Costa Rui M
Section on In Vivo Neural Function, Laboratory for Integrative Neuroscience, NIAAA, NIH, Bethesda, MD 20852-9411, USA.
Ann N Y Acad Sci. 2007 May;1104:172-91. doi: 10.1196/annals.1390.015. Epub 2007 Apr 13.
Reentrant corticobasal ganglia circuits are important for voluntary action and for action selection. In vivo and ex vivo studies show that these circuits can exhibit a plethora of short- and long-lasting plastic changes. Convergent evidence at the molecular, cellular, and circuit levels indicates that corticostriatal circuits are involved in the acquisition and automatization of novel actions. There is strong evidence that activity in corticostriatal circuits changes during the learning of novel actions, but the plastic changes observed during the early stages of learning a novel action are different than those observed after extensive training. A variety of studies indicate that the neural mechanisms and the corticostriatal subcircuits involved in the initial acquisition of actions and skills differ from those involved in their automatization or in the formation of habits. Dopamine, a critical modulator of short- and long-term plasticity in corticostriatal circuits, is differentially involved in early and late stages of action learning. Changes in dopaminergic transmission have several concomitant effects in corticostriatal function, which may be important for action selection and action learning. These diverse effects may subserve different roles for dopamine in reinforcement and action learning.
折返性皮质-基底神经节环路对随意动作和动作选择很重要。体内和体外研究表明，这些环路可表现出大量短期和长期的可塑性变化。分子、细胞和环路水平的汇聚证据表明，皮质-纹状体环路参与新动作的习得和自动化。有强有力的证据表明，在学习新动作过程中皮质-纹状体环路的活动会发生变化，但在学习新动作早期阶段观察到的可塑性变化与广泛训练后观察到的不同。各种研究表明，参与动作和技能初始习得的神经机制及皮质-纹状体子环路与参与其自动化或习惯形成的不同。多巴胺是皮质-纹状体环路短期和长期可塑性的关键调节因子，在动作学习的早期和晚期阶段发挥不同作用。多巴胺能传递的变化在皮质-纹状体功能上有多种伴随效应，这可能对动作选择和动作学习很重要。这些不同的效应可能使多巴胺在强化和动作学习中发挥不同作用。
