title: Changes in task demands alter the pattern of zif268 expression in the dentate gyrus.
abstract: Granule cells of the dentate gyrus (DG) are thought to disambiguate similar experiences--a process termed pattern separation. Using zif268 as a marker of cellular activity, DG function was assessed in rats performing two tasks: a place task (go east) and a response task (turn right). As these tasks occurred within the same physical space (a plus maze) without any physical cue to indicate the correct strategy in a given trial, this scenario critically involves disambiguation of task demands and presumably pattern separation. Performance of the two tasks induced zif268 expression in distinct populations of granule cells within the suprapyramidal but not the infrapyramidal blade of the DG. Repeated performance of the same task (i.e., two response-task trials or two place-task trials), however, elicited zif268 expression within a single subset of the granule cell population. This differential transcription pattern shows that the retrieval of different behavioral strategies or mnemonic demands recruit distinct ensembles of granule cells, possibly to prevent interference between memories of events occurring within the same physical space to permit the selection of appropriate responses.
authors.affiliation: Wilfrid Laurier University, Waterloo, Ontario N2L 3C5, Canada.
authors.forename: Elham
authors.initials: E
authors.lastname: Satvat
authors.forename: Brandy
authors.initials: B
authors.lastname: Schmidt
authors.forename: Melissa
authors.initials: M
authors.lastname: Argraves
authors.forename: Diano F
authors.initials: DF
authors.lastname: Marrone
authors.forename: Etan J
authors.initials: EJ
authors.lastname: Markus
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D003463:Cues; D018891:Dentate Gyrus / Q000166:cytology / Q000378:metabolism*; D051766:Early Growth Response Protein 1 / Q000235:genetics / Q000378:metabolism*; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D018782:Maze Learning / Q000502:physiology*; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344; D012193:Reversal Learning / Q000502:physiology; D013037:Spatial Behavior / Q000502:physiology*
chemical_list: D051766:Early Growth Response Protein 1; C486110:Egr1 protein, rat; D012333:RNA, Messenger