Nontechnical Abstract Measuring Emotion in Chimpanzees Using Cognitive Tasks This project aims to establish a new, pioneering direction of research to measure the subjective experience of emotion in chimpanzees, the closest living relative of humans. The technique combines experimental and physiological techniques to provide an objective measure of emotional responses in a nonverbal animal. Changes in psychophysiological responses, such as changes in electronic conduction of facial muscles and skin will be measured when subjects view emotion-eliciting videos, and when required to categorize these videos according to their emotional valence. Categorization involves matching positive, negative and neutral facial expressions with videos of social scenes presented on a computer monitor by contacting them with a joystick-controlled cursor. Traditionally, students of nonhuman primates have investigated social behavior and social cognition while ignoring the emotional aspects. Emotion is considered inaccessible in a nonverbal species. Psychophysiological responses, such as those noted above, have an inherent correlation with autonomic nervous system functions that have been associated with the experience of emotion in humans. Measuring psychophysiological parameters in nonverbal organisms will provide an objective measure of what are often covert, unconscious responses. Applying an objective, empirical measure of emotion to chimpanzees will broaden an understanding of the evolution of emotional responses and empathy in humans.
