Perceptual and Cognitive Processes in Identification and Categorization

9514427阿什比这项研究将研究复杂知觉刺激的识别和分类中使用的知觉和认知过程。该研究项目将开发和测试一种新的理论，该理论假设类别学习是两个独立的分类系统之间的竞争。一个系统使用可以用语言描述的规则，并且可以接触到意识(即，语言系统)，而另一个系统可以学习无法用语言描述的规则(即，隐含系统)。这一理论将在三个不同的层面上进行描述。神经心理学版本将详细描述不同系统使用的主要大脑区域和神经路径，以及调节系统之间竞争的神经路径。此外，还将对该理论进行两种不同的数学描述。其中一个将提供该理论预测的当人们学习新类别时应该发生的动态行为的全球水平描述。另一个将提供更详细的描述，可用于预测逐个试验类别的学习行为。将进行许多实验来检验该理论的新颖预测。除了对正常成人的类别学习做出预测外，该理论还对儿童、老年人、患有严重抑郁症和基底神经节疾病(例如帕金森氏症和亨廷顿病)的患者以及非人类动物进行了具体预测。这项研究将提高我们对认知过程中最基本和最重要的过程之一--范畴化的理解。它还有可能增加我们对几种主要疾病和障碍的认知影响的理解，以及认知如何受到正常衰老过程的影响。这个项目将把广泛的实验与理论研究结合起来，这些研究在很大程度上依赖于数学建模技术和神经科学的最新发现。***

9514427 ASHBY This research will investigate the perceptual and cognitive processes used in the identification and categorization of complex perceptual stimuli. The research program will develop and test a new theory that assumes category learning is a competition between two separate categorization systems. One system uses rules that can be described verbally and has access to consciousness (i.e., the verbal system), whereas the other can learn rules that are impossible to describe verbally (i.e., the implicit system). The theory will be described at three different levels. A neuropsychological version will provide a detailed description of the major brain areas and neural pathways used by the separate systems and that mediate the competition between the systems. In addition, two separate mathematical descriptions of the theory will be developed. One will provide a global level description of the dynamical behavior that the theory predicts should occur when people learn new categories. The other will provide a more detailed description that can be used to predict trial-by-trial category learning behavior. Many experiments will be conducted to test novel predictions of the theory. In addition to making predictions about category learning in normal human adults, the theory also makes specific predictions for children, the elderly, patients suffering from major depression and from diseases of the basal ganglia (e.g., Parkinson's and Huntington's disease), and for nonhuman animals. This research will improve our understanding of one of the most basic and important of cognitive processes, namely categorization. It also has the potential to increase our understanding of the cognitive effects of several major diseases and disorders, and of how cognition is affected by normal aging processes. This project will combine extensive experimentation with theoretical investigations that rely heavily on mathematical modeling techniques and recent discoveries in th e neurosciences. ***