Psychophysiological indices of implicit memory performance

Abstract

Skin conduction responses (SCRs) and event-related brain potentials (ERPs) are shown to be sensitive indicators of a memory trace in both implicit and explicit tests of memory. In several explicit recognition tasks, the amplitude of both ERPs and SCRs was higher for new than for repeated words, regardless of whether the subjects recognized or missed the old words. In implicit tasks in which reaction times and ERPs were recorded concurrently, categorical decisions were faster with studied than with new words, but the magnitude of the repetition effect did not vary with the number of repetitions or with the elapsed time since the last repetition. In contrast, ERPs were sensitive to both variables, suggesting that ERPs may be correlated with the memory strength of a trace. © 1990, The Psychonomic Soceity, Inc.. All rights reserved.