Agnosia

Research by A.R. Giovagnoli and colleagues in dementia provides new insights

"Longitudinal clinical and neuropsychological assessment, combined with magnetic resonance imaging (MRI), spectroscopy, and positron emission tomography (PET) were used. Sequential neuropsychological evaluations performed during a period of 9 years since disease onset showed the appearance of apperceptive and associative visual agnosia, alexia without agraphia, agraphia, finger agnosia, and prosopoagnosia, but excluded dementia. MRI showed moderate diffuse cortical atrophy, with predominant atrophy in the left posterior cortical areas (temporal, parietal, and lateral occipital cortical gyri). 18FDG-PET showed marked bilateral posterior cortical hypometabolism; proton magnetic resonance spectroscopic imaging disclosed severe focal N-acetyl-aspartate depletion in the left temporoparietal and lateral occipital cortical areas," wrote A.R. Giovagnoli and colleagues.

The researchers concluded: "Selective metabolic alterations and neuronal loss in the left temporoparietooccipital cortex may determine progressive visual agnosia in the absence of dementia."

Giovagnoli and colleagues published their study in Neurological Sciences (The neuropsychological and neuroradiological correlates of slowly progressive visual agnosia. Neurological Sciences, 2009;30(2):123-131).

For more information, contact A.R. Giovagnoli, Ist Nazl Neurology Carlo Besta, Dept. of Clinic Neuroscience, Neuropsychol Laboratory, Via Celoria 11, I-20133 Milan, Italy.

Publisher contact information for the journal Neurological Sciences is: Springer, 233 Spring St., New York, NY 10013, USA.

Keywords: Italy, Milan, Agnosia, Central Nervous System Disease, Dementia, Dyslexia, Magnetic Resonance, Neuroimaging, Spectroscopy, Surgery.

This article was prepared by Pain & Central Nervous System Week editors from staff and other reports. Copyright 2009, Pain & Central Nervous System Week via NewsRx.com.