Neural Basis of Impaired Emotion Recognition in Adult Attention-Deficit/Hyperactivity Disorder

Abstract

Background: Deficits in emotion recognition have been repeatedly documented in patients diagnosed with attention-deficit/hyperactivity disorder (ADHD), but their neural basis is unknown so far.

Methods: In the current study, adult patients with ADHD (n = 44) and healthy control subjects (n = 43) underwent functional magnetic resonance imaging during explicit emotion recognition of stimuli expressing affective information in face, voice, or face-voice combinations. The employed experimental paradigm allowed us to delineate areas for processing audiovisual information based on their functional activation profile, including the bilateral posterior superior temporal gyrus/middle temporal gyrus, amygdala, medial prefrontal cortex, and precuneus, as well as the right posterior thalamus.

Results: As expected, unbiased hit rates for correct classification of the expressed emotions were lower in patients with ADHD than in healthy control subjects irrespective of the presented sensory modality. This deficit at a behavioral level was accompanied by lower activation in patients with ADHD versus healthy control subjects in the cortex adjacent to the right superior temporal gyrus/middle temporal gyrus and the right posterior thalamus, which represent key areas for processing socially relevant signals and their integration across modalities. A cortical region adjacent to the right posterior superior temporal gyrus was the only brain region that showed a significant correlation between brain activation and emotion identification performance.

Conclusions: Altogether, these results provide the first evidence for a potential neural substrate of the observed impairments in emotion recognition in adults with ADHD.

Keywords: ADHD; Emotion recognition; Middle temporal gyrus; Superior temporal gyrus; Thalamus; fMRI.