Neural correlates of task-related refixation behavior

Research output: Contribution to journalArticle

Abstract

Eye movement research has shown that attention shifts from the currently fixated location to the next before a saccade is executed. We investigated whether the cost of the attention shift depends on higher-order processing at the time of fixation, in particular on visual working memory load differences between fixations and refixations on task-relevant items. The attention shift is reflected in EEG activity in the saccade-related potential (SRP). In a free viewing task involving visual search and memorization of multiple targets amongst distractors, we compared the SRP in first fixations versus refixations on targets and distractors. The task-relevance of targets implies that more information will be loaded in memory (e.g. both identity and location) than for distractors (e.g. location only). First fixations will involve greater memory load than refixations, since first fixations involve loading of new items, while refixations involve rehearsal of previously visited items. The SRP in the interval preceding the saccade away from a target or distractor revealed that saccade preparation is affected by task-relevance and refixation behavior. For task-relevant items only, we found longer fixation duration and higher SRP amplitudes for first fixations than for refixations over the occipital region and the opposite effect over the frontal region. Our findings provide first neurophysiological evidence that working memory loading of task-relevant information at fixation affects saccade planning.

Details

Authors
Organisations
External organisations
  • Catholic University of Leuven
  • Technical University Of Kaiserslautern
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Psychology

Keywords

  • EEG, Free viewing, Saccade planning, Task relevance, Visual search
Original languageEnglish
Pages (from-to)90-101
Number of pages12
JournalVision Research
Volume175
Publication statusPublished - 2020 Oct 1
Publication categoryResearch
Peer-reviewedYes