[Wavelet transformation of event-related cortical activity during formation of visual set to emotional face image]

A cognitive set to emotional facial expression was formed in 35 young adults. Rhythmical components of the event-related activity within short time intervals were revealed using wavelet functions. Maximum and mean levels of wavelet coefficient (WLC) were analyzed in the alpha-and theta-bands. In subjects with the rigid cognitive set, the WLC maxima in the alpha-band were higher than that in subjects with the plastic set. The mean level of the theta-oscillations in subjects without set manifestations (plastic set) was higher than in subjects who displayed erroneous responses (rigid set). At different stages of the experiment, different values of the maximum and mean levels were observed in the studied frequency bands. We think that set formation (and extinction) is associated in different groups of subjects with different cortico-subcortical relations at different stages of the set.