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Neuron:大脑从成功经验中学到更多
来源 新华社 2009-8-2 14:47:45
Neuron:大脑从成功经验中学到更多
一些人认为,人们总是可以从失败中学到东西,但大脑的工作原理似乎并非如此。美国一项最新研究认为,失败的经历几乎对大脑不起作用,脑细胞从成功的经验中学到更多东西。
美国麻省理工学院的研究人员根据实验中动物脑细胞的不同反应得出以上结论。研究人员创设了一种独特的“快照”系统,以反映脑细胞的学习过程,在提供正确和错误行为的信息后,实时拍下单个脑细胞的反应。
研究人员在一份声明中说:“脑细胞可以记录近期的行为是否成功。当某一行为成功时,脑细胞会针对所学内容进行更加微细的调整。而当失败发生时,脑部几乎没有发生任何变化,行为也没有获得改善。”
这项研究成果刊登在美国《神经元》月刊上。(生物谷)
(英文: )
Neuron, Volume 63, Issue 2, 244-253, 30 July 2009 doi:10.1016/j.neuron.2009.06.019
Learning Substrates in the Primate Prefrontal Cortex and Striatum: Sustained Activity Related to Successful Actions
Mark H. Histed1,2,4,,,Anitha Pasupathy1,2,3andEarl K. Miller1
1 The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
2 These authors contributed equally to this work
3 Present address: Department of Biological Structure, University of Washington, Seattle, WA 98195, USA
4 Present address: Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
Learning from experience requires knowing whether a past action resulted in a desired outcome. The prefrontal cortex and basal ganglia are thought to play key roles in such learning of arbitrary stimulus-response associations. Previous studies have found neural activity in these areas, similar to dopaminergic neurons' signals, that transiently reflect whethera response is correct or incorrect. However, it is unclear how this transient activity, which fades in under a second, influences actions that occur much later. Here, we report that single neurons in both areas show sustained, persistent outcome-related responses. Moreover, single behavioral outcomes influence future neural activity and behavior: behavioral responses are more often correct and single neurons more accurately discriminate between the possible responses when the previous response was correct. These long-lasting signals about trial outcome provide a way to link one action to the next and may allow reward signals to be combined over time to implement successful learning.
[ 本帖最后由 顾汉现 于 2009-8-4 21:05 编辑 ] |
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