A neurocomputational model of dopamine and prefrontal-striatal interactions during multicue category learning by Parkinson patients.
A neurocomputational model of dopamine and prefrontal-striatal interactions during multicue category learning by Parkinson patients.
复制标题
帕金森患者多线索类别学习期间多巴胺和前额叶-纹状体相互作用的神经计算模型。
DOI：
10.1162/jocn.2010.21420
复制
发表时间：
2011
影响因子：
3.2
通讯作者：
Gluck,MarkA
中科院分区：
文献类型：
--
作者：
Moustafa,AhmedA;Gluck,MarkA
Most existing models of dopamine and learning in Parkinson disease (PD) focus on simulating the role of basal ganglia dopamine in reinforcement learning. Much data argue, however, for a critical role for prefrontal cortex (PFC) dopamine in stimulus selection in attentional learning. Here, we present a new computational model that simulates performance in multicue category learning, such as the “weather prediction” task. The model addresses how PD and dopamine medications affect stimulus selection processes, which mediate reinforcement learning. In this model, PFC dopamine is key for attentional learning, whereas basal ganglia dopamine, consistent with other models, is key for reinforcement and motor learning. The model assumes that competitive dynamics among PFC neurons is the neural mechanism underlying stimulus selection with limited attentional resources, whereas competitive dynamics among striatal neurons is the neural mechanism underlying action selection. According to our model, PD is associated with decreased phasic and tonic dopamine levels in both PFC and basal ganglia. We assume that dopamine medications increase dopamine levels in both the basal ganglia and PFC, which, in turn, increase tonic dopamine levels but decrease the magnitude of phasic dopamine signaling in these brain structures. Increase of tonic dopamine levels in the simulated PFC enhances attentional shifting performance. The model provides a mechanistic account for several phenomena, including (a) medicated PD patients are more impaired at multicue probabilistic category learning than unmedicated patients and (b) medicated PD patients opt out of reversal when there are alternative and redundant cue dimensions.
