Memory Processes in Classification Learning: An Investigation of Amnesic Performance in Categorization of Dot Patterns and Artistic Styles

Abstract

The role of conscious memory retrieval in category learning was investigated, using amnesic patients and matched control subjects on two classification tasks. Subjects attempted to learn to categorize both dot patterns and the paintings of three Italian Renaissance artists. The amnesic patients were capable of normal classification performance on the dot-pattern stimuli, but were severely impaired at learning to categorize the paintings. On tests of recognition of the classification stimuli, the control subjects were very accurate on the paintings, and only moderately accurate on the dot patterns; the amnesic patients were poorer than the control subjects on both item types, though they were above chance in their recognition of the paintings. These data suggest that amnesic patients are capable of simple, perceptually based category learning, but that richer, more complex stimuli may demand memory retrieval processes that they lack.