Investigating subtle changes in facial expression to assess acute pain in Japanese macaques.

ABSTRACT: Changes in facial expression provide cues for assessing emotional states in mammals and may provide non-verbal signals of pain. This study uses geometric morphometrics (GMM) to explore the facial shape variation in female Japanese macaques who underwent experimental laparotomy. Face image samples were collected from video footage of fourteen macaques before surgery and 1, 3, and 7 days after the procedure. Image samples in the pre-surgical condition were considered pain-free, and facial expressions emerging after surgery were investigated as potential indicators of pain. Landmarks for shape analysis were selected based on the underlying facial musculature and their corresponding facial action units and then annotated in 324 pre-surgical and 750 post-surgical images. The expression of pain

SUBMITTER: Gris VN 

PROVIDER: S-EPMC9669003 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature