Pupillometry and P3 index the locus coeruleus–noradrenergic arousal function in humans

• DOI: 10.1111/j.1469-8986.2011.01226.x
• Publication Date: 2011-07-18T10:30:49Z
• Authors: Peter R. Murphy; Ian H. Robertson; Joshua H. Balsters; Redmond G. O'connell
• Keywords: Pupillometry; Locus coeruleus; Pupil diameter; Pupillary response; Pupil size; Oddball paradigm

Abstract The adaptive gain theory highlights the pivotal role of locus coeruleus–noradrenergic (LC‐NE) system in regulating task engagement. In humans, however, LC‐NE functional dynamics remain largely unknown. We evaluated utility two candidate psychophysiological markers activity: P3 event‐related potential and pupil diameter. Electroencephalogram pupillometry data were collected from 24 participants who performed a 37‐min auditory oddball task. As predicted by theory, prestimulus diameter exhibited an inverted U‐shaped relationship to performance such that largest amplitudes optimal occurred at same intermediate level Large phasic dilations, contrast, elicited during periods poor followed reengagement increased amplitudes. These results support recent proposals are sensitive mode.