Disruption of Spatial but Not Object-Recognition Memory by Neurotoxic Lesions of the Dorsal Hippocampus in Rats

• Published in: Behavioral neuroscience 1997-12, Vol.111 (6), p.1184-1196
• Main Authors: Duva, Christopher A, Floresco, Stan B, Wunderlich, Glen R, Lao, Terrance L, Pinel, John P. J, Phillips, Anthony G
• Format: Article
• Language: English
• Subjects: Amnesia - physiopathology; Anatomical correlates of behavior; Animal; Animals; Behavioral psychophysiology; Biological and medical sciences; Brain Injuries - physiopathology; Cerebral Cortex - injuries; Cerebral Cortex - pathology; Discrimination Learning - drug effects; Discrimination Learning - physiology; Disease Models, Animal; Excitatory Amino Acid Agonists; Fundamental and applied biological sciences. Psychology; Hippocampus; Hippocampus - drug effects; Hippocampus - injuries; Hippocampus - pathology; Hippocampus - physiopathology; Male; Maze Learning - drug effects; Maze Learning - physiology; Memory; Memory - drug effects; Memory - physiology; N-Methylaspartate; Neurology; Object Recognition; Orientation - drug effects; Orientation - physiology; Pattern Recognition, Visual - drug effects; Pattern Recognition, Visual - physiology; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Rats; Rats, Wistar; Rodents; Spatial Memory; Temporal Lobe - physiopathology; Time Factors
• ISSN: 0735-7044; 1939-0084
• DOI: 10.1037/0735-7044.111.6.1184

Ischemia-induced cell loss in the CA1 region of the dorsal hippocampus results in severe deficits on delayed non-matching-to-sample (DNMS), whereas hippocampectomy produces little or no impairment, suggesting that partial hippocampal damage is more detrimental to DNMS performance than total ablation. To test this hypothesis, rats with or without preoperative DNMS training were given partial cytotoxic lesions of the dorsal hippocampus. When tested, neither group displayed any DNMS deficits despite widespread cell loss in the CA1 and other regions of the dorsal hippocampus. In the final experiments, rats tested previously on DNMS were found to be impaired on the Morris water maze. The finding that partial hippocampal lesions disrupt spatial memory while leaving object-recognition memory intact indicates a specialized role for the hippocampus in mnemonic processes.