Cognitive control and emotional response in attention-deficit/ hyperactivity disorder comorbidity with disruptive, impulse-control, and conduct disorders.

BACKGROUND: This study investigated cognitive and emotional functioning in children and adolescents with attention-deficit/hyperactivity disorder (ADHD) and disruptive, impulse-control, and conduct disorders (DICCD). METHODS: Thirty patients with ADHD, 26 with DICCD, 22 with ADHD+DICCD were recruited from the outpatient department of Shanghai Changning Mental Health Center, plus 20 healthy controls (HC). Differences between the groups in cognitive and emotional functioning were examined using Golden's Stroop and Emotional Stroop tests. For Emotional Stroop Mean reaction time (RT) of positive word (POS) and negative word (NEG) with color congruence (C) or incongruence (I) were recorded as POS-C, POS-I, NEG-C and NEG-I, respectively. RESULTS: For Golden's interference scores (IGs), both errors and RTs in the ADHD group were higher than in the other groups. Longer mean RTs of POS-C, POS-I, NEG-C and neural word (NEU) of the ADHD group, and NEG-I of ADHD+DICCD and DICCD groups were observed compared to HC. After 12 weeks of methylphenidate treatment, differences between ADHD subgroups and HC on Golden's Stroop RT disappeared, but differences in Golden's Stroop errors and Emotional Stroop mean RTs remained. The ADHD+DICCD group showed longer mean RTs in NEG-C, NEG-I and NEU of the Emotional Stroop test than the ADHD group. CONCLUSIONS: Our study shows that regardless of emotional responding, deficit in cognitive control is the core symptom of ADHD. However, emotionally biased stimuli may cause response inhibitory dysfunction among DICCD with callous-unemotional traits, and the comorbidity of ADHD and DICCD tends to account for the negative emotional response characteristic of DICCD. These deficits may be eliminated by medication treatment in ADHD, but not the ADHD with comorbid DICCD. Our results support the notion that ADHD with comorbid DICCD is more closely related to DICCD than to ADHD.

The Relationship between Neurocircuitry Dysfunctions and Attention Deficit Hyperactivity Disorder: A Review.

The prefrontal cortex is the superlative structure of brain that needs the longest developmental and maturational duration that highlights the region of attention deficit hyperactivity disorder (ADHD) in neuroimaging studies. Prefrontal cortex functions generate enormously complex and its abundant feedback neurocircuitries with subcortical structures such as striatum and thalamus established through dual neural fibers. These microneurocircuitries are called corticostriatothalamocortical (CSTC) circuits. The CSTC circuits paly an essential role in flexible behaviors. The impaired circuits increase the risk of behavioral and psychological symptoms. ADHD is an especial developmental stage of paediatric disease. It has been reported that the CSTC circuits dysfunctions in ADHD are related to homologous symptoms. This study aimed to review the symptoms of ADHD and discuss the recent advances on the effects of the disease as well as the new progress of treatments with each circuit.