Gerstmann syndrome: historic and current perspectives.

This chapter offers a perspective on the origin, operational definition, historic vicissitudes, and current status of Gerstmann syndrome. The main issues and controversy accompanying Gerstmann syndrome throughout the years are reviewed. The clinical picture of Gerstmann syndrome as it emerges from a series of modern-day pure cases is described. In current clinical practice, a diagnosis of Gerstmann syndrome indicates the concomitant presence of four acquired symptoms: finger agnosia, acalculia, left-right disorientation, and agraphia. Finally, based on empiric work conducted in recent years, the chapter concludes with a new interpretation of Gerstmann syndrome. If seen as an instance of intraparietal disconnection, this classic parietal syndrome will acquire fresh clinical and theoretic significance.