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Pupil diameter reflects uncertainty in attentional selection during visual search
Joy J Geng1, Zachary Blumenfeld2, Terence L Tyson2
1Center for Mind and Brain and Department of Psychology, University of California, Davis Davis, CA, USA ; Department of Psychology, University of California Davis Davis, CA, USA.
Frontiers in Human Neuroscience
|August 25, 2015
Summary
Pupil diameter changes reflect uncertainty during visual search. This finding suggests pupil size can measure cognitive effort and attentional selection processes.
Area of Science:
- Cognitive Psychology
- Neuroscience
- Ophthalmology
Background:
- Pupil diameter is a traditional indicator of cognitive processing.
- Recent research links pupil size changes to noradrenergic (LC-NE) function and uncertainty processing.
- The role of uncertainty in attentional selection and pupil responses requires further investigation.
Purpose of the Study:
- To investigate the relationship between uncertainty in attentional selection and task-evoked pupil diameter changes during visual search.
- To determine if pupil diameter can serve as an implicit measure of cognitive effort in attentional tasks.
Main Methods:
- Participants performed visual search tasks (Experiments 1-2).
- Task-evoked changes in pupil diameter were measured.
- Reaction time and accuracy were recorded to assess performance and uncertainty.
Main Results:
- Task-evoked pupil diameter changes correlated with uncertainty during attentional selection.
- Performance metrics (reaction time and accuracy) supported the link between pupil response and uncertainty.
- Control analyses ruled out error monitoring and response uncertainty as primary drivers of the observed pupil responses.
Conclusions:
- Pupil diameter serves as a valid implicit metric for quantifying uncertainty in attentional selection.
- The findings highlight the utility of pupil diameter in studying effortful cognitive control processes.
- This research advances our understanding of the neural and cognitive underpinnings of attention and decision-making.
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