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Updated: May 31, 2026
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Randomized, Triple-Blind, and Parallel-Controlled Trial of Transcranial Direct Current Stimulation for Cognitive Rehabilitation after Stroke
Published on: June 6, 2025
Poststroke conscious visual deficit: clinical course and changes in cerebral activations
Nicolas Raposo1, Alexandra Séverac Cauquil, Jean François Albucher
1Service de Neurologie Vasculaire ; Fédération de Neurologie; Hôpital Purpan, Toulouse Cedex 9, France. raposo.n@chu-toulouse.fr
Neurorehabilitation and Neural Repair
|June 25, 2011
Summary
Visual perception significantly recovers after stroke-induced occipital lobe damage. Brain imaging reveals early recovery linked to visual cortex activation and neural pathways.
Area of Science:
- Neuroscience
- Clinical Neurology
- Neuroimaging
Background:
- Visual perception deficits after occipital lobe lesions, particularly stroke, are poorly understood.
- Mechanisms of visual recovery following focal brain injury remain largely unknown.
Purpose of the Study:
- To investigate the clinical course of conscious perceptive visual deficits after posterior cerebral artery infarct.
- To identify the neural substrates underlying visual recovery post-stroke.
Main Methods:
- Prospective study of 8 patients with striate cortex damage from acute posterior cerebral artery infarct.
- Assessment of color and motion perception from acute phase to 3 months.
- Functional magnetic resonance imaging (fMRI) to explore neural recovery substrates.
Main Results:
- Visual deficits varied from global to selective for color or motion in the acute phase.
- Significant improvements in color (29% to 70%) and motion (47% to 74%) perception were observed.
- Early lack of ipsilesional V1 activation shifted to include V1 and contralesional extrastriate cortex activation during follow-up. Ipsilesional and contralesional V4 activations correlated with better outcomes.
Conclusions:
- Early and extensive visual recovery is possible after partial acute posterior cerebral artery infarct.
- Spared areas within the ipsilesional V1 (primary visual cortex) and transcallosal pathways likely contribute to post-stroke visual recovery.
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