RESUMO
Results of comparison of power of EMG of six pericranial muscles in electroencephalographic frequency ranges beta1, beta2 and gamma are presented corresponding to performances of the tasks bound to inductions of affective experiences-external by means of presentation of images and internal by means of autobiographical memoirs revived. The tasks were focused on an induction of affective experiences with different emotional valencies--positive, negative and neutral. The EMG was derived, registered and processed by means of a computer electroencephalography techniques. Self-ratings of signs and intensities of tested emotions were recorded as well. The study involved two groups of healthy subjects--students-actors (N = 39), and students of other majors (N = 32). Statistically reliable, reproducible and diverse differences of averaged EMG power of the pericranial muscles took place as in comparisons of psychophysiological conditions with different valencies of emotions, as well in comparisons of conditions without expressed emotional differences, but differing in the direction of attention. Therefore it is obviously necessary for an assessment of a degree of muscular contamination in records of high-frequency scalp EEG to supplement psychophysiological EEG methods with EMG registration and statistical analysis and to do such registration for several facial muscles.
