NEURAL MECHANISMS OF VISUAL PERCEPTION

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者的研究机构。 我们提出了一些实验来检验有关大脑决策能力的神经机制的假设。我们的实验解决了大脑将视觉皮层神经元代表的感觉信息转换为决定这些信息对计划行为的意义的机制。我们发现，猕猴的联合皮层神经元代表了这种选择和反对另一种选择的证据的积累。今年，我们证明了解释选择和决策时间的机制也解释了与选择相关的信心程度。我们开发了一种“决策后下注”技术，以确定猴子做出的决策的确定性（Kiani & Shadlen，2009）。在与Wolpert教授（英国剑桥）的合作中，我们证实了在非人类灵长类动物中阐明的决策机制也解释了人类决策者的行为。有趣的是，它解释了在最初的承诺之后对一些决定的修改，也就是说，一种动摇或改变主意的形式（Resulaj等人，2009）。 决策弥合了感觉和行为之间的差距。几乎所有的非反射行为都需要大脑利用其感觉皮层来指导未来的行为。因此，我们所研究的简单决策的神经机制可能有助于深入了解更复杂的认知策略。我们的实验最终为影响感知，计划和推理的精神障碍的原因和治疗提供了新的见解。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. We proposed experiments that test hypotheses about the neural mechanisms that underlie the brain's ability to make decisions. Our experiments address the mechanism used by the brain to convert sensory information represented by neurons in the visual cortex to a decision about what this information means for purposes of planning behavior. We showed that neurons in the association cortex of the macaque represent the accumulation of this evidence for one choice and against an alternative. This year, we demonstrated that the mechanism that explains choice and decision time also explains the degree of confidence associated with a choice. We developed a "post-decision wagering" technique to ascertain certainty in the decisions rendered by monkeys (Kiani & Shadlen, 2009). A collaboration with Prof. Wolpert (Cambridge, UK) we confirmed that the mechanism for decision making elucidated in nonhuman primates also explains the behavior of human decision makers. Interestingly, it explains the revision of some decisions after an initial commitment, that is, a form of vacillation or change of mind (Resulaj et al, 2009). Decision-making bridges the gap between sensation and behavior. Nearly all non-reflexive behaviors require the brain to draw upon its sensory cortex to guide future behavior. Thus, the neural mechanisms for the simple decisions we study are likely to lend insight into more complex cognitive strategies. Our experiments ultimately furnish new insights into the causes and treatments of mental disorders affecting perception, planning and reasoning.