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Raymond Kesner"A process analysis of subregional contributions to hippocampal function"

Abstract :

My presentation is guided by the assumptions made by computational models concerning the operation of specific functions assigned to the hippocampus by developing a set of behavioral paradigms and to examine subregional specificity (dorsal and ventral dentate gyrus, dorsal CA3 and dorsal CA1) of the hippocampus.
The importance of examining differential contributions of the subregions of the hippocampus is to understand information flow within the hippocampus, so that it will be possible to determine input-output functions of the hippocampus and understand the contribution that the hippocampus makes to the overall processing of mnemonic information and memory representation. I will show that the dorsal dentate gyrus supports conjunctive encoding, spatial and context-based pattern separation, and remote memory and the ventral dentate gyrus supports pattern separation for odors. The CA3 supports associative processes including arbitrary associations, and pattern completion and the CA1 supports temporal pattern separation, sequence learning, and promotes consolidation processes.

Selected publications

Rolls, E. T., & Kesner, R. P. (2006). A computational theory of hippocampal function, and empirical tests of the theory. Progress in Neurobiology ,79.1-48.

Kesner, R. P., & Hopkins, R. O. (2006). Mnemonic functions of the hippocampus: A comparison between animals and humans. Biological Psychology, 73, 3-18.

Goodrich-Hunsaker, N.J., Hunsaker, M. R., & Kesner, R. P. (2005). Dissociating the role of the parietal cortex and dorsal hippocampus for spatial information processing. Behavioral Neuroscience, 119, 1307-1315.

Kesner, R. P., Hunsaker, M. R. & Gilbert P. E. (2005). The role of CA1 in the acquisition of an object-trace-odor paired associate task. Behavioral Neuroscience, 119, 781-786.

Gold, E., Kesner, R. P. (2005). The role of the CA3 subregion of the dorsal hippocampus in spatial pattern completion in the rat. Hippocampus, 15, 808-814.

Scientific focus :

Theoretical and applied aspects associated with the neurobiological basis of learning and memory.

Development of animal models paralleling mnemonic symptomatology in brain damaged patients.

In general, I am interested in the neurobiological basis of learning and memory in animals and humans focussing on applied and theoretical issues. From a theoretical perspective, I have emphasized the importance of a multidimensional model of memory pointing to the existence of differential neuroanatomical contributions to different forms of memory. More specifically, I have proposed that memory organization is based on functionally separate but interdependent attributes of memory, such as space, time, response, affect and sensory perception in animals and humans. In humans, I have added a language attribute. In this attribute model it is assumed that any specific memory is not only composed of a set of attributes, but is further organized into a data-based memory system akin to episodic or working memory and a knowledge-based memory akin to semantic or reference memory. Furthermore, it is proposed that different neural regions and neural circuits subserve these different memory attributes. Thusfar, tests have been devised to measure specific data-based or working memory experiments for each of the proposed attributes and it can be shown that within the data-based memory system these attributes can operate independent of each other as observed in a 4-way dissociation among these attributes. For example, the hippocampus mediates primarily spatial location and temporal attributes, the caudate nucleus mediates primarily response attributes, the medial extrastriate mediates primarily visual object information as an example of sensory-perceptual attributes, and the amygdala mediates primarily affect attributes...

Yoon Cho de l'INCIA