文章基本信息

标题：Retrospective and prospective responses arising in a modeled hippocampus during maze navigation by a brain-based device
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作者：Jason G. Fleischer ; Joseph A. Gally ; Gerald M. Edelman 等
期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2007
卷号：104
期号：9
页码：3556-3561
DOI：10.1073/pnas.0611571104
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Recent recordings of place field activity in rodent hippocampus have revealed correlates of current, recent past, and imminent future events in spatial memory tasks. To analyze these properties, we used a brain-based device, Darwin XI, that incorporated a detailed model of medial temporal structures shaped by experience-dependent synaptic activity. Darwin XI was tested on a plus maze in which it approached a goal arm from different start arms. In the task, a journey corresponded to the route from a particular starting point to a particular goal. During maze navigation, the device developed place-dependent responses in its simulated hippocampus. Journey-dependent place fields, whose activity differed in different journeys through the same maze arm, were found in the recordings of simulated CA1 neuronal units. We also found an approximately equal number of journey-independent place fields. The journey-dependent responses were either retrospective, where activity was present in the goal arm, or prospective, where activity was present in the start arm. Detailed analysis of network dynamics of the neural simulation during behavior revealed that many different neural pathways could stimulate any single CA1 unit. That analysis also revealed that place activity was driven more by hippocampal and entorhinal cortical influences than by sensory cortical input. Moreover, journey-dependent activity was driven more strongly by hippocampal influence than journey-independent activity.
关键词：episodic memory ; hippocampal anatomy ; place fields ; spatial learning ; backtrace