Response Decrements in the Cochlear Nucleus of Decerebrate Cats during Repeated Acoustic Stimulation
Gordon L. Humphrey 1 and
Jennifer S. Buchwald 1
1 Departments of Physiology and Psychiatry and Brain Research Institute, University of California Medical Center, Los Angeles 90024
In the cochlear nucleus of decerebrate, paralyzed cats, multiple-unit responses to an acoustic stimulus showed significant decrements when the stimulus was repeatedly presented once every 5 seconds. These decrements developed in the absence of peripheral receptor adaptation. The responses recovered to the level prior to stimulation when stimulation was withheld for 5 to 10 minutes. Dishabituation by somatic stimulation of the forepaw, however, was less effective than in the intact cat. The continued development of response decrements after strychnine blockade of peripheral olivocochlear influences and central postsynaptic inhibition suggests a mechanism of decreased synaptic effectiveness, which has previously been postulated for neuronal habituation in brainstem and spinal cord.
