Spatial learning tasks

The influence of BDNF regulation of synaptic function on behaviour has still to be fully determined. Rats treated with antibodies to BDNF (icv) were signihcantly impaired in a spatial learning task (Mu et ah, 1999). Levels of BDNF expression in CAl were rapidly and selectively increased following contextual fear conditioning, a form of learning also dependent on the hippocampus (Hall et ah, 2000). 

Similarly, intrahippocampal injections of 8-OH-DPAT induced no change in performance levels of the rat trained to run in a radial maze (Buhot et al. 1995). However, the intrahippocampal injection of the 5-HTjg receptor agonist CP-93,129 [3-(l,2,5,6-tetrahydropyrid-4-yl] pyrrolo [3,2-6] pyrid-5-one] induced a higher frequency of reference memory errors than of working memory. It was concluded that stimulation of 5-HT,g receptors in the CAl field of the dorsal hippocampus impairs performance of rats in a spatial learning task. 

Rouillon F, Serrurier D, Miller H, et al Prophylactic efficacy of maprotiline on unipolar depression relapse. J Chn Psychiatry 52 423-431, 1991 Rowan MJ, Cullen WK, Moulton B Buspirone impairment of performance of passive avoidance and spatial learning tasks in the rat. Psychopharmacology 100 393-398,... 

Greiner RS, Moriguchi T. Hutton A. Slotnick BM, SalemN Jr. Rats with low levels of brain docosahexaenoic acid show impaired performance in olfactory-based and spatial learning tasks. Lipids 1999 34 S239-243. 

Schuster, G.M., Schmidt, W.J., 1992. D-cycloserine reverses the working memory impairment of hippocampal-lesioned rats in a spatial learning task. Eur. J. Pharmacol. 224, 97-98. 

Greiner, R.S., Moriguchi, T., Hutton, A., Slotnick, B.M., and Salem, N., Jr. (1999) Rats with Low Levels of Brain Docosahexaenoic Acid Show Impaired Performance in Olfactory-Based and Spatial Learning Tasks, Lipids 34, S239-S243. 

The results are inconsistent with those of the previous study, to the extent that there was no significant difference in the visual discrimination learning between the groups. In the spatial learning task there were significant differences in the number of days required to reach criterion, with the performance of both maternally and permanently exposed groups inferior to that of controls. 

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