Neural organization of learning and thought in the cortico-basal ganglia system

我们在2002年至2004年的三年期间进行了以下两个由赠款支持的核心项目。来自CM/PF复合体的丘脑-纹状体投射的功能作用：我们证明了CM/PF丘脑中的神经元向纹状体传递关于具有生物学意义的、吸引注意的外部事件的信息(MatSumoto等人，2001；Minamimoto等人，2002)。基于我们最近对基底节和丘脑的发现，我们提出了一个网络模型，即皮质-基底节环作为基于奖赏的决策和行动选择，而丘脑-纹状体投射起到补充基于奖赏的决策和行动偏向的作用(Kimura等人)。2004年)。该模型得到了实验上的支持(Minamimoto等人，2005)。反向依赖的动作选择和学习：我们证明纹状投射神经元编码关于执行顺序运动任务的程序的信息(Kimura等人，2003；上田等人，2003)。通过对人脑的功能磁共振成像研究，我们发现尾状核在基于奖赏的决策策略学习中起着关键作用，以选择价值更高的行动(Haruno等人)。2004年)。通过记录猕猴执行基于奖赏的决策任务的纹状神经元活动，我们最近发现，纹状投射神经元编码动作特定的奖赏价值(Samejima等人提交)。

We conducted the following two core projects supported by the grant for the three-year term from 2002 to 2004.Functional roles of the thalamo-striate projections originating from CM/Pf complex: We demonstrated that the neurons in the CM/Pf thalamus convey information about biologically significant, attention-drawing external events to the striatum (Matsumoto et al., 2001; Minamimoto et al., 2002). Based on our recent findings on the basal ganglia and thalamus, we proposed a network model that the cortico-basal ganglia loops work as reward-based decision and action selection, while the thalamo-striate projection plays complementary roles to the reward-based decision and action bias (Kimura et al. 2004). The proposed model was supported experimentally (Minamimoto et al., 2005).Reward-dependent action selection and learning: We demonstrated that the striate projection neurons encode information about procedure of performing sequential movement task (Kimura et al., 2003; Ueda et al., 2003). Using functional MRI imaging study of human brain, we showed that the caudate nucleus play a critical roles in reward-based learning of decision strategy to select higher-valued action (Haruno et al. 2004). By recording striate neuron activity of macaque monkeys performing reward-based decision task, we recently found that the striate projection neurons encode action-specific reward value (Samejima et al., submitted).