Circuit simulation of working memory control by dopamine

我对多巴胺控制工作记忆做了理论分析和计算机模拟。建立了新的模型，提出了新的理论。该研究致力于D1和D2受体的功能。首先，多巴胺是如何通过激活D1受体来改变工作记忆表征的稳定性的。这项研究表明，多巴胺不仅改变了工作记忆表征的鲁棒性，正如以前所建议的那样，但改变了基本的认知操作，以便可以执行各种操作。其次，通过分析多巴胺能调节系统的动力学特征，阐明了多巴胺能系统在认知控制中的作用。动态建议有不同的特性，取决于细胞外多巴胺浓度在前额叶皮层。最后，笔者提出了一个新的精神分裂症理论，即“精神分裂症稳定性理论”。该理论指出，认知操作的网络在脑功能减退的情况下往往是不稳定的。这一理论不仅可以解释精神分裂症患者在执行认知任务时前额叶皮层多巴胺浓度的降低，而且可以解释功能成像研究中经常观察到的前额叶皮层异常激活。这一理论应该应用于精神病学研究。

I did theoretical analysis and computer simulations of working memory control by dopamine. New models are constructed and a new theory is proposed. The study is devoted to the functions of D1 and D2 receptors. First, how dopamine changes the stability of working memory representation via D1 receptor activation has been explored. This study suggests that dopamine do not only change the robustness of working memory representation, as was suggested previously, but alter fundamental cognitive operations so that various kinds of operations can be performed. Second, by analyzing the dynamical characteristics of the dopaminergic modulatory system, this study elucidated the functions of the dopaminergic system regarding cognitive control. The dynamics is suggested to have different characteristics depending on the extracelullar dopamine concentration in the prefrontal cortex. Finally, I propose a new theory on schizophrenia, that is "the stability theory of schizophrenia". This theory states that the network for cognitive operations tends to be unstable under hypoglutamatergic conditions. This theory can account for not only the decrement of dopamine concentration in the prefrontal cortex but abnormal activation of the prefrontal cortex, which has often been observed by functional imaging studies while the patients with schizophrenia performed cognitive tasks. This theory should be applied to psychiatric research.