Abstract
<title>Abstract</title> <p>Pupillary and electroencephalographic (EEG) signals can reflect arousal-related responses to violations of temporal auditory regularities, involving locus coeruleus-noradrenergic (LC-NE) system neuromodulation. We combined simultaneous pupillometry and EEG with a local-global auditory paradigm in 26 adults to test whether pupil and event-related potentials (ERPs) show comparable sensitivity to attentional demands. Participants completed active counting and visual interference tasks. During counting, deviants elicited significant pupil dilation for local (44-1232 ms, p = .0031; Δ = .09 z) and global violations (288–2000 ms, p = .0001; Δ = .45), with ERP effects at Pz (local: 2.51 µV; global: 2.01 µV). Under visual interference, pupil effects were reduced but remained significant for local (0-690 ms, p = .0247; Δ = .05) and global violations (446–1818 ms, p = .0083; Δ = .11), whereas ERP effects were mostly absent. These findings suggest that pupil responses remain sensitive to auditory deviance when ERP effects are attenuated.</p>