著者

永野 茜 奥村 紗音美 青山 謙二郎 上北 朋子

出版者

公益社団法人 日本心理学会

雑誌

心理学研究 (ISSN:00215236)

巻号頁・発行日

vol.86, no.6, pp.603-609, 2016

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Previous studies have reported that lesions of the orbitofrontal cortex (OFC) in rats induce impulsive choices in delayed reinforcement tasks.<b> </b>However, some studies have suggested that the OFC is not related to impulsivity but instead to compulsivity.<b> </b>In this study, we investigated the effects of OFC lesions on choice in a T-maze.<b> </b>First, 14 rats were trained to discriminate spatially between a high-reward arm with a delay of 15 seconds and a low-reward arm without a delay.<b> </b>The high-reward arm contained 10 food pellets, whereas the low-reward arm contained only one pellet.<b> </b>In the presurgery test, all rats chose the high-reward arm in most trials.<b> </b>In the postsurgery test, both OFC lesioned (<i>n</i> = 7) and control (sham-lesioned and intact; <i>n</i> = 7) rats continued to choose the high-reward arm in most trials.<b> </b>Following the postsurgery test, the high- and low-reward arms were reversed.<b> </b>In the reversal test, OFC lesioned rats made significantly fewer high-reward choices than did control rats.<b> </b>These results indicate that OFC lesions induced compulsive choices rather than impulsive choices.