P300 and Long-Term Memory: Latency Predicts Recognition Performance.

Johnson, Ray; Pfefferbaum, Adolf; Kopell, Bert S.

The study-test paradigm was used to investigate memory acquisition processes and the effects of repetition on long-term recognition memory. In this procedure, subjects are presented with a list of words ("targets") to be memorized (Study series). They are later tested for recognition on a word list comprised of the target words mixed randomly with an equal number of new, distractor words (Test series). Both reaction time and the P300 component of the event-related brain potential were used as measures of processing time. During the Study series, large P300s were elicited despite a word category probability of 1.0. When the words from the Study series were divided on the basis of recognition performance, words that were subsequently recognized elicited P300s with shorter latencies than unrecognized words. P300 amplitude to words in the Study series increased with repetition while maintaining a constant latency. During the Test series, P300 latency and reaction time decreased with repetition for both target and distractor words. P300 amplitude to all words increased substantially over Test repetitions with target words eliciting larger P300s than distractor words. Words that were recognized more consistently during the Test series elicited larger and earlier P300s than words that were recognized less consistently. The P300 amplitude and latency results from both the Study and Test series are interpreted as reflecting the increased discriminability of the target words as the memory trace increases in strength.

LONG-term memory; RECOGNITION (Psychology); PSYCHOLOGY; PSYCHOPHYSIOLOGY

Psychophysiology, 1985, Vol 22, Issue 5, p497

0048-5772

Academic Journal

10.1111/j.1469-8986.1985.tb01639.x