The hippocampus has been implicated in the learning and memory of arrays of spatial cues. Certain theories of the function of the hippocampus have stressed the importance of the hippocampus in learning about configurations of stimuli that have non-linear associations. Recent evince has suggested that the hippocampus may not be responsible for learning about unique configurations but rather the unique spatial relationships formed by a configuration of visual cues. This thesis examines the effects of hippocampal lesions on visual configural discriminations, in which the solution relies on learning the features that are necessary for configural learning, and also discriminations in which the solution of the task relies on learning the spatial structure of the features that form the configurations. It was found that hippocampal lesions made after acquisition impaired performance of a structural discrimination. Hippocampal lesions did not impair performance of previously acquired configural discriminations. A probe test revealed that although hippocampal lesioned and control rats do not differ on performance of a configural discrimination that does not require learning structural information, control rats learn the structural features of the configurations to a greater extent than hippocampal lesioned rats. Hippocampal lesioned rats were impaired at learning structural information when a task explicitly demanded, and when the structural features were incidental to the requirements of a task. The results are discussed with regards to a configural account of hippocampal dependent allocentric spatial learning, and also theories of hippocampal dependent stimulus representation
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:583555 |
| Date | January 2005 |
| Creators | Sanderson, David John |
| Publisher | Cardiff University |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://orca.cf.ac.uk/55382/ |
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