Interaction of tonic neck and vestibular reflexes in the forelimb of the decerebrate cat.

Tonic neck reflexes, studied with EMG recording, have similar dynamics in forelimb extensor muscles of acutely labyrinthectomized cats, and in cats with intact labyrinths. The reflex occurs more frequently in the latter and its gain is higher. In intact preparations we evoked vestibular and tonic neck reflexes separately or in combination, at frequencies of 0.05-0.5 Hz. As expected from earlier work, the two reflexes oppose each other and frequently cancel; the two reflexes add linearly.