Cortical modulation of pupillary function: Systematic review
- Published
- Accepted
- Subject Areas
- Anatomy and Physiology, Neurology, Ophthalmology
- Keywords
- emotion, cognition, brain injury, frontal eye field, pupillary light reflex, stroke, micro stimulation
- Copyright
- © 2019 Peinkhofer et al.
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
- Cite this article
- 2019. Cortical modulation of pupillary function: Systematic review. PeerJ Preprints 7:e27510v1 https://doi.org/10.7287/peerj.preprints.27510v1
Abstract
Background. The pupillary light reflex is the main mechanism that regulates the pupillary diameter; it is controlled by the autonomic system and mediated by subcortical pathways. In addition, cognitive and emotional processes influence pupillary function due to input from cortical innervation, but the exact circuits remain poorly understood. We performed a systematic review to evaluate the mechanisms behind pupillary changes associated with cognitive efforts and processing of emotions and to investigate the cerebral areas involved in cortical modulation of the pupillary light reflex.
Methodology. We searched multiple databases until November 2018 for studies on cortical modulation of pupillary function in humans and non-human primates. Of 8808 papers screened, 252 studies were included.
Results. Most investigators focused on pupillary dilatation as an index of cognitive and emotional processing, evaluating how changes in pupillary diameter reflect levels of attention and arousal. Only few tried to correlate specific cerebral areas to pupillary changes, using either cortical activation models (employing micro-stimulation of cortical structures in non-human primates) or cortical lesion models (e.g. investigating patients with stroke and damage to salient cortical and/or subcortical areas). Results suggest involvement of several cortical regions, including the insular cortex, the frontal eye field and the prefrontal cortex, and of subcortical structures such as the locus coeruleus and the superior colliculus.
Conclusions. Pupillary dilatation occurs with many kinds of mental or emotional processes, following sympathetic activation or parasympathetic inhibition. This phenomenon is controlled by several subcortical and cortical structures that are directly or indirectly connected to the brainstem pupillary innervation system.
Author Comment
We understand the PeerJ Preprints policy and wish to proceed with publishing our work as a preprint