Olfactory stimuli as a modulating fator of emotional expression and recognition

Abstract

The recognition of emotions based on facial expressions is a process that involves the integration of context information and can be influenced by emotional reactions. Body posture and surrounding visual scenes, for example, can generate emotions that may interfere in the identification of the emotion demonstrated in the facial expression. The olfactory system can initiate changes in the peripheral nervous system, and its neuroanatomy is intertwined with brain areas responsible for emotional processing. Research in this area demonstrated that olfactory stimulus can influence the recognition of facial expressions, especially of low-intensity expressions (subtle emotional reaction). Pleasant odors can facilitate the identification of happiness expressions and inhibit the recognition of aversive expressions, and the unpleasant ones presented the opposite reaction. One hypothesis developed by the researchers is that this influence occurs because of a facial feedback process. The reactions of the facial musculature, in response to the olfactory stimulation, interfere in the identification of the expressions. The objective of the present study is to evaluate the performance and peripheral activity (skin conductance responses, heart frequency and the activity of the muscles corrugator and zygomaticus major) of the sample in a facial expressions recognition task under olfactory stimulation. Three odor contexts and a control condition (no odor) will be presented during the experiment, to analyze the performance and peripheral nervous system activity in each context. (AU)