title: Olfactory discrimination learning in mice lacking the fragile X mental retardation protein.
abstract: An automated training system was used to compare the behavior of knockout (KO) mice lacking the fragile X mental retardation protein with that of wild-type (WT) mice (C57Bl/6 strain) in the acquisition and retention of olfactory discriminations. KO and WT mice did not differ in the acquisition of a four-stage nose poke shaping procedure. In two separate experiments, mutant mice required substantially more training to acquire a series of novel olfactory discrimination problems than did control mice. The KO mice required significantly more sessions to reach criterion performance, made significantly more errors during training, and more often failed to acquire discriminations. Both KO and WT mice showed similar error patterns when learning novel discriminations and both groups showed evidence of more rapid learning of later discriminations in the problem series. Both groups showed significant long-term memory two or four weeks after training but WT and KO mice did not differ in this regard. A group of well-trained mice were given training on novel odors in sessions limited to 20-80 trials. Memory of these problems at two day delays did not differ between WT and KO mice. Tests using ethyl acetate demonstrated that WT and KO mice had similar odor detection thresholds.
authors.affiliation: Psychiatric Institute, Department of Psychiatry (M/C 912), College of Medicine, University of Illinois at Chicago, 1601 W. Taylor Street, Chicago, IL 60612, USA. jrlarson@uic.edu
authors.forename: John
authors.initials: J
authors.lastname: Larson
authors.forename: Daniel
authors.initials: D
authors.lastname: Kim
authors.forename: Roseanne C
authors.initials: RC
authors.lastname: Patel
authors.forename: Christina
authors.initials: C
authors.lastname: Floreani
mesh_terms: D000085:Acetates; D000818:Animals; D004193:Discrimination Learning / Q000502:physiology*; D004195:Disease Models, Animal; D051860:Fragile X Messenger Ribonucleoprotein 1 / Q000235:genetics* / Q000378:metabolism; D008607:Intellectual Disability / Q000235:genetics / Q000503:physiopathology*; D008297:Male; D008568:Memory / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009812:Odorants; D011930:Reaction Time / Q000502:physiology; D012903:Smell / Q000502:physiology*
chemical_list: D000085:Acetates; D051860:Fragile X Messenger Ribonucleoprotein 1; C497684:Fmr1 protein, mouse; C007650:ethyl acetate