Individual- and situation-dependent variations in facial expressions of pain and their impact on decoding processes
Final Report Abstract
Perceptually training participants to become aware of different facial activity patterns indicative of pain led to an improved ability to correctly identify facial responses to pain as pain expressions (sensitivity). After having learned which facial actions co-occur with pain in a brief training procedure (20 minutes), participants were better able to identify pain responses amongst disgust and neutral facial expressions. Sensitivity increased from below 70% to more than 80% after the training and this increase could still be found 1 month after completing the training. Thus, this brief training procedure promised to lead to clinically relevant improvements in the ability to identify pain states. However, it did not improve observers’ ability to correctly identify facial responses to disgust and neutral states as nonpainful states (specificity). On the opposite, specificity rates decreased after the training and remained that way even after 1 month after the training. However, from an ethical point of view, it seems more important to identify all those individuals who are suffering from pain and treat their pain even if it means that some individuals might be falsely identified to be suffering from pain. If one monitors the patient and his/her behavior (including the facial expression) across time and across pain treatment attempts, these falsely identified patients will likely be identified as “false positives”. In accordance with previous findings, the knowledge about different facial activity patterns (learned during the training) did not help the participants to correctly infer the pain intensity of the individuals they are observing. Nurses with long-standing experience in pain assessment and pain treatment did not perform better than pain-naïve individuals and profited similarly from the training procedure as the control group did. Thus, experience with pain does not in itself improve the ability to make adequate use of the facial expression to detect and judge pain in others.
Publications
- (2014). The faces of pain: a cluster analysis of individual differences in facial activity patterns of pain. European Journal of Pain, 18(6), 813-823
Kunz, M., & Lautenbacher, S.
(See online at https://doi.org/10.1002/j.1532-2149.2013.00421.x) - (2015). Improving recognition of pain by calling attention to its various faces. European Journal of Pain, vol 19 issue 9, October 2015, Pages 1350-1361
Kunz, M., & Lautenbacher, S.
(See online at https://doi.org/10.1002/ejp.666)
