Blue enriched light modulates pupil dilation induced by transcutaneous vagus nerve stimulation.

ABSTRACT: Transcutaneous vagus nerve stimulation (tVNS) targets the auricular branch of the vagus nerve and can modulate brainstem arousal systems, including the locus coeruleus-noradrenaline (LC-NE) pathway. Blue-enriched light also affects LC activity and can enhance alertness and cognition. However, no study has tested whether combining tVNS with blue light could further boost noradrenergic activity in humans. We therefore measured pupil responses, a well-established marker of LC-NE function, to assess how light and tVNS interact. We conducted a randomized, within-subject block design with twenty-five healthy adults (13 men, 12 women, aged 18-34) who received short (3.4 s) bursts of tVNS or sham stimulation (cymba conchae vs. earlobe). Pupil size was recorded under four light conditions: high int

SUBMITTER: Cakiroglu I 

PROVIDER: S-EPMC12847764 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature