[Identification of possible cognizance parameters of "mimic disintegration" in schizophrenia using facial electromyography].

UNLABELLED: The aim of this study was to identify signs of "mimic disintegration" in schizophrenics using a facial electromyographic (EMG) method. We compared a group of 20 unmedicated schizophrenics with a group of 20 healthy subjects, measuring the activity of three joy-relevant facial muscles (zygomaticus major, orbicularis oculi, levator labii superioris) and two nonjoy-relevant facial muscles (frontalis, corrugator supercilii) as control muscles during two consecutive presentations of an erotic slide from the International Affective Picture System. RESULT: Schizophrenics show significantly less activity of joy-relevant facial muscles and a lower smile frequency than healthy subjects. Two signs of mimic disintegration" could be identified: 1. undefined mimic reactions and 2. lack of mimic consistency.
CONCLUSION: Facial EMG is a state-of-the-art method for analyzing possible signs of mimic disintegration as described by Heimann and Spoerri. We suggest further examination of the two mimic disintegration signs regarding other emotions, necessarily including more facial muscles in the testing.