Neurophysiological markers that predict and track treatment outcomes in childhood anxiety.

The present study examined the cortical processes that mediate cognitive regulation in response to emotion-eliciting stimuli, before and after anxious children participated in a cognitive behavioral therapy program. Electroencephalographic activity was recorded from anxious children (n = 24, 8 males) and comparison children (n = 16, 7 males) at pre-and post-treatment sessions. The change in anxiety T-scores from pre- to post-treatment was used to signify clinical improvement among anxious children (Improvers: n = 11 vs. Non-improvers: n = 13). Event-related potential components were recorded while children performed a Go/No-go task using emotional facial expressions. For the P1 component, believed to reflect attention and/or arousal processes, Non-improvers had greater activation levels relative to Improver and comparison groups at both sessions. Greater P1 amplitudes at pre-treatment predicted non-improvement following treatment. For the frontal N2 component, thought to reflect cognitive control processing, Improvers recruited greater activation from pre- to post-treatment, a change in activation that was predictive of treatment outcome. Non-improvers showed increased cortical activation within the time window of the P1, whether at pre- or post-treatment. These data suggest that heightened perceptual vigilance may have led to poorer outcomes. Improvers showed increased prefrontal activation within the time window of the N2 from pre- to post-treatment. These data suggest that increased cognitive control may have led to improved treatment outcomes. In sum, P1 activation may serve as a predictor of treatment outcome, while N2 activation may serve as an indicator of treatment response.