Objective:
Conduct disorder (CD) encompasses children and adolescents who show extreme antisocial behaviour and is commonly allied with attention deficit hyperactivity disorder (ADHD). This study focuses on the markers of facial emotion recognition, which discriminate ADHD from combined ADHD and CD, as well as healthy controls.
Method:
Children and adolescents with ADHD, with and without comorbid CD, were tested on the standardized Brain Resource International Database protocols and were compared with a group of matched healthy controls. Testing included a forced-choice facial emotion recognition task, from which response accuracy and reaction time were recorded.
Results:
ADHD (with and without comorbid CD) was distinguished from healthy controls by poorer recognition of negative facial expressions and a quicker reaction time to correctly identify angry facial expressions. However, ADHD alone was distinguished from both the healthy control and the combined ADHD and CD groups by poorer recognition of positive facial expressions and a longer response reaction time those that were correctly identified. Notably, the combined ADHD and CD group was not differentiated from healthy controls by either accuracy or reaction time to positive facial expressions.
Conclusions:
ADHD with combined CD comprises a diagnostic group with emotion-related cognitive deficits that are distinct from those showed in ADHD alone and indicate a difference in the causal mechanisms underlying social cognition and emotion recognition deficits between these groups. This difference underscores the relevance of taking comorbidity into account in addressing both emotional awareness and social and peer relationship difficulties in ADHD.
