[Motor intention potential. Electrophysiologic objectization of a single intended movement]

Autocorrelation of the EEG was used to registrate a potential from the intact human scalp during intended, but not executed movements (dorsalflexion of the right hallux, imaginated in equal time intervals). This "Motor Intention Potential" (MIP) is a possible electrophysiological sign of the otherwise purely introspectively experienced intention of a voluntary movement and the cortex of the frontal lobes is suspected to be its origin. The average maximum amplitude height is 6 microV, and the potential shows a continuous decrease from the frontal to occipital region. The duration of MIP is in the range of seconds. Methodological questions are discussed, and the MIP is differentiated from other event-, movement- and imagination-related potentials. An attempt is made to place the motor intention potential in the context of existing movement theories.