Geometric morphometrics for the study of facial expression of pain in common marmosets

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K20616
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0605:Veterinary medical science, animal science, and related fields
• Research Institution: Kyoto University
• Principal Investigator: WILSON DUNCAN 京都大学, 文学研究科, 講師 (20828925)
• Project Period (FY): 2021-08-30 – 2024-03-31
• Keywords: geometric morphometrics / facial expression / pain / behaviour / common marmoset

Outline of Final Research Achievements

The aim of this study was to identify facial expressions associated with pain in common marmosets. We used geometric morphometrics (GMM) to evaluate face shape changes after routine laparotomy (abdominal) surgery. The GMM analysis revealed face shape changes potentially associated with postoperative pain, including contraction of the eye and mouth areas and raising of the ear tufts. Recently, similar face shape changes associated with pain have also been identified in Japanese macaques. This study provides further evidence that GMM is a useful tool for assessing pain in non-human primates, which contributes towards the overall goal of improving pain recognition and welfare. The funding for this project supported the publication of two related papers and a third paper is in preparation.

Free Research Field

Laboratory Animal Science

Academic Significance and Societal Importance of the Research Achievements

This study identified face shape changes in common marmosets potentially associated with pain using geometric morphometrics. This contributes towards better pain recognition, which will ultimately lead to improved data reliability and validity in marmoset studies aimed at improving human health.