The Perirhinal Cortex and Implicit Memory

嗅周皮层和内隐记忆

• 批准号: 8391795
• 负责人: Wei-Chun Wang
• 金额: $ 2.88万
• 依托单位: UNIVERSITY OF CALIFORNIA AT DAVIS
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-01-01 至 2013-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8391795
• 关键词: Affect; Alzheimer' s Disease; Awareness; Brain; Complex; Diagnosis; Discrimination; Disease; Epilepsy; Event; Exhibits; Familiarity; Free Association; Functional Magnetic Resonance Imaging; Hippocampus (Brain); Human; Impairment; Intention; Intervention; Left; Life; Lobectomy; Magnetic Resonance Imaging; Manuals; Measures; Medial; Memory; Memory Disorders; Memory impairment; Mental Depression; Mental disorders; Modeling; Morphologic artifacts; Movement; Participant; Patients; Phase; Play; Process; Production; Quality of life; Recruitment Activity; Resolution; Retrieval; Role; Scanning; Schizophrenia; Speech; Stroke; Symptoms; Temporal Lobe; Testing; Work; base; design; experience; implicit memory; insight; interest; long term memory; memory encoding; memory retrieval; nervous system disorder; novel; patient population; research study; theories; young adult

Many theories of human long term memory assume that explicit memory for prior events relies on the medial temporal lobes (MTLs) and its subregions. In contrast, implicit memory, measured in tasks where experience with a prior item facilitates the subsequent identification or production of that item, is thought to rely on cortical regions outside of the MTL. However, it has recently been hypothesized that the perirhinal cortex, a region within the MTL, holds high level conceptual and perceptual representations irrespective of awareness or intention. In one recent study, we provided evidence that the perirhinal cortex is sensitive to certain forms of implicit memory. We demonstrated that amnesic stroke and temporal lobectomy patients exhibited impaired conceptual implicit memory, and in a separate experiment showed that perirhinal activations at encoding predicted subsequent conceptual implicit memory. The experiments proposed here seek to extend these previous findings. In the first experiment, a novel paradigm that measures both conceptual implicit memory and explicit familiarity-based recognition will be used to assess the role of the perirhinal cortex in these two tasks. Participants will be scanned during recognition and free association memory tasks that measure familiarity and conceptual implicit memory, respectively. In the second experiment we will test the hypothesis that sufficiently complex perceptual discriminations will recruit the perirhinal cortex during both the encoding and retrieval phases of a perceptual implicit memory task. Both experiments will utilize high-resolution fMRI and region of interest alignment derived from manual MRI brain tracing. Moreover, for the first experiment we will develop a unique fMRI sequence designed to counteract movement artifacts intrinsic to overt speech. Understanding the conditions under which the perirhinal cortex processes and represents conceptual and perceptual information is critical to understanding the role of the MTLs in long term memory and beyond. The insights from these studies can be applied to diagnose, understand, and treat memory deficits and mental disorders that adversely affect memory.

许多关于人类长期记忆的理论认为，对先前事件的外显记忆依赖于内侧颞叶及其子区域。相比之下，内隐记忆则被认为依赖于颞叶外的皮质区域。内隐记忆是在对先前项目的经验有助于随后对该项目的识别或产生的任务中测量的。然而，最近有一种假设认为，无论意识或意图如何，MTL内的一个区域——鼻周皮层都具有高水平的概念和知觉表征。在最近的一项研究中，我们提供的证据表明，周围皮层对某些形式的内隐记忆很敏感。我们证明了失忆性中风和颞叶切除术患者表现出概念内隐记忆受损，并在一个单独的实验中表明，在编码上的周围皮层激活预测了随后的概念内隐记忆。