Neural Signals Associated with Orienting Response and Arousal Inhibition in Concealed Information Test.

Recent theory suggests that both the orienting response and arousal inhibition play roles in the effect of the concealed information test (CIT). However, the neural signatures associated with these two processes remain unclear. To address this issue, participants were motivated to either conceal or reveal crime-related stimulus during CIT while EEG was recorded. By using a temporal principal component analysis, we found that crime-related stimuli produced a larger early P3 than crime-irrelevant stimuli in both the conceal condition and reveal condition. This result suggests that this early P3 reflects an orienting response. In addition, we found that crime-related stimuli elicited a larger frontal negative slow wave than crime-irrelevant stimuli in the conceal condition but not the reveal condition, which suggests that the frontal negative slow wave reflects the arousal inhibition process. These results provide crucial evidence for understanding the neural basis underlying CIT.