Familiarity effects on facial emotion processing: an ERP study

• Autor(a) principal: Ana Luisa Pereira Abreu
• Data de Publicação: 2022
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: https://hdl.handle.net/10216/141667
• topic: Psicologia; Psychology

From the time we are born faces might surely be the most pertinent social stimuli, with a role in identifying emotions and identity, vital processes that monitor our daily interactions. Previous research suggests that face recognition is enhanced by their degree of familiarity. Thus, the present study aims to explore how familiarity improves face processing. We hypothesize that the neural response and accuracy rates will be higher with the increase of familiarity of each face. This can be explained by the greater robustness of the neural representations for these stimuli that can induce extra neural processes to the ones already prompted by facial identification (e.g., affective processes and autobiographical information related to the individual recognized). Through two experimental tasks, we analysed accuracy rates and the morphology of event-related brain potentials associated with face processing (P100, N170, and N250), elicited by inverted and emotional faces with different degrees of familiarity. In the first task, to study facial processing, three different categories of facial stimuli were presented during a target detection task: famous familiar faces; personally familiar faces; and unfamiliar faces. To explore the face inversion effect accordingly to each degree of familiarity, these facial stimuli were also presented upside down. In the second task, to study emotional face processing, an emotional recognition task on personally familiar and unfamiliar faces was conducted. The behavioural results showed an improved performance in the identification of facial expressions of emotion with the increase of facial familiarity, consistent with the previous literature. The electrophysiological results showed an enhanced response exclusive to N250 when personally familiar faces were presented in comparison to unfamiliar faces. The higher recruitment of neural resources for familiar faces was expected in relation to the further information elicited by our loved ones faces. Finally, a higher response of the three components when faces were presented upside down, independently of their degree of familiarity, was obtained. This result is in line with previous research suggesting that inverted faces are more difficult to process, leading to higher recruitment of neural resources.