Differential Roles of Dorsal Hippocampal Subregions in Spatial Working Memory With Short Versus Intermediate Delay

Lee, Inah
Kesner, Raymond P.

¹Department of Neurobiology and Anatomy, University of Texas Houston Medical School
²Department of Psychology, University of Utah.

³Correspondence concerning this article should be addressed to Raymond P. Kesner, Department of Psychology, University of Utah, 390S 1530E Room 502, Salt Lake City, Utah 84112. E-mail [email protected].

This research was supported by the Human Frontiers Science Program and by National Science Foundation Grant NSFIBN 9817583.

Received Date: December 3, 2002; Revised Date: April 8, 2003; Accepted Date: April 9, 2003

Behavioral Neuroscience 117(5):p 1044-1053, October 2003.

In order to determine the role of subregions of the hippocampus in spatial working memory, this study combined selective neurotoxic lesions of the hippocampal subregions with a simple delayed nonmatching-to-place task on a radial maze in rats. Lesions of the dentate gyrus or the CA3, but not the CA1, subregion of the hippocampus induced a deficit in the acquisition of the task with short-term delays (i.e., 10 s) and impaired performance of the task in a novel environment. All subregional lesions produced sustained impairment in performing the task with intermediate-term delays (i.e., 5 min) when rats were tested in a familiar environment. The results suggest a dynamic interaction among the dorsal hippocampal subregions in processing spatial working memory, with the time window (i.e., delay) of a task recognized as an essential controlling factor.