Movement control

Movement control was studied on a number of stabilization tasks related to orientation of the human in space. It was assumed, that the stabilization system is provided with information about deviation from the given orientation delivered by different sensory systems ( vestibular, visual, proprioceptive, auditory ). In the theoretical consideration the main attention was paid for sensory interaction mechanisms ensuring the least stabilization error. It was shown that the stabilization system should contain at least two channels transferred independently information about deviation and its velocity and the velocity channel is much more significant for the whole stabilization system ( V.Gusev, L.Semenov, A model for optimal processing of multisensory information in the system for maintaining body orientation in the human, Biol. Cybern., 1992, 66, p. 407-411 ).

An another important extension of the developed approach was consideration of an additional emerged sensory channel formed by the galvanic stimulation of the vestibular apparatus. The primary source of information for the new channel was the high sensitive accelerometer rigidly attached to the human body, which along with integrative circuits transferred information about deviation from the given orientation. It was experimentally shown, that this signal applied as galvanic stimulation with head skin electrodes uses the vestibular pathway and modifies the sensory interaction. The proposed mathematical model of an extended stabilization system revealed the phenomenon, that the new channel is able to transfer very detailed information and is included in the sensory integration mechanism. Being able to transfer absolutely reliable information about current deviation from the given orientation this channel could diminish the total stabilization error under its natural level. This phenomenon was supported by the experimental studies concerned stabilization task for the human asked to maintain his local vertical in the sensory conflict condition. ( V.Goussev, I.Orlov, S.Dolgobrodov Suppression of the sensory conflict status using biofeedback information channel. Proceedings of the 1998 2-nd International Biomedical Engineering Days, IEEE Catalog # 98TH8327, p. 23-32 ).
Revealed new properties of the galvanic biofeedback makes it promising for different biomedical and technological applications such as correction of gait and posture or suppression of the sensory conflict status.