THE EFECTS OF SMILE MUSCLES CONTRACTION ON MOOD AND COGNITION

• Grant number: 15/00590-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2015
• End date: December 31, 2015
• Field of knowledge: Humanities - Psychology - Physiological Psychology
• Principal Investigator: Sabine Pompéia
• Grantee: Amanda Zamparo Franco
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil

Abstract

There are conflicting reports in the literature on cognitive and mood effects induced by manipulations that induce facial muscle contraction similar to a smile. It is unclear whether the identification of facial expressions of others with the use of these manipulations depends on the reduced ability to mimic facial movements to reflect the observed emotions or reflectes changes in mood. This study will involve 40 healthy young men randomly divided into two groups: a facial manipulation that most resembles a real smile and better inhibites facial mimicry of this emotion (holding a pen with the teeth pointing to the sides of the mouth), or a control condition (holding a pen with the non-dominant hand). It will be determined if the first manipulation changes the identification of any of the six types of basic emotions expressed in faces (happiness, sadness, anger, disgust, surprise, fear) in terms of the name of the emotion and its intensity, as well as the mood of the participants and performance in several behavioral control measures that are affected by mood (4 types of executive functions, evaluation of humorous content of jokes and autobiographical memories). The interoceptive accuracy (ability to perceive physiological changes) with heartbeat count will be controlled. We expect to determine whether the cognitive effects of facial muscle contraction similar to a smile reflects mood changes or reduction of facial mimicry, and to what extent these effects are modulated by the ability to perceive bodily changes.