title: Selective fimbria and thalamic lesions differentially impair forms of working memory in rats.
abstract: Several series of experiments were designed to compare the effects of selective lesions of the fimbria or of thalamic nuclei on three different tasks involving working memory in rats: object recognition, place recognition, and the radial arm maze test. The main effects of fimbria lesions were as follows: they produced deficits in the radial maze; object recognition was spared or even facilitated, whereas place recognition was impaired. Electrolytic lesions of either centromedian-parafascicularis (CM-Pf) or dorsomedialis (DM) nuclei produced highly significant deficits in the radial maze test but spared object and place recognition. Ibotenate lesions of the CM-Pf had no effect on any test, which means that the critical structure in the effects of the electrolytic lesions of the CM-Pf was the fasciculus retroflexus (FR). These data may contribute two main points to animal models of hippocampal and thalamic amnesia: (1) different forms of working memory in rats might have different neural bases and (2) the FR may be involved in learning and memory processes.
authors.affiliation: Laboratoire de Psychophysiologie, Université Paris VII, France.
authors.forename: M
authors.initials: M
authors.lastname: M'Harzi
authors.forename: L E
authors.initials: LE
authors.lastname: Jarrard
authors.forename: F
authors.initials: F
authors.lastname: Willig
authors.forename: A
authors.initials: A
authors.lastname: Palacios
authors.forename: J
authors.initials: J
authors.lastname: Delacour
mesh_terms: D000818:Animals; D001931:Brain Mapping; D004193:Discrimination Learning / Q000502:physiology*; D005556:Form Perception / Q000502:physiology; D006624:Hippocampus / Q000502:physiology*; D008297:Male; D011939:Mental Recall / Q000502:physiology*; D009434:Neural Pathways / Q000502:physiology; D009949:Orientation / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D012153:Retention, Psychology / Q000502:physiology; D012688:Septum Pellucidum / Q000502:physiology*; D013787:Thalamic Nuclei / Q000502:physiology*