Deficits in spatial working memory after unilateral temporal lobectomy in man.

Forty neurosurgical patients and 20 controls were tested on a series of computerized tasks (the executive golf, structured golf and rotate tasks) designed to investigate spatial working memory. As defined by Olton [Spatial Abilities, Academic Press, New York, 1982], spatial working memory involves the encoding of specific and contextual information within the spatial domain. Right temporal lobectomy patients were significantly impaired on all three tasks, while the left temporal lobectomy patients showed a less significant overall impairment only on the structured golf task. Although there was no statistically significant differences between the two patient groups on the three tasks, the results point towards a robust deficit in spatial memory associated with right temporal lobectomy. The results provide further evidence for the role of the mesial temporal lobe structures in the processing and encoding of spatial information.