Cerebellar cortex and eyeblink conditioning: a reexamination.

C H Yeo; M J Hardiman

doi:10.1007/bf00228191

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Cerebellar cortex and eyeblink conditioning: a reexamination.

C H Yeo·M J Hardiman

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Abstract

We examined the effects of cerebellar cortical lesions upon conditioned nictitating membrane responses in rabbits. Using extended postoperative conditioning and unpaired presentations of the conditioned stimuli (CSs), we confirmed that combined lesions of lobules HVI and ansiform lobe abolished conditioned responses (CRs) established to light and white noise CSs. Extended retraining enabled some slight recovery of CR frequencies. Less extensive cortical lesions produced initial abolition of CRs but allowed more complete recoveries. Although CR frequencies and amplitudes were profoundly depressed by cortical lesions, unconditioned response (UR) amplitudes to periorbital electrical stimulation were enhanced. The dissociation of lesion effects upon conditioned and unconditioned responses is consistent with the suggestion that cerebellar cortical mechanisms are important for the learning and execution of eyeblink conditioning.

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Acoustic Stimulation Analysis of Variance Animals Blinking Brain Mapping Cerebellar Cortex Conditioning, Classical Electric Stimulation Extinction, Psychological Female Male Nictitating Membrane Photic Stimulation Rabbits Journal Article Research Support, Non-U.S. Gov't

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C H Yeo, M J Hardiman. 1992. Cerebellar cortex and eyeblink conditioning: a reexamination.. https://doi.org/10.1007/bf00228191

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