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Abstract:
Abstract: The ability to inhibit a prepotent response
improves with development and is typically difficult for children
with ADHD. We recorded event-related brain potentials (ERPs) in
children between 8 and 13 years of age while they performed a
visual Go/No-Go task and a visual oddball task. Stimuli consisted
of four colored shapes. During the Go condition, only target
stimuli were presented. In the subsequent No-Go condition, target
stimuli were intermixed with the non-target (p = 50%), requiring
inhibition of a prepotent response. In the oddball task, the target
stimulus (p = 25%) was the non-target shape from the Go/No-Go task.
Reaction times to targets were significantly faster in the Go
condition than the No-Go condition. False alarm rate was positively
correlated with target reaction time in the No-Go condition. Target
responses in both tasks evoked a P3b complex as well as a late
frontal positivity. Independent Component Analysis (ICA), a method
for blind source separation, was performed on the grand average ERP
responses. The target P3b complex was decomposed into 3 spatially
fixed, temporally independent components. One of these components
differed in the No-Go condition and the oddball task, perhaps
reflective of increased inhibition of a prepotent response. The
late frontal positive component was associated with differences in
target probability across conditions.
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