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Updated: Jan 24, 2026

Visualization of Cortical Modules in Flattened Mammalian Cortices
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Cortical modulation of pupillary function: systematic review.

Costanza Peinkhofer1,2, Gitte M Knudsen1,3,4, Rita Moretti2,5

  • 1Department of Neurology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.

Peerj
|May 24, 2019
PubMed
Summary
This summary is machine-generated.

Pupillary changes reflect cognitive and emotional states, modulated by both cortical and subcortical brain pathways. This review clarifies the brain regions involved in controlling pupillary responses during these processes.

Keywords:
Brain injuryCognitionEmotionFrontal eye fieldMicro stimulationPupillary light reflexStroke

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Area of Science:

  • Neuroscience
  • Autonomic Nervous System
  • Ophthalmology

Background:

  • The pupillary light reflex, controlled by the autonomic system and subcortical pathways, regulates pupil diameter.
  • Cortical influences on pupillary function during cognitive and emotional processing are not fully understood.
  • Understanding these cortical circuits is crucial for interpreting pupillary changes.

Purpose of the Study:

  • To systematically review mechanisms of pupillary changes linked to cognitive efforts and emotion processing.
  • To identify cerebral areas involved in the cortical modulation of the pupillary light reflex.

Main Methods:

  • A systematic literature search was conducted across multiple databases until November 2018.
  • Studies involving humans and non-human primates on cortical modulation of pupillary function were included.
  • 258 out of 8,809 screened papers were selected for review.

Main Results:

  • Pupillary diameter changes (dilatation/constriction) are used as indicators of cognitive and emotional processing, reflecting attention and arousal levels.
  • Cortical activation and lesion models implicated specific brain regions.
  • Key areas include the insular cortex (BAs 13, 16), frontal eye field (BA 8), prefrontal cortex (BAs 11, 25), locus coeruleus, and superior colliculus.

Conclusions:

  • Pupillary dilatation is associated with mental/emotional processes via sympathetic activation or parasympathetic inhibition.
  • Pupillary constriction can occur with anticipated light stimuli, relying on parasympathetic activation.
  • Both pupillary responses are governed by interconnected subcortical and cortical structures linked to brainstem pupillary control.