Scientific Understanding of Consciousness
Consciousness as an Emergent Property of Thalamocortical Activity

Probabilistic Reasoning by Neurons

 

Nature 447, 1075-1080 (28 June 2007)

Probabilistic reasoning by neurons

Tianming Yang¹ & Michael N. Shadlen¹

Howard Hughes Medical Institute, Department of Physiology and Biophysics, National Primate Research Center, University of Washington, Box 357290, Seattle, Washington 98195–7290, USA

(paraphrase)

Decision-making is a complicated process that is often based on more than one source of evidence. The brain needs to combine these sources to maximize the chance of achieving a correct decision or to achieve another related goal. Recent advances in neuroscience are beginning to expose the neurobiological mechanisms that underlie simple decisions. It has been demonstrated that, when the outcome of a decision is an eye movement, a neural correlate of the evolving decision can be recorded in brain areas associated with high level motor planning and attention allocation. More specifically, neurons in the lateral intraparietal area (LIP) have been shown to accumulate sensory information provided by earlier visual cortex when a decision is being formed. The mechanism mimics statistical decision processes that accrue evidence sequentially in the form of a log likelihood ratio (logLR) that favours one outcome over another. Therefore, it has been hypothesized that a neuronal substrate of probability integration exists in area LIP.

(end of paraphrase)

 

 

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