Crossed aphasia in a dextral

J Korean Neurol Assoc > Volume 15(2); 1997 > Article

Journal of the Korean Neurological Association 1997;15(2): 382-387.

교차성 실어증1례

조용진, 박규현

부산대학교 의대 신경과

Crossed aphasia in a dextral

Yong Jin Jo, M.D., Kyu Hyun Park, M.D.

Department of Neurology, College of Medicine, Pusan National University

Abstract

Crossed aphasia refers to a combination of aphasia and right hemiparesis in a left handed person or left hemiparesis and aphasia in a dextral. While crossed aphasia is not infrequent at all among left-handers, it remains an extremely rare event in dextrals. Its incidence is probably about 0.4% after right hemispheric lesions and prevalence is about 1% among right-handed aphasics. The neurobiological mechanisms of this phenomenon are unknown, and the neuropsychological correlations are only incompletely understood. We report a case of crossed aphasia in a 61-year-old right-handed woman who presented with sudden, severe global aphasia and left hemiplegia without any personal or family history of left-handedness. Brain MR image clearly showed a right hemispheric infarction in the territory of the right middle cerebral artery and brain SPECT also displayed reduction of regional cerebral blood flow in the right hemisphere sparing the left hemisphere. In this patient, cerebral dominance for speech seems to lay in the right hemisphere, while dominance for limb praxis seems to lay in the left as the patient did not develop right limb apraxia. This case provides evidence that cerebral dominance for speech and handedness in dextrals can be dissociated. It also suggests that crossed aphasia in a dextral may be severe and persisting.