Servan-Schreiber D, Bruno R M, Carter C S, Cohen J D
Department of Psychiatry, University of Pittsburgh, Pennsylvania, USA.
Biol Psychiatry. 1998 May 15;43(10):713-22. doi: 10.1016/s0006-3223(97)00448-4.
Dopamine affects neural information processing, cognition, and behavior; however, the mechanisms through which these three levels of function are affected have remained unspecified. We present a parallel-distributed processing model of dopamine effects on neural ensembles that accounts for effects on human performance in a selective attention task.
Task performance is stimulated using principles and mechanisms that capture salient aspects of information processing in neural ensembles. Dopamine effects are simulated as a change in gain of neural assemblies in the area of release.
The model leads to different predictions as a function of the hypothesized location of dopamine effects. Motor system effects are simulated as a change in gain over the response layer of the model. This induces speeding of reaction times but an impairment of accuracy. Cognitive attentional effects are simulated as a change in gain over the attention layer. This induces a speeding of reaction times and an improvement of accuracy, especially at very fast reaction times and when processing of the stimulus requires selective attention.
A computer simulation using widely accepted principles of processing in neural ensembles can account for reaction time distributions and time-accuracy curves in a selective attention task. The simulation can be used to generate predictions about the effects of dopamine agonists on performance. An empirical study evaluating these predictions is described in a companion paper.
多巴胺会影响神经信息处理、认知和行为；然而，这三个功能层面受影响的机制仍不明确。我们提出了一个多巴胺对神经集群影响的并行分布式处理模型，该模型解释了其对选择性注意任务中人类表现的影响。
利用捕捉神经集群中信息处理显著方面的原理和机制来刺激任务表现。将多巴胺的影响模拟为释放区域神经组件增益的变化。
根据多巴胺影响的假设位置，该模型会产生不同的预测。运动系统的影响被模拟为模型响应层增益的变化。这会导致反应时间加快，但准确性受损。认知注意的影响被模拟为注意层增益的变化。这会导致反应时间加快且准确性提高，尤其是在非常快的反应时间以及刺激处理需要选择性注意时。
使用神经集群中广泛接受的处理原理进行的计算机模拟可以解释选择性注意任务中的反应时间分布和时间准确性曲线。该模拟可用于生成关于多巴胺激动剂对表现影响的预测。一篇配套论文中描述了一项评估这些预测的实证研究。
