Ideographic Alexia without Involvement of the Fusiform Gyrus in a Korean Stroke Patient: A Serial Functional Magnetic Resonance Imaging Study

다국어 초록 (Multilingual Abstract)

Background Korean orthography is composed of Hanja (ideograms) and Hangul (phonograms). Based on previous studies, the fusiformgyrus has been associated with ideogram reading. We examine serial functional magnetic resonance imaging (fMRI) images in a patient exhibitingdissociation of Hanja and Hangul reading to identify brain areas associated with Hanja reading.
Case Report fMRI were taken of a 63-year-old man showing profound Hanja alexia with normal Hangul reading after an acute stroke involvingthe left frontal and parietal lobes, who later spontaneously recovered his Hanja reading ability. Scans were taken while performingHanja and Hangul reading tasks on three occasions. As a result, in spite of having profound Hanja alexia, partial activation of the fusiformgyrus was observed on the first fMRI. Serial fMRI scans showed activation of the bilateral middle frontal gyri that increased in parallel withthe patient’s recovery of Hanja reading.
Conclusions The frontal lobe, not only fusiform gyrus, may play role in reading Hanja, although more evidence is needed.

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