Influence of emotional stimulus valence on inhibitory control in adults with and without ADHD.

Human behavior is influenced both by approach and avoidance automatic reactions to positive and negative stimulus, respectively, but these reactions have not been well studied in attention-deficit/hyperactivity disorder (ADHD) patients. Moreover, studies employing spatial stimulus-response compatibility tasks in ADHD and healthy control (HC) subjects are scarce and inconclusive. The present study investigated inhibitory control and emotional processing in ADHD adults with a modified stimulus-response compatibility task in which spatial and emotional features of affective stimuli had to be processed together to select the correct response. Manual responses to figures of Favorite and Rival soccer team players were measured, and compatible or incompatible responses were chosen according to the soccer team figure. Eighteen HC participants and sixteen ADHD adults performed the task. We found an ordinary spatial compatibility effect for the Favorite soccer team and a reversed one for the Rival team in the ADHD group but not in the HC group. The effects may be due to stronger approach and withdrawal reactions toward the Favorite soccer team and away from the Rival one, respectively, indicating poor inhibitory control for the ADHD group. These results show that differences between ADHD and HC subjects become prominent when response selection involves both emotional and spatial features of the stimulus.

Cognition and impulsivity in adults with attention deficit hyperactivity disorder with and without cocaine and/or crack dependence.

BACKGROUND: Substance use disorder (SUD) is a common comorbidity in adults with attention deficit-hyperactivity disorder (ADHD). However,there have been few studies on cognitive profiles of these patients. Impulsivity is also commonly increased in both disorders. The central aim of this study was to compare cognition and impulsivity in subjects who had ADHD and cocaine dependence (ADHD+COC group) to those with ADHD only (ADHD-noSUD group). We hypothesized that the ADHD+COC group would show more marked cognitive dysfunction and greater impulsivity than their counterparts with ADHD only. METHODS: A total of 70 adult patients diagnosed with ADHD according to (DSM-IV-TR) criteria were enrolled; 36 with ADHD+COC and 34 with ADHD-noSUD. All study participants were evaluated with a sociodemographic questionnaire; the Mini International Neuropsychiatric Interview; the Adult ADHD Self-Report Scale; the Addiction Severity Index; the Alcohol, Smoking and Substance Involvement Screening Test; the Barratt Impulsiveness Scale; and a comprehensive neurocognitive battery. RESULTS: Compared to individuals with ADHD-noSUD, ADHD+COC individuals had significantly lower mean IQ and higher motor impulsivity. On average, the ADHD+COC group also performed more poorly on tasks assessing verbal skills, vigilance, implicit learning during decision making, and ADHD-noSUD performed more poorly on selective attention, information processing, and visual search. CONCLUSIONS: Our results support the integrative theory of ADHD based on the cognitive and affective neuroscience model, and suggests that ADHD-noSUD patients have impairments in cognitive regulation, while ADHD+COC patients have impairments in both cognitive and affective regulation.