Anatomically based measurement of facial expressions in simulated versus hypnotically induced affect

In an attempt to determine whether hypnotically induced affect could be reliably discriminated from simulations, three hypnotically trained female undergraduate subjects were presented with posthypnotic cues to either experience or simulate varying degrees of anxiety and pleasure. Facial expressions generated by subjects in response to these cues were recorded on videotape and coded by means of the Facial Action Coding System (FACS). It was hypothesized that simulated emotional expressions, requiring greater cortical processing, would be marked by longer onset latencies and greater irregularity or fluctuation in muscular contraction than the presumably automatic changes in facial behavior accompanying posthypnotic emotions. Statistical analyses confirmed both expectations. The results were viewed as reflecting support for the validity of posthypnotically cued affect.