Preserved learning and memory in amnesia: intact adaptation-level effects and learning of stereoscopic depth

Abstract

Amnesic patients and control Ss performed similarly on 2 memory tests. In Experiments 1A and 1B, amnesic patients exhibited intact adaptation-level effects: An experience lifting and judging a group of weights influenced their judgments of a 2nd group of weights 20-25 min later. The effect did not depend on peripheral accommodation, because Ss used 1 hand during their 1st encounter with the weights and the opposite hand during their 2nd encounter. In Experiment 2, amnesic patients acquired at a normal rate the ability to perceive binocular depth using random-dot stereograms. In both experiments, amnesic patients benefited from recent experience, despite the fact that they could not remember their prior experience accurately. The preserved memory abilities demonstrated here appear to be examples of implicit, or nondeclarative, memory.