Neuronal activity in medial geniculate body following single semicircular canal stimulation.

Unit activity of medial geniculate body (MGB) neurons was recorded in curarized guinea pigs following separate thermal stimulation of single separate thermal stimulation of single semicircular canals. The same neurons were also tested with acoustic stimuli (clicks). Convergence on MGB units of inputs arising from several (2-6) canals was observed. Convergence of acoustic and vesticular influences was also demonstrated. After labyrinthine stimulation MGB neurons usually displayed inhibitory responses and, less frequently, activation. Clicks induced brief burst of activity. Our data indicate the existence of a wide vestibular projection in the MGB.