Both a gauge and a filter: Cognitive modulations of pupil size

R. Becket Ebitz, Tirin Moore

Research output: Contribution to journalReview articlepeer-review

22 Scopus citations


Over 50 years of research have established that cognitive processes influence pupil size. This has led to the widespread use of pupil size as a peripheral measure of cortical processing in psychology and neuroscience. However, the function of cortical control over the pupil remains poorly understood. Why does visual attention change the pupil light reflex? Why do mental effort and surprise cause pupil dilation? Here, we consider these functional questions as we review and synthesize two literatures on cognitive effects on the pupil: how cognition affects pupil light response and how cognition affects pupil size under constant luminance. We propose that cognition may have co-opted control of the pupil in order to filter incoming visual information to optimize it for particular goals. This could complement other cortical mechanisms through which cognition shapes visual perception.

Original languageEnglish (US)
Article number1190
JournalFrontiers in Neurology
Issue numberJAN
StatePublished - 2019

Bibliographical note

Funding Information:
This work was funded by the National Eye Institute (R01-EY014924 to TM and 5T32-EY020485 to RE) and the National Institute of Mental Health (F32-MH102049).

Publisher Copyright:
Copyright © 2019 Ebitz and Moore. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.


  • Attention
  • Decision-making
  • Exploration
  • Pupil light reflex
  • Pupil light response (PLR)
  • Pupil size
  • Visual perception

PubMed: MeSH publication types

  • Review
  • Journal Article


Dive into the research topics of 'Both a gauge and a filter: Cognitive modulations of pupil size'. Together they form a unique fingerprint.

Cite this