title: A case of tactile agnosia with a lesion restricted to the post-central gyrus.
abstract: Tactile agnosia has been described after lesions of the primary sensory cortex but the exact location and extension of those lesions is not clear. We report the clinical features and imaging findings in a patient with an acute ischemic stroke restricted to the primary sensory area (S1). A 73-year-old man had a sudden onset of a left alien hand, without left hemiparesis. Neurological examination showed intact primary sensory functions, but impaired recognition of shape, size (macrogeometrical) and texture (microgeometrical) of objects; damage confined to the post-central gyrus, sparing the posterior parietal cortex was demonstrated on MRI. An embolic occlusion of the anterior parietal artery was suspected as mechanism of stroke. Tactile agnosia with impaired microgeometrical and macrogeometrical features' recognition can result from a single lesion in the primary sensory cortex (S1) in the right parietal hemisphere, sparing other regions of the cerebral cortex which presumably participate in tactile object recognition.
authors.affiliation: Department of Neurology and Psychiatry, The National Institute of Medical Sciences and Nutrition, Salvador Zubiran, Mexico City, Mexico. bestanol@hotmail.com
authors.forename: Bruno
authors.initials: B
authors.lastname: Estañol
authors.forename: José Fidel
authors.initials: JF
authors.lastname: Baizabal-Carvallo
authors.forename: Horacio
authors.initials: H
authors.lastname: Sentíes-Madrid
mesh_terms: D000368:Aged; D000377:Agnosia / Q000209:etiology*; D002545:Brain Ischemia / Q000150:complications; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009460:Neurologic Examination; D013003:Somatosensory Cortex / Q000473:pathology*; D020521:Stroke / Q000150:complications* / Q000209:etiology / Q000473:pathology*