Experimental studies on therapeutic effect of electrical stimulation of the brain on muscular hypertonus

Possible effective sites in the central nervous system for therapeutic electrical stimulation in muscular hypertonus are presented. The tonic vibration reflex (TVR) was used as a suitable model of a hypertonic muscular mechanism. Using cats, vibration of 225 Hz was applied to the tendon of the gastrocnemius and soleus muscles. During TVR, stimuli of 200 Hz were applied at various sites within the brain. Results showed that stimulation of the contralateral precruciate cortex, the medial part of the internal capsule, the ventralis anterior nucleus of the thalamus, and the ipsilateral anterior lobe of the cerebellum produced an intense inhibitory effect on TVR, but no significant effect by stimulation alone. Therefore, it is suggested that stimulation of these structures should be suitable for clinical application.