Recurrent seizures induce a reversible impairment in a spatial hidden goal task
| Autor: | John L. Kubie, Hai Lin, Gregory L. Holmes, Robert U. Muller |
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| Rok vydání: | 2009 |
| Předmět: |
Male
medicine.medical_specialty Time Factors Cognitive Neuroscience Hippocampus Morris water navigation task Audiology Spatial memory Article Task (project management) Developmental psychology Random Allocation Epilepsy Seizures Flurothyl medicine Animals Rats Long-Evans Cognitive decline Maze Learning Analysis of Variance medicine.disease Rats Space Perception Analysis of variance Cognition Disorders Psychology Goals Neuroscience Locomotion |
| Zdroj: | Hippocampus. 19:817-827 |
| ISSN: | 1098-1063 1050-9631 |
| DOI: | 10.1002/hipo.20565 |
| Popis: | A major question concerning the learning and memory deficits characteristic of epilepsy is the relative importance of the initial insult that leads to recurrent, unprovoked seizures versus the seizures themselves. A related issue is whether seizure-induced cognitive decline is permanent or reversible when convulsions cease. To address these problems, adult rats were extensively trained in the “spatial accuracy task,” a dry-land analog of the Morris water maze. This task allows the rat's estimate of the location of a hidden goal zone to be repeatedly measured within each behavioral session. One aim was to measure, in well-trained animals, the time course of any cognitive impairment caused by a daily flurothyl-induced generalized seizure over 11 days. A second aim was to look for possible recovery during 9 subsequent days with no seizures. We saw a cumulative degradation in spatial performance during the seizure days and reversal of the deficit after seizures were stopped such that performance returned to baseline. Interestingly, the rate of learning to an asymptote, the rate of performance decline during one-per-day seizures and the rate of relearning during the recovery period were all similar. Given that the hippocampus plays an important role in spatial memory and that it is the brain structure most vulnerable to abnormal excitation the implication is that the hippocampus remains essential for precise spatial navigation even after prolonged training in locating a fixed goal zone. Clinically, this finding questions the assumption that patients who experience seizures should return to a baseline cognitive level within hours. © 2009 Wiley-Liss, Inc. |
| Databáze: | OpenAIRE |
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