| Abstract: | H.M., a well-known S with bilateral removal of medial-temporal-lobe structures and profound amnesia, performed eyeblink classical conditioning (EBCC) for 21 90-trial sessions in the 400-msec delay and 900-msec trace paradigms. A 2nd amnesic S with temporal lobe lesions and 2 normal control Ss (NCSs) were also conditioned. Acquisition occurred in both paradigms for all Ss. Acquisition in the delay paradigm was prolonged in H.M. (perhaps because of his cerebellar degeneration in the vermis and hemispheres), but not in the 2nd amnesic S. Amnesic Ss and NCSs showed more rapid acquisition in the trace than in the delay paradigm. Two years after initial EBCC, H.M. attained learning criterion in the trace paradigm in 1/10th as many trials. No recollection of the experimenters, apparatus, instructions, or procedure was manifested by H.M. Results suggest that humans can condition in the 400-msec delay and 900-msec trace EBCC paradigms with the hippocampus radically excised. (PsycINFO Database Record (c) 2010 APA, all rights reserved) |
