title: Evidences of the role of the rodent hippocampus in the non-spatial recognition memory.
abstract: The hippocampus is a key region responsible for processing spatial information. However, the role of the hippocampus in non-spatial recognition memory is still controversial. In the present study, we performed hippocampal lesioning to address this controversy. The hippocampi of mice were disrupted with bilateral cytotoxic lesions, and standard object recognition (non-spatial) and object location recognition (spatial) were tested. In the habituation period, mice with hippocampal lesions needed a significantly longer time to fully habituate to the test box. Interestingly, after 4 days of habituation (insufficient habituation), the recognition index was similar in the sham and hippocampal lesion groups. However, exploration time was significantly shorter in mice with hippocampal lesions compared with that in control mice. Interestingly, if mice were subjected to a 10-days-long period of habituation (full habituation), the recognition index was significantly lower in mice with hippocampal lesions compared with that in control mice; however, total exploration time was similar in both groups. Furthermore, the object recognition test after full habituation occluded hippocampal long-term potentiation, a cellular model of memory. These results indicate that sufficient habituation is required to observe the effects of hippocampal lesions on object recognition memory.
authors.affiliation: School of Clinical Sciences, Faculty of Medicine and Dentistry, University of Bristol, Bristol, UK.
authors.forename: Jee Hyun
authors.initials: JH
authors.lastname: Yi
authors.affiliation: Department of Medicinal Biotechnology, College of Health Sciences, Dong-A University, Busan 604-714, Republic of Korea; Dong-A Anti-aging Research Center, Dong-A University, Busan 604-714, Republic of Korea.
authors.forename: Hye Jin
authors.initials: HJ
authors.lastname: Park
authors.affiliation: Chonnam-Bristol Frontier Laboratory, Biomedical Research Institute, Chonnam National University Hospital, Jebong-ro, Gwangju 501-757, Republic of Korea.
authors.forename: Byeong C
authors.initials: BC
authors.lastname: Kim
authors.affiliation: Department of Medicinal Biotechnology, College of Health Sciences, Dong-A University, Busan 604-714, Republic of Korea; Dong-A Anti-aging Research Center, Dong-A University, Busan 604-714, Republic of Korea. Electronic address: mose79@dau.ac.kr.
authors.forename: Dong Hyun
authors.initials: DH
authors.lastname: Kim
authors.affiliation: Department of Life and Nanopharmaceutical Science, College of Pharmacy, Kyung Hee University, 1 Hoeki-dong, Dongdaemoon-Gu, Seoul 130-701, Republic of Korea; Oriental Pharmaceutical Science, College of Pharmacy, Kyung Hee University, 1 Hoeki-dong, Dongdaemoon-Gu, Seoul 130-701, Republic of Korea; Kyung Hee East-West Pharmaceutical Research Institute, College of Pharmacy, Kyung Hee University, 1 Hoeki-dong, Dongdaemoon-Gu, Seoul 130-701, Republic of Korea. Electronic address: jhryu63@khu.ac.kr.
authors.forename: Jong Hoon
authors.initials: JH
authors.lastname: Ryu
mesh_terms: D000818:Animals; D005106:Exploratory Behavior / Q000502:physiology; D006185:Habituation, Psychophysiologic / Q000502:physiology; D006624:Hippocampus / Q000502:physiology* / Q000503:physiopathology; D007051:Ibotenic Acid; D017774:Long-Term Potentiation / Q000502:physiology; D008297:Male; D008813:Mice, Inbred ICR; D009483:Neuropsychological Tests; D021641:Recognition, Psychology / Q000502:physiology*; D065852:Spatial Memory / Q000502:physiology; D046509:Tissue Culture Techniques
chemical_list: D007051:Ibotenic Acid
keywords: Habituation; Hippocampus; Long-term potentiation; Recognition memory