Central achromatopsia, associative visual agnosia, and prosopagnosia due to fusiform gyrus infarction: A case report
A. OGATA, S. TOHGO, M. KAWATSU,
K. KAWAHIRA, N. TANAKA
Department of Rehabilitation and Physical Medicine,
Faculty of Medicine, Kagoshima University, Japan.
Abstract:
75 -year-old woman was admitted to our hospital complaining of problems with color recognition, objects, and individual faces. A massive cerebral infarction in the left occipital lobe in 1984 had caused right homonymous hemianopsia and pure alexia. Two weeks before arriving at our hospital, she had complained of color disturbances, and difficulty with recognition of objects and faces, which followed a sudden blindness that had lasted for 1 hour. CT and MRI revealed a recent infarction localized in the right fusiform gyrus and an old, massive infarction in the left occipital lobe. At the time of admission, she could recognize the face of real persons and objects but could not recognize them in pictures or line drawings. She could recognize the value of colors as black and white, but could not identify colors in a painting of a flower and was unable to match colors. No deficit in visuospatial cognition was noted. She was diagnosed as having associative visual agnosia, prosopagnosia, and achromatopsia due to recent cerebral attack. A few days after admission she recovered red and yellow color cognition； blue and green cognition returned about 1 month after admission.
These symptoms, combined with the CT and MRI findings, suggest that the (right) fusiform gyrus, as well as area V4 as noted in monkey studies, is important in the transaction or transmission of visual information about objects, faces, and colors. Additionally, the preservation of visuospatial cognition in the present case suggests that the projection to the parietal lobe from the occipital lobe for visuospatial cognition diverged before the fusiform gyrus. The recovery of color cognition is understandable in the present case given the large number of cells in this region which are sensitive to red color.
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