Differential effects of methylphenidate on problem solving in adults with ADHD.

OBJECTIVE: Two studies were performed to assess both divergent and convergent thinking in adults with ADHD. METHOD: The first study compared the problem-solving abilities of healthy participants (N = 144) and unmedicated adults with ADHD (N = 144). In the second study, problem-solving abilities of adults with diagnosed ADHD (N = 22) were examined twice, that is, on and off methylphenidate (MPH), and compared with the performance of a healthy control group (N = 22). Convergent thinking was measured using a Tower of London task, whereas divergent thinking was assessed using verbal fluency tasks. RESULTS: Adults with ADHD off MPH displayed marked deficits of both divergent and convergent thinking. MPH treatment resulted in a marked improvement of convergent thinking, while no effect of medication was found regarding divergent thinking. CONCLUSION: Pharmacological treatment of adults with ADHD revealed a differential effect of MPH on problem solving abilities.

Vigilance and sustained attention in children and adults with ADHD.

OBJECTIVE: The present article tests the hypothesis of a sustained attention deficit in children and adults suffering from ADHD. METHOD: Vigilance and sustained attention of 52 children with ADHD and 38 adults with ADHD were assessed using a computerized vigilance task. Furthermore, the attentional performance of healthy children (N = 52) and healthy adults (N = 38) was examined. RESULTS: Children and adults with ADHD performed significantly less well in the vigilance task than healthy participants (main effect for group). Furthermore, children and adults showed a significant decrease of performance over time (time-on-task effects). However, there was no greater decrement of performance with the passage of time in patient groups than in control groups (group-by-time interaction). CONCLUSION: The present results do not support the hypothesis of a sustained attention deficit in children and adults with ADHD.

Clustering and switching on verbal and figural fluency functions in adults with attention deficit hyperactivity disorder.

INTRODUCTION: Neuropsychological studies of adult patients with ADHD have revealed marked disturbances of executive functions including impairments of attention, working memory, impulsivity, shifting, and divergent thinking. Phonemic fluency tasks, in particular, have been shown to be sensitive measures for the assessment of executive functions of adults with ADHD. METHODS: The present study has examined figural fluency and both phonemic and semantic verbal fluency in 34 adult patients with ADHD and 34 healthy participants. For evaluation of fluency performance the number of words or designs, the number of repetitions and the number of deviations from test rules were calculated. Furthermore, clustering strategies and switching responses were analysed. In comparison with healthy participants, patients with ADHD produced significantly fewer words or designs, but they did not differ from healthy participants in the number of repetitions or rule violations. RESULTS: Analysis of switching and clustering showed that patients produced significantly fewer switching responses on both verbal fluency tasks, although patients tended to generate smaller clusters. Switching on the figural fluency task was unimpaired. CONCLUSIONS: The results of the present study suggest that adult patients with ADHD may suffer from a dysfunction that may affect retrieval processes and the categorisation of knowledge.

[Attention-deficit hyperactivity disorder and alcohol dependence: a risk constellation]. / Aufmerksamkeitsdefizit-Hyperaktivitätssyndrom (ADHS) und Alkoholabhängigkeit: Eine Risikokonstellation.

INTRODUCTION: The estimated prevalence for attention-deficit hyperactivity disorder (ADHD) in adulthood is 2 - 6 %. Patients with a substance use disorder met the criteria for ADHD between 30 and 50 %. ADHD and conduct disorders are discussed to increase risk of developing substance abuse and increase severity of disorder. METHOD: We compared epidemiological and clinical characteristics and comorbidity in subgroups of 314 adult alcoholics of German descent with or without persistent symptoms of attention-deficit hyperactivity disorder (ADHD). Aim of the study was to identify specific pathophysiological mechanisms that could contribute to vulnerability, severity or complication of alcohol dependence. RESULTS: 21.3 % of the alcoholics fulfilled DSM-IV-criteria of ADHD with ongoing symptoms in adulthood and had a Wender-Utah-Rating-Scale score > 90. Subgroup of alcoholics with ADHD were significantly younger at age of onset of alcoholism (24 years versus 30 years), had a significantly higher daily alcohol intake (253 g versus 196 g EtOH), had significantly more social stress, lifetime experiences in court proceedings against them (11 versus 2 %) and suicidal ideation (25 versus 11 %). In the subgroup of alcoholics with ADHD 51 % fulfilled criteria of antisocial personality disorder. The early onset of alcoholism was most pronounced in this subgroup. CONCLUSION: In our sample, persistence of ADHD symptoms from childhood into adulthood and antisocial personality disorder contributes to vulnerability and morbidity of alcohol dependence with early onset and greater severity of disorder.

[Attachment styles in German alcoholics with or without attention-deficit hyperactivity disorder (ADHD)]. / Bindungsstile bei deutschen Alkoholabhängigen mit und ohne Aufmerksamkeitsdefizit-Hyperaktivitätssyndrom (ADHS).

INTRODUCTION: Attachment theory yields empirical constructs for development of human self, personality and cognition. Insecure attachment strategies were associated with various psychiatric disorders. METHOD: We investigated distribution of attachment styles in 368 adult alcoholics of German descent with or without persistent symptoms of attention-deficit hyperactivity disorder (ADHD) and in 402 healthy individuals. RESULT: Insecure attachment styles were significantly overrepresented compared to healthy controls. The subgroup of alcoholics with ADHD showed significantly more frequent enmeshed (74.1 %), the subgroup of alcoholics without persistent ADH-associated symptoms showed more frequent dismissing (35 %) attachment strategies. CONCLUSION: In our sample, insecure attachment styles are associated with alcoholism. The subgroup of alcoholics with persistent ADHD shows a specific attachment behavior that could contribute to different therapy response or to early onset or severity of alcoholism.

[ADHD and alcohol dependence: a common genetic predisposition?]. / ADHS und Alkoholabhängigkeit: Gemeinsame genetische Grundlagen?

INTRODUCTION: Nearly 50 % of subjects with continuing symptoms of attention-deficit hyperactivity disorder (ADHD) in adulthood show a comorbid substance use disorder. Both, ADHD and alcohol dependence have a high genetic load and might even share overlapping sources of genetic liability. METHOD: We investigated phenotype and 5-HTT/5-HT2c allelic characteristics in 314 alcoholics of German descent. RESULT: 21 % of the alcoholics fulfilled DSM-IV-criteria of ADHD with ongoing symptoms in adulthood. There was no significant difference in 5-HTT- or 5-HT2c-allele distribution between alcoholics and matched controls or between alcoholics with or without ADHD. CONCLUSION: In our sample the functional relevant 5-HTT-promoter and the 5-HT2c-receptor Cys23Ser polymorphism do not contribute to the supposed common genetic predisposition of ADHD and alcohol dependence.