Task-specific EMG-characteristics during mental training

Despite a sixty-year tradition of research into ideomotor reaction it is not yet clear, whether myoelectric activity measured during mental training contains only inner-organismic or in addition task-specific information.Our investigation involved one group trained actively in a sensorimotor task (paced contour-tracking), another group which was intermediately instructed to train on a mental level, and a third (control) group which had no instruction for training in the intermediate performances. Measurements were taken of the muscular activity (EMG) of the main working muscle (m. biceps) synchronously to the motion of the target in all three groups.The data were submitted to several time series analysis procedures: auto-correlative measures and power spectra. Correlations were found between the filtered time series of the track and the EMG-activity in the mental training performances. The frequency distribution in the power spectra of the track was found in the power spectra of the active as well as in the mental training groups but not in those of the controls. The results indicate that the myoactivity during mental training clearly shows a task-specific frequency distribution.