In the course of primary care education, we are taught to examine the reactivity of the pupils to light, and the result is binary – they either constrict or do not. Not much attention was given to the size of the pupil, the speed of constriction, or the duration of constriction.
In a paper published in December 2017, the authors concluded that changes in pupil size have been identified as a reliable marker of underlying brain activity and thus can relate to brain-network state changes. This suggests that pupillometry may be used as an index for network state or functional fluctuations.
This is important to you, and to us as clinicians, because by looking at your pupils with technology like video oculography, or pupilometry – in various situations like in the dark, in a lit room, focusing still and moving targets, watching moving scenery, as well as under cognitive stress – gives us insight to how well your brain is functioning, and more importantly how to help it function better. Are you with someone right now? Have them see if your pupils are different sizes. It may mean that YOUR brain could function better than it already is!
“Back to Pupillometry: How Cortical Network State Fluctuations Tracked by Pupil Dynamics Could Explain Neural Signal Variability in Human Cognitive Neuroscience” by Michael Schwalm and Eduardo Jubal