Facial expression in pain: A study of candid photographs

A number of investigators have reported that observers can reliably distinguish facial expressions of pain. The purpose of this study was to describe the consistencies which might exist in facial behavior shown during pain. Sixteen candid photographs showing faces of individuals in situations associated with intense, acute pain (e.g., childbirth, various injuries, surgery without anesthesia) were coded using the anatomically-based Facial Action Coding System (FACS) of Ekman and Friesen. A characteristic pain expression—brow lowering with skin drawn in tightly around closed eyes, accompanied by a horizontally-stretched, open mouth, often with deepening of the nasolabial furrow—occurred consistently in this series.During this work the investigator was supported by NIMH Grant No. 5T32MH 14592. The author wishes to thank Paul Ekman for supplying the pain photographs and Paul Ekman and Jerry Boucher for helpful suggestions throughout the course of this research.