Tonal Surprisal and Contextual Shifts Evoke Distinct Pupil Dilation During Dynamic Sound Sequences.

ABSTRACT: The human brain continuously forms predictions about the unfolding sensory environment, relying on contextual information to anticipate upcoming events while remaining sensitive to unexpected changes. This study examined how pupil-linked phasic arousal, a putative proxy for the locus coeruleus-norepinephrine system, reflects the interplay between tonal surprisal (unexpectedness) and precision (reliability of the inferred context) in dynamic auditory contexts. Twenty-eight participants passively listened to stochastic tone sequences transitioning between periods of low-entropy (informative context) and high-entropy (less informative context). We quantified tone-by-tone surprisal and precision using Bayesian modeling. Despite their slow time evolution, pupil dilation responses revealed sensi

SUBMITTER: van Haren JJG 

PROVIDER: S-EPMC12765649 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature