Abstract
The present study examined the effects of predictability and controllability of aversive shocks on cognitive coping strategy using an N1 wave of auditory event-related brain potentials and a high-frequency component (0.2-0.3 Hz; HF) of heart rate variability. Subjects were divided into three groups : a predictable-controllable (P-C) group (n=16), a predictable-uncontrollable (P-UC) group (n=16), and an unpredictable-uncontrollable (UP-UC) group (n=14). For the P-C and P-UC groups, one of two tones served as a relevant tone to aversive shocks and the other as an irrelevant tone, whereas both tones served as irrelevant stimuli for the UP-UC group. Subjective ratings (on a 9-point scale) of arousal and affective valence were obtained for the aversive period. In the aversive situation, the P-C group showed higher N1 amplitudes to relevant and irrelevant tones and higher arousal ratings than did the P-UC and UP-UC groups. On the other hand, the UP-UC group showed lower N1 amplitude to the irrelevant tone and lower arousal ratings than did the P-C and P-UC groups. However, there were no differences between the three groups in terms of HF power. The relationship between cognitive coping strategy reflected by the N1 wave and subjective and cardiovascular responses will be discussed. (Japanese Journal of Physiological Psychology and Psychophysiology, 21 (3) : 205-216, 2003.)
