title: Role of hippocampus in polymodal-cue guided tasks in rats.
abstract: To examine how signals from different sensory modalities are integrated to generate an appropriate goal-oriented behavior, we trained rats in an eight-arm radial maze to visit a cue arm provided with intramaze cues from different sensory modalities, i.e. visual, tactile and auditory, in order to obtain a reward. When the same rats were then examined on test trials in which the cue arm contained one of the stimuli that the animals were trained with (i.e. light, sound or rough sheet), they showed a significant impairment with respect to the performance on the polymodal-cue task. The contribution of the dorsal hippocampus to the acquisition and retention of polymodal-cue guided task was also examined. We found that rats with dorsal hippocampal lesions before training showed a significant deficit in the acquisition of polymodal-cue oriented task that improved with overtraining. The selective lesion of the dorsal hippocampus after training disrupted memory retention, but the animals' performance improved following retraining of the polymodal task. All hippocampal lesioned rats displayed an impaired performance on the unimodal test. These findings suggest that the dorsal hippocampus contributes to the processing of multimodal sensory information for the associative memory formation and consolidation.
authors.affiliation: Department of Pharmacy, University of Naples "Federico II", 80131 Naples, Italy. Electronic address: maria.miniaci@unina.it.
authors.forename: Maria Concetta
authors.initials: MC
authors.lastname: Miniaci
authors.affiliation: Department of Pharmacy, University of Naples "Federico II", 80131 Naples, Italy.
authors.forename: Pellegrino
authors.initials: P
authors.lastname: Lippiello
authors.affiliation: Department of Experimental Medicine, Second University of Naples, 80138 Naples, Italy.
authors.forename: Marcellino
authors.initials: M
authors.lastname: Monda
authors.affiliation: Department of Pharmacy, University of Naples "Federico II", 80131 Naples, Italy.
authors.forename: Pietro
authors.initials: P
authors.lastname: Scotto
mesh_terms: D000818:Animals; D001245:Association Learning / Q000502:physiology*; D003463:Cues; D006624:Hippocampus / Q000502:physiology*; D008297:Male; D018782:Maze Learning / Q000502:physiology; D008568:Memory / Q000502:physiology*; D051381:Rats; D020318:Rats, Long-Evans; D012201:Reward
keywords: Dorsal hippocampus; Electrolytic lesions; Learning; Memory; Polymodal cues