Neuroscience Laboratory, Institute for Medical Sciences and Neuroscience Graduate Program, Ajou University School of Medicine, Suwon 443-721, Korea.
J Neurosci. 2013 Jan 2;33(1):52-63. doi: 10.1523/JNEUROSCI.2422-12.2013.
The cortico-basal ganglia network has been proposed to consist of parallel loops serving distinct functions. However, it is still uncertain how the content of processed information varies across different loops and how it is related to the functions of each loop. We investigated this issue by comparing neuronal activity in the dorsolateral (sensorimotor) and dorsomedial (associative) striatum, which have been linked to habitual and goal-directed action selection, respectively, in rats performing a dynamic foraging task. Both regions conveyed significant neural signals for the animal's goal choice and its outcome. Moreover, both regions conveyed similar levels of neural signals for action value before the animal's goal choice and chosen value after the outcome of the animal's choice was revealed. However, a striking difference was found in the persistence of neural signals for the animal's chosen action. Signals for the animal's goal choice persisted in the dorsomedial striatum until the outcome of the animal's next goal choice was revealed, whereas they dissipated rapidly in the dorsolateral striatum. These persistent choice signals might be used for causally linking temporally discontiguous responses and their outcomes in the dorsomedial striatum, thereby contributing to its role in goal-directed action selection.
皮质-基底神经节网络被提议由服务于不同功能的平行环路组成。然而,目前尚不清楚处理的信息内容如何在不同的环路中变化,以及它与每个环路的功能有何关系。我们通过比较在执行动态觅食任务的大鼠的背外侧(感觉运动)和背内侧(联想)纹状体中的神经元活动来研究这个问题。这两个区域都对动物的目标选择及其结果传递了显著的神经信号。此外,在动物的目标选择之前,这两个区域都传递了类似水平的动作值的神经信号,并且在动物的选择结果之后传递了选择的值。然而,在动物选择的动作的神经信号的持久性方面发现了一个显著的差异。动物的目标选择的信号在背内侧纹状体中持续存在,直到揭示动物的下一个目标选择的结果,而在背外侧纹状体中则迅速消散。这些持续的选择信号可能用于在背内侧纹状体中因果地连接时间上不连续的反应及其结果,从而有助于其在目标导向的动作选择中的作用。