Posterior parietal cortex neurons encode target motion in world-centered coordinates.

Uwe J Ilg; Stefan Schumann; Peter Thier

doi:10.1016/j.neuron.2004.06.006

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Posterior parietal cortex neurons encode target motion in world-centered coordinates.

Uwe J Ilg·Stefan Schumann·Peter Thier

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Abstract

The motion areas of posterior parietal cortex extract information on visual motion for perception as well as for the guidance of movement. It is usually assumed that neurons in posterior parietal cortex represent visual motion relative to the retina. Current models describing action guided by moving objects work successfully based on this assumption. However, here we show that the pursuit-related responses of a distinct group of neurons in area MST of monkeys are at odds with this view. Rather than signaling object image motion on the retina, they represent object motion in world-centered coordinates. This representation may simplify the coordination of object-directed action and ego motion-invariant visual perception.

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Action Potentials Animals Fixation, Ocular Macaca mulatta Male Motion Perception Neurons Orientation Parietal Lobe Photic Stimulation Pursuit, Smooth Retina Visual Pathways Journal Article Research Support, Non-U.S. Gov't

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Uwe J Ilg, Stefan Schumann, Peter Thier. 2004-07-08. Posterior parietal cortex neurons encode target motion in world-centered coordinates.. https://doi.org/10.1016/j.neuron.2004.06.006

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