Abstract
While investigating the timing of the N180 wave of human VEPs, we found earlier that correct recognition of facial emotions was characterised by the primary activation of the right fronto-central regions followed by the immediate involvement of the left ones.
The aim of the present study was to analyse the relations between the parameters of the N400 wave, its regional and hemispheric specificity, and the accuracy of emotion recognition. Twenty healthy right-handed subjects and thirty-two untreated psychiatric patients with mild cognitive dysfunction were instructed to recognise the emotional expression of sad, neutral, or laughing faces presented for 80 ms on a computer screen. The amplitude and peak latency of the N400 response were found to be closely related to the accuracy of recognition. In healthy subjects the main difference between error and correct recognition manifested itself in decreased amplitude and shortened latency of the N400 response in frontal and central zones of the left hemisphere (p<0.001). Compared to healthy subjects, the patients demonstrated both poor recognition and decreased latency and amplitude of the N400 response in the left frontal regions (p<0.0001). The results suggest that activation of the left fronto-central regions plays a principal role in the final stages of facial emotion identification.
Get full access to this article
View all access options for this article.