Lesions of the anteroventral or anteromedial thalamic nuclei impair working and reference memory in a twelve-arm radial maze
| dc.contributor.author | Byatt, Graham | |
| dc.date.accessioned | 2021-10-15T02:03:03Z | |
| dc.date.available | 2021-10-15T02:03:03Z | |
| dc.date.issued | 1995 | en |
| dc.description.abstract | Controversy still surrounds the neural bases of diencephalic amnesia. Recent research in rats suggests that incidental damage to the anterior thalamus (AT) may be responsible for impairments following other experimental procedures such as dorsomedial thalamic (DM) lesions or pyrithiamine-induced thiamine deficiency (PTD). Part One of this study assessed the effects of small radio-frequency lesions, confined to either the anteroventral (AV) or anteromedial (AM) nuclei of the AT, on the performance of naive rats on a 12-arm radial maze procedure (8 arms baited). Both lesions impaired reference memory and working memory over an extended period of testing. Latency measures in the radial maze showed that these impairments were not due to general behavioural deficits. The only difference in te1ms of maze activity was that control rats, but not lesioned rats, took longer to run to the ends of previously baited arms. Concurrent testing in an activity chamber found only that control rats tended to show more marked within-session habituation. Part Two investigated the relative contributions of intramaze and extramaze cues to radial maze performance and showed that for all groups both working memory and reference memory were impaired following the removal of extramaze cues; the removal of the previous intramaze cues further impaired perf01mance relative to the original conditions. In the most restricted cue condition, reference memory pe1formance was reduced to chance whereas working memory performance was impaired yet still considerably better than chance. Given that all groups were affected in a similar fashion by the cue manipulations, it is possible that AT lesions produce a general deficit rather than a specific one (e.g. spatial/working memory). In general, this study showed that minor damage to the AT, comparable to that sustained incidentally following other experimental procedures was sufficient to impair pe1formance in the radial maze, a task known to be sensitive to damage to the hippocampal system. The impairments following AT lesions are likely to be due to disruptions of circuits involving the limbic cortex and hippocampal system. | en |
| dc.identifier.uri | https://hdl.handle.net/10092/102717 | |
| dc.identifier.uri | http://dx.doi.org/10.26021/11851 | |
| dc.language | English | |
| dc.language.iso | en | |
| dc.publisher | University of Canterbury | en |
| dc.rights | All Rights Reserved | en |
| dc.rights.uri | https://canterbury.libguides.com/rights/theses | en |
| dc.subject | Memory disorders | en |
| dc.subject | Brain damage | en |
| dc.subject | Thalamus--Wounds and injuries | en |
| dc.subject | Animal memory | en |
| dc.subject | Rats--Psychology | en |
| dc.title | Lesions of the anteroventral or anteromedial thalamic nuclei impair working and reference memory in a twelve-arm radial maze | en |
| dc.type | Theses / Dissertations | en |
| thesis.degree.discipline | Psychology | en |
| thesis.degree.grantor | University of Canterbury | en |
| thesis.degree.level | Masters | en |
| thesis.degree.name | Master of Arts | en |
| uc.bibnumber | 538434 | en |
| uc.college | Faculty of Science | en |