Habituation of P300 from auditory stimuli

Abstract

In a series of three experiments, the habituation effects on the P300 or P3 event-related brain potential (ERP) elicited with a simple auditory stimulus discrimination task were evaluated. In Experiment 1, possible changes in the P3 for the first 15 individual target stimulus trials were investigated. Neither the component amplitude or latency changed across trials when the target probability was 10%, 30%, or 50%. In Experiment 2, a target probability of 20% was employed, with 10 blocks of 20 target trials that were collected continuously. P3 amplitude declined significantly between the 1st and 10th trial blocks, with no decrements in target-detection performance observed. P3 latency tended to increase with repeated presentations. Experiment 3 was similar to Experiment 2, but the pitch of the target stimulus was changed after the 9th trial block. P3 amplitude again declined between the 1st and 9th trial blocks, but it increased significantly on the 10th block when the target stimulus changed, thereby demonstrating dishabituation. A second decrease in amplitude occurred by the 15th trial block. P3 latency tended to increase with repeated presentations but decreased with the stimulus change. The P3 component elicited with an active discrimination task and auditory stimuli does habituate after a sufficient number of trials have been presented. The implications of these results for the theoretical interpretation of the P3 are discussed. © 1989, Psychonomic Society, Inc.. All rights reserved.