Coordinate transformations in object recognition.

Markus Graf

doi:10.1037/0033-2909.132.6.920

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Coordinate transformations in object recognition.

Markus Graf

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Abstract

A basic problem of visual perception is how human beings recognize objects after spatial transformations. Three central classes of findings have to be accounted for: (a) Recognition performance varies systematically with orientation, size, and position; (b) recognition latencies are sequentially additive, suggesting analogue transformation processes; and (c) orientation and size congruency effects indicate that recognition involves the adjustment of a reference frame. All 3 classes of findings can be explained by a transformational framework of recognition: Recognition is achieved by an analogue transformation of a perceptual coordinate system that aligns memory and input representations. Coordinate transformations can be implemented neurocomputationally by gain (amplitude) modulation and may be regarded as a general processing principle of the visual cortex.

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Discrimination Learning Humans Memory, Short-Term Models, Psychological Neuropsychological Tests Orientation Pattern Recognition, Visual Problem Solving Reaction Time Space Perception Task Performance and Analysis Journal Article Research Support, Non-U.S. Gov't Review

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Markus Graf. 2006. Coordinate transformations in object recognition.. https://doi.org/10.1037/0033-2909.132.6.920

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