Modulation of Early Perceptual Processing by Emotional Expression and Acquired Valence of Faces

Modulation of early perceptual processing by emotional expression and the affective valence of faces was explored in an event-related potential (ERP) study. An associative procedure was used where different neutral faces changed to happy, to angry or, in a control condition, stayed the same. Based on these changes in expression, participants had then to identify each neutral face as belonging to a friendly, hostile, or neutral individual. ERP measures revealed modulations at occipital-temporal sites of the P100 and N170 components by both the emotional expression and the valence of the associated neutral faces. The early posterior negativity (EPN) component, however, was only sensitive to emotional expression. These results are consistent with previous findings showing that emotional expression influences face perception since early stages of visual processing and provide new evidence that this influence can also be transferred to neutral faces through associative learning.