Simon van Gaal

Host: Eus van Someren e.van.someren@nin.knaw.nl Sleep & Cognition

The Guest Speaker:
Simon van Gaal
Conscious Brain Lab
Brain and Cognition Group
Department of Psychology
Faculty of Social and Behavioral Sciences University of Amsterdam

Title: How catecholaminergic neuromodulation and spontaneous fluctuations in arousal shape our perception.

Abstract:

In 1908, Yerkes and Dodson observed that mice exhibited optimal learning speed when they received moderately strong electrical shocks in response to erroneous choices, as compared to weak or strong shocks. Over the following decades, this pioneering work evolved into the formulation of the by now famous Yerkes-Dodson law, stating that task performance is optimal at moderate levels of arousal. Although this law is standard textbook material for all Psychology and Neuroscience students, surprisingly little is known about its overall characteristics, its underlying neural implementation and its relation to conscious perception. In this talk, I will present findings from recent studies in which we pharmacologically enhanced the overall arousal state of human participants (targeting cholinergic and noradrenergic neuromodulation), while we simultaneously measured pupil- linked arousal fluctuations and brain activity using EEG during perceptual task performance. We show that perception is optimal at mid-levels of arousal and impoverished at too low and too high arousal states. We show that this relationship is adaptive, similarly to well- known normalization mechanisms in neuroscience. We further reveal that noradrenergic enhancement through atomoxetine primarily improves perception, and does not affect metacognitive insight. Finally, we observe both similar, unique, and interactive effects of attention and catecholaminergic neuromodulation on perceptual decisions. These findings reveal a biological basis for a previously unknown effects of arousal on perception, and reveal that these effects are specific and different from the more well-known effects of attention on perception.