ERPs (event-related potentials), semantic attribution, and facial expression of emotions

ERPs (event-related potentials) correlates are largely used in cognitive psychology and specifically for analysis of semantic information processing. Previous research has underlined a strong correlation between a negative-ongoing wave (N400), more frontally distributed, and semantic linguistic or extra-linguistic anomalies. With reference to the extra-linguistic domain, our experiment analyzed ERP variation in a semantic task of comprehension of emotional facial expressions. The experiment explored the effect of expectancy violation when subjects observed congruous or incongruous emotional facial patterns. Four prototypical (anger, sadness, happiness and surprise) and four morphed faces were presented. Moreover, two distinct cognitive tasks (an implicit vs an explicit elaboration) were analyzed in order to evaluate the influence of spontaneous decoding in N400-like effects. An automatic, high-order cognitive process was found, elicited by a negative ERP variation similar to the linguistic N400 effect, which allows us to explain the congruous/incongruous decoding in semantic extra-linguistic comprehension.