Functional neuroimaging studies of attention-deficit/hyperactivity disorder (ADHD) have focused on the neural correlates of cognitive control. However, for many youths with ADHD, emotional lability is an important clinical feature of the disorder. We aimed to identify the neural substrates associated with emotional lability that were distinct from impairments in cognitive control and to assess the effects that stimulants have on those substrates. We used functional magnetic resonance imaging (fMRI) to assess neural activity in adolescents with (N=15) and without (N=15) ADHD while they performed cognitive and emotional versions of the Stroop task that engage cognitive control and emotional processing, respectively. The participants with ADHD were scanned both on and off stimulant medication in a counterbalanced fashion. Controlling for differences in cognitive control, we found that during the emotional Stroop task, adolescents with ADHD as compared with controls demonstrated atypical activity in the medial prefrontal cortex (mPFC). Stimulants attenuated activity in the mPFC to levels comparable with controls.
Bibliographical noteFunding Information:
This work was supported by the American Academy of Child and Adolescent Psychiatry (Posner), the Klingenstein Third Generation Foundation (Posner and Maia), K23 MH091249 (Posner), the United Negro College Foundation (UNCF)/Merck Postdoctoral Science Research Fellowship (Fair), K08 NS52147 (Nagel), P60 AA010760 pilot funds (Nagel). The authors thank Troy Lubianski for technical assistance.
- Cognitive control
- Emotional lability
- Medial prefrontal cortex