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Symposium at BIOMAG 2012 in Paris, France

posted Feb 6, 2012, 1:51 AM by Floris de Lange
The symposium "Cortical network dynamics of perceptual decision-making" has been accepted as a symposium at BIOMAG2012 in Paris, France.

* Tobias Donner, University of Amsterdam, Department of Psychology, Netherlands
* Valentin Wyart, Oxford University, Department of Psychology, United Kingdom
* Saskia Haegens, Columbia University Medical Centre, New York, USA
* Floris de Lange, Radboud University Nijmegen, Donders Institute, Netherlands

How percepts, decisions and actions arise from the orchestrated activity of neuronal populations is probably one of the most fundamental questions in cognitive neuroscience.
Great progress has been made over the last decade in characterizing how perceptual decisions are implemented in the non-human primate brain. Neurophysiological studies in monkeys have shown how parietal and frontal areas accumulate evidence during perceptual decisions. These studies have however almost exclusively focused on the spiking activity of individual neurons, measured in one brain region at a time. Therefore, it remains an open question how these local computations are integrated across many brain regions into percepts, decisions and actions. In this symposium, we will discuss new findings, based on EEG/MEG in humans or depth electrodes in monkeys, which illustrate how perceptual decision-making emerges from local and large-scale interactions between neuronal populations. We will show that these interactions are typically oscillatory, and argue that cortical oscillations provide an exquisite window into the cortical computations producing decisions.
Donner will start off making the case of how oscillatory cortical population activity indexes different computational elements of simple perceptual decision processes. Then, Wyart will illustrate the rhythmic nature of evidence accumulation during perceptual categorisation, focusing on slow (2 Hz) fluctuations over parietal cortex. De Lange will show how top-down factors such as prior expectation and prior accumulated evidence influence oscillatory correlates of decision-making, on the basis of MEG data. Finally, Haegens will show novel electrophysiological data illustrating how alpha- and beta-band oscillations contribute to somatosensory decision-making in monkeys.
Together, the symposium will underscore the importance of studying the dynamic cortical network interactions underlying perceptual decisions.