficient education and training about the disorder, and concerns regarding misuse and diversion of stimulant medications were the reasons cited for their lack of willingness. The Australian GPs in this study identify a role for themselves in ADHD care which is largely supportive in nature, and involves close liaison with specialist services.

Association analysis of monoamine oxidase A and attention deficit hyperactivity disorder.

Attention deficit hyperactivity disorder (ADHD) is a highly heritable disorder. Although the causes of ADHD are unknown, dopaminergic, serotonergic and nor-adrenergic pathways have been strongly implicated. Monoamine Oxidase A (MAOA) is involved in the degradation of all three of these neurotransmitters and therefore has been suggested as a strong candidate gene for ADHD. Animal and human studies have implicated MAOA and 5-HT in impulsive and aggressive behavior. We therefore additionally postulated that MAOA might be associated with a subtype of ADHD where aggressive and impulsive features are especially prominent. We have tested this hypothesis by genotyping two polymorphisms (the 30-bp VNTR in the promoter and the Fnu4HI 941T-->G) in MAOA that are associated with altered MAOA function. Our sample consisted of 171 British Caucasian children 6-16 years of age fulfilling DSM-III R, DSM-IV or ICD-10 criteria for ADHD/Hyperkinetic Disorder. Using case control analysis and then the TDT, no association was found between these two MAOA polymorphisms and ADHD. Case control analysis of the VNTR showed an association with a subgroup of children with comorbid conduct problems (OR = 2.0, 95% CI = 1.09, 3.5), and TDT analysis indicated a statistical trend toward association. Our findings highlight the importance of phenotype definition and the need for the MAOA VNTR to be further examined.

Neuroscience of attention-deficit/hyperactivity disorder: the search for endophenotypes.

Research on attention-deficit/hyperactivity disorder (ADHD), a highly prevalent and controversial condition, has, for the most part, been descriptive and atheoretical. The imperative to discover the genetic and environmental risk factors for ADHD is motivating the search for quantifiable intermediate constructs, termed endophenotypes. In this selective review, we conclude that such endophenotypes should be solidly grounded in the neurosciences. We propose that three such endophenotypes — a specific abnormality in reward-related circuitry that leads to shortened delay gradients, deficits in temporal processing that result in high intrasubject intertrial variability, and deficits in working memory — are most amenable to integrative collaborative approaches that aim to uncover the causes of ADHD.

The Comparison of Intelligence Efficacy According to Methylphenidate Administration in Attention Deficit Hyperactivity Disorder(ADHD) Patients

Background: The causes of ADHD(attention deficit hyperactivity disorder) are various, so it is impossible to understand the whole characteristics of ADHD, only with simple intelligence testing scales. We compared cognitive characteristics of ADHD group with normal controls with Korean Kaufman Assessment Battery for Children(K-ABC). It is well known to evaluate neuropsychological and cognitive aspects of the children. Materials and Methods: Age and sex matched 40 ADHD patients and 40 normal controls tested with the K-ABC. Each subscales compared between pre-treatment patients and controls, pre-treatment and post-treatment in patient group, post-treatment patients and controls. Results: Significant differences are observed in sequential processing, simultaneous processing, cognitive processing and achievement between pre-treatment patients and controls, and in gestalt closure between pre-treatment and post-treatment patients group. But there are no significant differences between pre-treatment patients and controls in gestalt closure and reading/decoding. Conclusions: Methylphenidate improved the scores of simultaneous scale, which means improvement of executive functions such as divided attention, analysis and organization. Methylphenidate also reduced distractibility.

Family study of girls with attention deficit hyperactivity disorder.

Because attention deficit hyperactivity disorder (ADHD) is relatively infrequent among girls, little is known about the causes of ADHD in girls. To help fill this gap in the literature, the authors assessed the familial transmission of ADHD in families ascertained through girls. Interviewers who were blind to diagnosis administered structured psychiatric interviews to 140 girls with ADHD and their 417 first-degree relatives and to 122 girls without ADHD and their 369 first-degree relatives. The relatives of the ADHD girls had a significantly higher prevalence of ADHD, according to either the DSM-III-R or DSM-IV definition, than the relatives of the comparison girls. However, this did not differ from the prevalence the authors reported previously for families of boys with ADHD. Like the boys' families, the relatives of the girl probands also had significantly higher prevalences of antisocial, mood, anxiety, and substance use disorders, although the prevalence of familial antisocial disorders was lower than had been observed in the boys' families. There was no association between the DSM-IV subtypes of the probands and relatives. The familial transmission of ADHD and comorbid disorders generalizes to families of girls with ADHD. Neither proband gender nor subtype influences the familial transmission of ADHD.

National Institutes of Health Consensus Development Conference Statement: Diagnosis and Treatment of Attention-Deficit/Hyperactivity Disorder (ADHD)

Attention-deficit/hyperactivity disorder (ADHD) is a commonly diagnosed behavioral disorder of childhood that represents a costly major public health problem. Despite progress, ADHD and its treatment have remained controversial, especially the use of psychostimulants for both short- and long-term treatment. Although an independent diagnostic test for ADHD does not exist, there is evidence supporting the validity of the disorder. Studies (primarily short-term, approximately 3 months), including randomized clinical trials, have established the efficacy of stimulants and psychosocial treatments for alleviating the symptoms of ADHD and associated aggressiveness and have indicated that stimulants are more effective than psychosocial therapies in treating these symptoms. Because of the lack of consistent improvement beyond the core symptoms and the paucity of long-term studies (beyond 14 months), there is a need for longer-term studies with drugs and behavioral modalities and their combination. Although trials are under way, conclusive recommendations concerning treatment for the long term cannot be made at present. There are wide variations in the use of psychostimulants across communities and physicians, suggesting no consensus regarding which ADHD patients should be treated with psychostimulants, and thus the need for improved assessment, treatment, and follow-up. Furthermore, the lack of insurance coverage, preventing the appropriate diagnosis and treatment of ADHD, and the lack of integration with educational services are substantial barriers and represent considerable long-term costs for society. Finally, after years of clinical research and experience with ADHD, knowledge about the cause or causes of ADHD remain largely speculative. Consequently, there are no documented strategies for the prevention of ADHD.

Hyperactivity and Learning Deficits in Transgenic Mice Bearing a Human Mutant Thyroid Hormone β1 Receptor Gene

Resistance to thyroid hormone (RTH) is a human syndrome mapped to the thyroid receptor beta (TRbeta) gene on chromosome 3, representing a mutation of the ligand-binding domain of the TRbeta gene. The syndrome is characterized by reduced tissue responsiveness to thyroid hormone and elevated serum levels of thyroid hormones. A common behavioral phenotype associated with RTH is attention deficit hyperactivity disorder (ADHD). To test the hypothesis that RTH produces attention deficits and/or hyperactivity, transgenic mice expressing a mutant TRbeta gene were generated. The present experiment tested RTH transgenic mice from the PV kindred on behavioral tasks relevant to the primary features of ADHD: hyperactivity, sustained attention (vigilance), learning, and impulsivity. Male transgenic mice showed elevated locomotor activity in an open field compared to male wild-type littermate controls. Both male and female transgenic mice exhibited impaired learning of an autoshaping task, compared to wild-type controls. On a vigilance task in an operant chamber, there were no differences between transgenics and controls on the proportion of hits, response latency, or duration of stimulus tolerated. On an operant go/no-go task measuring sustained attention and impulsivity, there were no differences between controls and transgenics. These results indicate that transgenic mice bearing a mutant human TRbeta gene demonstrate several behavioral characteristics of ADHD and may serve a valuable heuristic role in elucidating possible candidate genes in converging pathways for other causes of ADHD.

Etiology of Attention-Deficit Hyperactivity Disorder

The most convincing and consistent data indicate that genetic etiologic factors are most important in attention-deficit hyperactivity disorder (ADHD). These factors may be mediated by a single major gene. Environmental studies remain heavily confounded. The last decade has seen considerable useful research on the causes of ADHD. Future investigations are promising.