Attention-dependent sound offset-related brain potentials

Horváth, János (2016) Attention-dependent sound offset-related brain potentials. Psychophysiology, 53 (5). pp. 663-677. ISSN 00485772

Preview

Text horvath_j2016psychophysiology53_663_am.pdf - Accepted Version Available under License Creative Commons Attribution Non-commercial No Derivatives. Download (2MB) | Preview

Abstract

When performing sensory tasks, knowing the potentially occurring goal-relevant and -irrelevant stimulus events allows the establishment of selective attention sets, which result in enhanced sensory processing of goal-relevant events. In the auditory modality, such enhancements are reflected in the increased amplitude of the N1 event-related potential (ERP) elicited by the onsets of task-relevant sounds. It has been recently suggested that ERPs to task-relevant sound offsets are similarly enhanced in a tone-focused state in comparison to a distracted one. The goal of the present study was to explore the influence of attention on ERPs elicited by sound offsets. ERPs elicited by tones in a duration-discrimination task were compared to ERPs elicited by the same tones in not-tone-focused attentional setting. Tone offsets elicited a consistent, attention-dependent bi-phasic (positive-negative – P1-N1) ERP waveform for tone durations ranging from 150 to 450 ms. The evidence, however, did not support the notion that the offset-related ERPs reflected an offset-specific attention set: The offset-related ERPs elicited in a duration-discrimination condition (in which offsets were task-relevant) did not significantly differ from those elicited in a pitch-discrimination condition (in which the offsets were task-irrelevant). Although an N2 reflecting the processing of offsets in task-related terms contributed to the observed waveform, this contribution was separable from the offset-related P1 and N1. The results demonstrate that when tones are attended, offset-related ERPs may substantially overlap endogenous ERP activity in the post-offset interval irrespective of tone duration; and attention differences may cause ERP differences in such post-offset intervals.

Actions (login required)

Edit Item