CLASSICAL-CONDITIONING AFTER CEREBELLAR LESIONS IN HUMANS

We explored classical conditioning in human subjects who had lesions i n their cerebellar circuitry. Seven patients with damage to cerebellar structures and matched control subjects underwent simple delay tone-a irpuff conditioning. Eyelid conditioned response (CR) acquisition was severely disrupted in the patient group, whereas autonomic CRs and slo w cortical potentials developing between conditioned stimulus (CS) and the unconditioned stimulus (UCS) were unaffected. Results are consist ent with animal studies and earlier case reports indicating that intac t cerebellar structures are necessary for the acquisition of classical ly conditioned motor responses.