The hippocampus and transverse patterning guided by olfactory cues.

Normal rats and rats with hippocampal system damage were trained on a novel, olfactory version of the transverse-patterning task that involved the concurrent learning and continued performance of 3 partially ambiguous discrimination problems (A+B-, B+C-, C+A-). Animals with lesions of the fornix or perirhinal-entorhinal cortex acquired at least as rapidly as normal rats these problems presented in sequential blocks of trials involving the same stimulus pair. All groups also performed well on an initial test session when the order of stimulus pair presentations was randomized. Normal rats continued to discriminate appropriately in additional testing sessions with trials presented in random order. By contrast, both groups with hippocampal system damage performed poorly in continued random-order testing. These results extend the generality of the deficit in transverse patterning to the olfactory modality and demonstrate that the deficit is equivalent in magnitude after fornix or perirhinal-entorhinal damage. Findings also suggest that the transverse-patterning problem can be acquired transiently without critical hippocampal involvement, although continued performance relies on hippocampal function.

[1]  James L. McClelland,et al.  Why there are complementary learning systems in the hippocampus and neocortex: insights from the successes and failures of connectionist models of learning and memory. , 1995, Psychological review.

[2]  G. Handelmann,et al.  Hippocampus, space, and memory , 1979 .

[3]  D. Bilkey,et al.  Lesions of rat perirhinal cortex exacerbate the memory deficit observed following damage to the fimbria-fornix , 1995 .

[4]  J. W. Rudy,et al.  Some properties of configural learning: An investigation of the transverse-patterning problem. , 1992 .

[5]  S. Corkin Lasting Consequences of Bilateral Medial Temporal Lobectomy: Clinical Course and Experimental Findings in H.M. , 1984 .

[6]  H. Eichenbaum,et al.  Conservation of hippocampal memory function in rats and humans , 1996, Nature.

[7]  E. Bullmore,et al.  Society for Neuroscience Abstracts , 1997 .

[8]  H. Eichenbaum,et al.  Two functional components of the hippocampal memory system , 1994, Behavioral and Brain Sciences.

[9]  W. Scoville,et al.  LOSS OF RECENT MEMORY AFTER BILATERAL HIPPOCAMPAL LESIONS , 1957, Journal of neurology, neurosurgery, and psychiatry.

[10]  H. Eichenbaum,et al.  The hippocampus and memory for orderly stimulus relations. , 1997, Proceedings of the National Academy of Sciences of the United States of America.

[11]  J W Rudy,et al.  A comparison of kainic acid plus colchicine and ibotenic acid-induced hippocampal formation damage on four configural tasks in rats. , 1995, Behavioral neuroscience.

[12]  Dave G. Mumby,et al.  Rhinal cortex lesions and object recognition in rats , 1994 .

[13]  D. Amaral,et al.  Lesions of the perirhinal and parahippocampal cortices in the monkey produce long-lasting memory impairment in the visual and tactual modalities , 1993, The Journal of neuroscience : the official journal of the Society for Neuroscience.

[14]  M. Mishkin,et al.  Effects on visual recognition of combined and separate ablations of the entorhinal and perirhinal cortex in rhesus monkeys , 1993, The Journal of neuroscience : the official journal of the Society for Neuroscience.

[15]  M Meunier,et al.  Effects of rhinal cortex lesions combined with hippocampectomy on visual recognition memory in rhesus monkeys. , 1996, Journal of neurophysiology.

[16]  Kenneth W. Spence,et al.  The nature of the response in discrimination learning. , 1952 .

[17]  J. Bachevalier,et al.  Monkeys with early hippocampal formation lesions are impaired on the transverse patterning problem , 1995 .

[18]  J W Rudy,et al.  Rats with damage to the hippocampal-formation are impaired on the transverse-patterning problem but not on elemental discriminations. , 1995, Behavioral neuroscience.

[19]  L. Squire,et al.  Damage to the perirhinal cortex exacerbates memory impairment following lesions to the hippocampal formation , 1993, The Journal of neuroscience : the official journal of the Society for Neuroscience.

[20]  H Eichenbaum,et al.  Further studies of hippocampal representation during odor discrimination learning. , 1989, Behavioral neuroscience.

[21]  R. Sutherland,et al.  Configural association theory: The role of the hippocampal formation in learning, memory, and amnesia , 1989, Psychobiology.

[22]  D. Amaral,et al.  Lesions of perirhinal and parahippocampal cortex that spare the amygdala and hippocampal formation produce severe memory impairment , 1989, The Journal of neuroscience : the official journal of the Society for Neuroscience.

[23]  R. Sutherland,et al.  Configural association theory and the hippocampal formation: An appraisal and reconfiguration , 1995, Hippocampus.

[24]  R. Morris,et al.  Place navigation impaired in rats with hippocampal lesions , 1982, Nature.

[25]  D. Amaral,et al.  Perirhinal and postrhinal cortices of the rat: A review of the neuroanatomical literature and comparison with findings from the monkey brain , 1995, Hippocampus.

[26]  H. Eichenbaum,et al.  Complementary roles of the orbital prefrontal cortex and the perirhinal-entorhinal cortices in an odor-guided delayed-nonmatching-to-sample task , 1992 .

[27]  L. Jarrard On the role of the hippocampus in learning and memory in the rat. , 1993, Behavioral and neural biology.

[28]  L. Nadel,et al.  The Hippocampus as a Cognitive Map , 1978 .