Age Related Effects of Emotions on Brain Potentials

Abstract

This experiment will use event-related brain potential (ERP) measures to investigate the time course of emotional expression processing across six emotions (happy, sad, anger, fear, disgust, and neutral) in young and older adults. The experiment had participants perform a gender-discrimination task irrelevant to emotion. At frontocentral electrode locations approximately 160ms post stimulus, younger adults demonstrated a greater positivity for fearful faces as compared to neutral faces. Older adults showed no such effect. When presented with emotional expressions younger adults showed early activation at pre-frontal electrodes followed by activation at more posterior electrode sites. This also contrasted with older adults, who demonstrated persistent pre-frontal activations that began around 160ms and persisted until 800ms. Older adults absence of a positivity elicited by fearful expressions relative to neutral expressions and the presence of an increased pre-frontal activation offers some support for the socio-emotional selectivity theory, which holds that older adults use cognitive emotion processes to regulate emotional stimuli.