Infants' emotional expression: Differences in the expression of pleasure and discomfort between infants from Chile and the United States

Nonverbal cues have been fundamental to the survival of our species, and they remain a critical aspect of communication. Starting at the moment of birth, children's facial expressions and body gestures reflecting pleasure and discomfort elicit different responses from caregivers, which can shape the trajectory of child development. Although early expressions of emotion are universal, socialization of the intensity of expressions begins in infancy and may be influenced by the place the child is born, family characteristics, and other factors. The aim of this study is to describe the differences in the intensity of emotional expression between Chilean and U.S. infants at approximately 1 year of age. Infants' emotional expressions of pleasure and discomfort are described in terms of total intensity and specific facial and corporal intensities. The expressions were assessed by videotaping and coding the children's behaviours during a sequence of pleasurable and displeasing activities. The analyses revealed that the U.S. children expressed pleasure and discomfort with greater intensity compared with the Chilean children, specifically through corporal expressions. Highlights This study explores differences in the intensity of emotional expression of Chilean and U.S. infants around 1 year of age. Assessment involved a sequence of videotaped tasks and showed U.S. infants expressed pleasure and discomfort with higher intensity than Chilean infants. Differences between both samples at 1 year reveal the possibility that cultural emotion socialization shapes emotional expressions very early in development.