Abstract
Attention-deficit/hyperactivity disorder (ADHD) is associated with difficulty inhibiting impulsive, hyperactive, and off-task behavior. However, no studies have examined whether a distinct pattern of brain activity precedes inhibitory errors in typically developing (TD) children and children with ADHD. In healthy adults, increased activity in the default mode network, a set of brain regions more active during resting or internally focused states, predicts commission errors, suggesting that momentary lapses of attention are related to inhibitory failures.
Event-related functional magnetic resonance imaging and a go/no-go paradigm were used to explore brain activity preceding errors in 13 children with ADHD and 17 TD controls.
Comparing pre-error with pre-correct trials, TD children showed activation in the precuneus/posterior cingulate cortex and parahippocampal and middle frontal gyri. In contrast, children with ADHD demonstrated activation in the cerebellum, dorsolateral prefrontal cortex (DLPFC), and basal ganglia. Between-group comparison for the pre-error versus pre-correct contrast showed that children with ADHD showed greater activity in the cerebellum, DLPFC, and ventrolateral PFC compared with TD controls. Results of region-of-interest analysis confirmed that the precuneus/posterior cingulate cortex are more active in TD children compared with children with ADHD.
These preliminary data suggest that brain activation patterns immediately preceding errors differ between children with ADHD and TD children. In TD children, momentary lapses of attention precede errors, whereas pre-error activity in children with ADHD may be mediated by different circuits, such as those involved in response selection and control.