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Published on: April 16, 2014
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Rise and fall of the two visual systems theory
Yves Rossetti1, Laure Pisella2, Robert D McIntosh3
1Inserm UMR-S 1028, CNRS UMR 5292, ImpAct, Centre de Recherche en Neurosciences de Lyon, université Lyon-1, 16, avenue Lépine, 69676 Bron, France; Plate-forme « Mouvement et Handicap », Hôpital Henry-Gabrielle, Hospices Civils de Lyon, 20, route de Vourles, Saint-Genis-Laval, France.
Annals of Physical and Rehabilitation Medicine
|May 27, 2017
Summary
The dual visual system theory, separating perception and action, is challenged. New findings suggest optic ataxia and visual agnosia do not support a strict perception-action dissociation, favoring a unified perception-action model.
Area of Science:
- Neuroscience
- Cognitive Psychology
- Visual Perception
Background:
- The dual visual system theory posits separate pathways for perception and action.
- This theory is supported by psychophysical, anatomical, and neuropsychological evidence.
- Neuropsychological studies identified optic ataxia and visual agnosia as key deficits.
Purpose of the Study:
- To re-evaluate the strict dissociation between perception and action in the visual system.
- To examine the validity of optic ataxia and visual agnosia as distinct markers.
- To explore the interconnectedness of visual brain networks.
Main Methods:
- Review of psychophysical, anatomical, and neuropsychological studies.
- Analysis of behavioral data on sensory and motor responses.
- Examination of clinical deficits like optic ataxia and visual agnosia.
Main Results:
- The proposed double dissociation between optic ataxia and visual agnosia is no longer considered tenable.
- Optic ataxia does not support a clear perception-action dissociation and may relate to action blindsight.
- Observed dissociations apply to elementary or automatic actions, not higher-level functions.
Conclusions:
- The strict separation of perception and action within the visual system is questioned.
- Optic ataxia highlights deficits in automatic action organization.
- A unified perception-action model, considering the visual brain as a functional ensemble, is advocated.
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