Is facial EMG a valid measure?
Facial Electromyography (or fEMG) is a precise and sensitive method to measure emotional expression. Unlike self reports, fEMG does not depend upon language and does not require cognitive effort or memory. fEMG is capable of registering the response even when subjects were instructed to inhibit their emotional expression. It is also able to measure facial muscle activities to even weakly evocative emotional stimuli.
