RECOGNITION MEMORY: NEURAL CORRELATES OF ITEM MEMORY STRENGTH

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 识别记忆决策可以基于由测试探头引起的感知记忆强度。一个被认为影响记忆强度的因素是被研究的刺激和测试探头之间的知觉相似程度。对学习-测试知觉相似性的系统操作可能会对识别决策的行为和神经基础提供杠杆作用。在本实验中，我们改变了被研究项目和测试探针之间的知觉相似程度，以检验相似性对知觉记忆强度的影响，以及对提取时记忆强度的神经关联的影响。在研究中，在执行尺寸判断任务时，对形状进行了编码。在测试中，功能磁共振成像(FMRI)测量了受试者对三种类型的测试探针做出记忆决定时的神经反应，这些测试探针与研究项目的相似性不同：研究的形状，研究和未研究的形状之间的变化的未研究的形状，以及未研究的形状。受试者表示，他们是否认出了这个形状是旧的还是新的。

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. Recognition memory decisions can be based on the perceived memory strength elicited by a test probe. One factor that is posited to influence memory strength is the degree of perceptual similarity between studied stimuli and test probes. Systematic manipulation of study-test perceptual similarity may provide leverage on the behavioral and neural bases of recognition decisions. In this experiment, we parametrically varied the degree of perceptual similarity between studied items and test probes to examine the impact of similarity on perceived memory strength and on the neural correlates of memory strength at retrieval. At study, shapes were encoded during performance of a size judgment task. At test, functional MRI (fMRI) measured neural responses as subjects made memory decisions about three types of test probes that varied in similarity to studied items: studied shapes, unstudied shapes that were morphs between a studied and an unstudied shape, and unstudied shapes. Subjects indicated whether they recognized the shape as old or new.