THE INFLUENCES OF ELECTRICAL STIMULATION OF BAT CEREBELLUM ON ACOUSTIC RESPONSES OF SUPERIOR COLLICULAR NEURONS
电刺激蝙蝠小脑对中脑上丘神经元听反应的影响

The influences of electrical stimulation of cerebellum on acoustically evoked responses of superiorcollicular SC) neurons were studied in 23 barbitarate-anesthetized bats, Myotis chinensis.Among 7] SC neurons observed, 116 neurons (67. 84%) were affected by cerebellum stimulation. Responses of 72 (42.11%) SC neurons were inhibited and 44 (25.73%) SC neurons were facilitated. The proportion of SC neurons affected by electrical stimulation of vermis was smaller than that of SC neurons affected by electrical stimulation of hemisphere or palaflocculus. The influence of cerebellum on auditory response of SC neurons was bilateral.The inhibitory and facilitatory degrees were dependent on the amplitude of both acoustic and electrical stimuli. Inhibition of SC neurons activity was also dependent on the the interval between the two stimuli. The best inhibitory latencies ranged from 4 to 28ms, and the mojority varied from 6 to 20ms. It is assumed that the influences of cerebellum on SC neurons are a part of the mechanisms of cerebellum to controll acoustic-motion during bat echolocating.