Informations and abstract
The present research aims to explore the presence of a cognitive process for emotional face recognition by means of ERP correlates (event-related potentials). In the Experiment 1 (supraliminal condition) twenty subjects saw five emotional facial expressions (anger, fear, joy, surprise, and sadness) and a neutral face (baseline). Emotional decoding produced a negative ongoing deflection at about 230 ms (temporal window 180-300) post-stimulus (N2 effect), subsequent to N1 ERP variation, more distributed in the posterior area (Pz). This effect may represent a "facial-emotion-specific" index, clearly differentiated from the "structural index", elicited by N1 correlate. Moreover, an emotion-specificity response was observed as a function of the evaluation of each expression, in terms of both the hedonic valence and the arousal of the stimulus. In addition, a cortical asimmetry was revealed for the negative emotions (anger, fear and sadness), more rightly distributed than the positive ones. In the Experiment 2 (twenty subjects) a subliminal stimulation was carried out (10 ms), preventing a conscious elaboration of the emotional face, in order to analyze its effect on the cognitive processes underlying. A morphological similarity was observed between supraliminal and subliminal conditions, even if N2 was temporally delayed in the last one (about 240 ms). It is hypothesizable a partial similarity of the cognitive processes underlying supraliminal and subliminal elaboration, even if temporally differentiated as a function of the experimental condition.