Automated rhythmic movements and their control under different experimental conditions.

Automated rhythmic movements (tapping) represent a facility for the examination of a motor control subsystem. The actual tapping frequency is influenced by variations of experimental conditions and related to EEG phenomena. The study deals with the effect of different instructions and additional mental load upon tapping and its relation to EEG rhythms. Depending on instruction, large differences occur between "maximum" and "convenient" rhythm, the latter being much slower. If maximum speed is required, the sub ect produces a higher frequency by its dominant hand; there is no difference between tapping without additional load (non-dominant hand) and with additional load (dominant hand). Previous results concerning the relationship between EEG rhythms and tapping movements could be confirmed.