Pupil Size as a Window on Neural Substrates of Cognition

Recent years have seen a surge in interest in using pupil size to gain insights into how the brain processes information in the context of a broad range of behavioral tasks; for example, a search for ‘pupil’ and ‘behavior’ returned a list of around three studies/year from 1967 to 2008 and >15 studies/year from 2009 to 2019. A growing body of anatomical and functional work has identified key roles for three brain regions in funneling cognitively...