RT Journal Article
SR Electronic
T1 Behavioural and neural signatures of perceptual evidence accumulation are modulated by pupil-linked arousal
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 433060
DO 10.1101/433060
A1 Jochem van Kempen
A1 Gerard M. Loughnane
A1 Daniel P. Newman
A1 Simon P. Kelly
A1 Alexander Thiele
A1 Redmond G O’Connell
A1 Mark A. Bellgrove
YR 2018
UL http://biorxiv.org/content/early/2018/10/03/433060.abstract
AB The timing and accuracy of perceptual decision making is exquisitely sensitive to fluctuations in arousal. Although extensive research has highlighted the role of neural evidence accumulation in forming decisions, our understanding of how arousal impacts these processes remains limited. Here we isolated electrophysiological signatures of evidence accumulation alongside signals reflecting target selection, attentional engagement and motor output and examined their modulation as a function of both tonic and phasic arousal, indexed by baseline and task-evoked pupil diameter, respectively. For both pupillometric measures, the relationship with reaction time was best described by a second-order, U-shaped, polynomial. Additionally, the two pupil measures were predictive of a unique set of EEG signatures that together represent multiple information processing steps of perceptual decision-making, including evidence accumulation. Finally, we found that behavioural variability associated with fluctuations in both tonic and phasic arousal was largely mediated by variability in evidence accumulation.