Anton's syndrome following callosal disconnection
J Abutalebi1, C Arcari, M A Rocca
1Centre of Cognitive Neuroscience, University Vita-Salute San Raffaele, Milan, Italy. abutalebi.jubin@hsr.it
Behavioural Neurology
|August 30, 2007
Summary
Anton's syndrome, or anosognosia for cortical blindness, can result from lesions disconnecting the occipital cortices, not just bilateral damage. This case study highlights a novel cause for this rare neurological disorder.
Area of Science:
- Neurology
- Neuroscience
- Ophthalmology
Background:
- Anosognosia for cortical blindness, known as Anton's syndrome, is a rare condition typically associated with bilateral occipital lobe lesions.
- This syndrome involves a lack of awareness of blindness despite intact visual stimuli processing.
Observation:
- A case study of a patient with Anton's syndrome following an ischemic lesion.
- The lesion was confined to the left occipital lobe and involved the corpus callosum.
Findings:
- Neuropsychological, morphological, and functional neuroimaging (SPECT and fMRI) were conducted.
- Findings suggest that Anton's syndrome can arise from lesions that disconnect the occipital cortices, even if unilateral.
Implications:
- This expands the understanding of the pathophysiology of Anton's syndrome.
- It suggests that disruption of visual information pathways, not just direct bilateral damage, can lead to anosognosia for cortical blindness.
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