Original Research ARTICLE
Attention, uncertainty, and free-energy
- The Wellcome Trust Centre for Neuroimaging, Institute of Neurology, University College London, London, UK
We suggested recently that attention can be understood as inferring the level of uncertainty or precision during hierarchical perception. In this paper, we try to substantiate this claim using neuronal simulations of directed spatial attention and biased competition. These simulations assume that neuronal activity encodes a probabilistic representation of the world that optimizes free-energy in a Bayesian fashion. Because free-energy bounds surprise or the (negative) log-evidence for internal models of the world, this optimization can be regarded as evidence accumulation or (generalized) predictive coding. Crucially, both predictions about the state of the world generating sensory data and the precision of those data have to be optimized. Here, we show that if the precision depends on the states, one can explain many aspects of attention. We illustrate this in the context of the Posner paradigm, using the simulations to generate both psychophysical and electrophysiological responses. These simulated responses are consistent with attentional bias or gating, competition for attentional resources, attentional capture and associated speed-accuracy trade-offs. Furthermore, if we present both attended and non-attended stimuli simultaneously, biased competition for neuronal representation emerges as a principled and straightforward property of Bayes-optimal perception.
Keywords: attention, biased competition, precision, free-energy, perception, generative models, predictive coding
Citation: Feldman H and Friston KJ (2010) Attention, uncertainty, and free-energy. Front. Hum. Neurosci. 4:215. doi: 10.3389/fnhum.2010.00215
Received: 04 August 2010;
Paper pending published: 24 September 2010;
Accepted: 18 October 2010; Published online: 02 December 2010
Edited by:Sven Bestmann, University College London, UK
Reviewed by:William Milberg, Harvard Medical School, USA
Tamer Demiralp, Istanbul University, Turkey
Laurence T. Maloney, New York University, USA
Copyright: © 2010 Feldman and Friston. This is an open-access article subject to an exclusive license agreement between the authors and the Frontiers Research Foundation, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are credited.
*Correspondence: Karl J. Friston, Wellcome Trust Centre for Neuroimaging, Institute of Neurology, Queen Square, London WC1N 3BG, UK. e-mail: firstname.lastname@example.org