Memory impairment and spatial disorientation following a left retrosplenial lesion.

We treated a patient in whom a left retrosplenial lesion resulted in memory impairment and spatial disorientation. A 31 year old, right handed man was admitted to our hospital after the sudden onset of headache. He was alert, attentive and cooperative, and showed no motor or sensory deficits. Although intelligence was preserved, memory was obviously deficient. The patient proceeded in wrong directions after he left his hospital room and subsequently his home. Neuroimaging revealed a subcortical hematoma in the left cingulate isthmus, while single-photon emission computed tomography demonstrated decreased perfusion in the splenium and left parietal lobe.