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Short-term memory for figure-ground organization in the visual cortex.

ABSTRACT: Whether the visual system uses a buffer to store image information and the duration of that storage have been debated intensely in recent psychophysical studies. The long phases of stable perception of reversible figures suggest a memory that persists for seconds. But persistence of similar duration has not been found in signals of the visual cortex. Here, we show that figure-ground signals in the visual cortex can persist for a second or more after the removal of the figure-ground cues. When new figure-ground information is presented, the signals adjust rapidly, but when a figure display is changed to an ambiguous edge display, the signals decay slowly--a behavior that is characteristic of memory devices. Figure-ground signals represent the layout of objects in a scene, and we propose that a short-term memory for object layout is important in providing continuity of perception in the rapid stream of images flooding our eyes.

SUBMITTER: O'Herron P

PROVIDER: S-EPMC2707495 | biostudies-literature | 2009 Mar

REPOSITORIES: biostudies-literature

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Short-term memory for figure-ground organization in the visual cortex.

O'Herron Philip P von der Heydt Rüdiger R

Neuron 20090301 5

Whether the visual system uses a buffer to store image information and the duration of that storage have been debated intensely in recent psychophysical studies. The long phases of stable perception of reversible figures suggest a memory that persists for seconds. But persistence of similar duration has not been found in signals of the visual cortex. Here, we show that figure-ground signals in the visual cortex can persist for a second or more after the removal of the figure-ground cues. When ne ...[more]

PMID: 19285475

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