The pupillary respiratory-phase response: pupil size is smallest around inhalation onset and largest during exhalation.

ABSTRACT: Respiration shapes brain activity and synchronizes sensory and exploratory motor actions, with some evidence suggesting that it also affects pupil size. However, evidence for a coupling between respiration and pupil size remains scarce and inconclusive, hindered by small sample sizes and limited controls. Given the importance of pupil size in visual perception and as a reflection of brain state, understanding its relationship with respiration is essential. In five experiments using a pre-registered protocol, we systematically investigated how respiratory phase affects pupil size across different conditions. In Experiment 1 (n = 50), we examined nasal and oral breathing at rest under dim lighting with nearby fixation points, then replicated these results under identical conditions in Experi

SUBMITTER: Schaefer M 

PROVIDER: S-EPMC11908488 | biostudies-literature | 2025 Mar

REPOSITORIES: biostudies-literature