J Korean Neurol Assoc.  1997 Apr;15(2):382-387.

Crossed aphasia in a dextral

• Jo YJ
• Park KH

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 speechseems to lay in the right hemisphere, while dominance for limb praxis seemsto 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.

MeSH Terms

Aphasia*
Apraxias
Brain
Dominance, Cerebral
Extremities
Female
Functional Laterality
Hand
Hemiplegia
Humans
Incidence
Infarction
Middle Aged
Middle Cerebral Artery
Paresis
Prevalence
Tomography, Emission-Computed, Single-Photon