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Processing spatial information in the sensorimotor branch of the visual system.

B Bridgeman·A Gemmer·T Forsman·V Huemer
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Abstract

We distinguish two representations of visual space: a cognitive representation drives perception, and a sensorimotor representation controls visually guided behavior. Spatial values in the two representations are separated with the Roelofs effect: a target within an off-center frame appears biased in a location opposite the direction of the frame. The effect appears for a verbal measure (cognitive) but not for a jab at the target (sensorimotor). A 2-s response delay induces a Roelofs effect in the motor measure, showing the limit of motor memory. Motor error is not correlated with reaction time. Subjects could strike one of two identical targets, a process involving choice, without intrusion of a Roelofs effect, showing that the sensorimotor system can use its own coordinates even when a cognitive choice initiates the motor processing.

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CognitionHumansOptical IllusionsPsychomotor PerformanceReaction TimeVisual PathwaysVisual PerceptionJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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B Bridgeman, A Gemmer, T Forsman, V Huemer. 2000. Processing spatial information in the sensorimotor branch of the visual system.. https://doi.org/10.1016/s0042-6989(00)00193-0

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