Cristospinal reflex in circular walking.

This study comprised 22 normal adults, 12 males and 10 females. Electromyograms of the bilateral gastrocnemius muscle were recorded during circular walking under two conditions: no caloric stimulation and immediately after irrigating the right auditory canal with 20 degrees C water for 20 s with the horizontal semicircular canal maintained in vertical position. With no caloric stimulation, gastrocnemius muscle activity on the right side exceeded that on the left during dextrorotation and vice versa during sinistrorotation. Following irrigation of the right auditory canal, the activity was greater on the left side than on the right during sinistrorotation, but no consistent differences in muscle activity were observed during dextrorotation. Dextrorotation was associated with ataxic gait in all cases. Thus ampullopetal lymphatic flow in the semicircular canal due to circular walking causes increased antigravity muscle tonus of the ipsilateral leg. This gives the ipsilateral leg assistance for supporting body weight which shifts to the inner side of circular walking.