Functional Neuroimaging of Strategic Retrieval Processes

描述（由申请人提供）：情景记忆主要依赖于生成检索计划、检索探针的精心处理、干扰的解决以及对决策标准的记忆充分性的监测。虽然前额叶皮层（PFC）是这些机制的有利候选人，这些机制的区域和半球定位尚不清楚。使用一个组件-过程模型，我们将：（1）确定是否左前额叶皮层是关键参与制定情景检索计划。最近对比上下文和项目记忆的研究一致地识别了左前额叶皮层，并表明活动不依赖于成功，这表明检索上下文信息的意图至关重要。在这里，我们打算分离线索/问题和探针依赖的活动，并确定这些地区是否响应非语言化的探针在基于上下文的检索需求。(2)进行基于决策理论的记忆决策标准操作。通过操纵决策标准的数量、位置和质量，我们将把执行决策规则的关键PFC区域隔离到记忆内容。(3)研究情景提取过程中大脑半球的不对称性。最近的证据表明，在PFC（特别是背侧和极地）与左区与上下文相关的具体来源的归属，和同源的右PFC区域显示相对增加，在判断项目的近度或频率，这是潜在的全球熟悉性评估的基础上，半球的不对称性。通过直接对比近因，频率和上下文检索匹配的材料内的主题，我们将测试半球是否参与了记忆检索的根本不同的方面，超越早期的结构，如“努力”或“困难”。健康老龄化和神经系统疾病期间的神经系统变化（例如，阿尔茨海默氏痴呆症、轻度认知障碍、创伤性脑损伤）严重影响记忆表现。然而，由于调节记忆表达的控制或决策过程知之甚少，行为障碍通常可能是由于表征或存储记忆证据的系统、负责对该内容施加决策的系统或两者的某种组合受到损害而导致的。因此，确定PFC区域如何正常调节记忆内容转化为决策或行动，对于理解上述人群的记忆表现下降至关重要。

DESCRIPTION (provided by applicant): Episodic remembering critically relies on the generation retrieval plans, the elaborative processing of retrieval probes, the resolution of interference, and the monitoring of the sufficiency of memory with respect to decision criteria. Although prefrontal cortex (PFC) is the favored candidate for these mechanisms, regional and hemispheric localization for these mechanisms is unclear. Using a component-process model we will: (1) Determine whether left PFC is critically involved in formulating episodic retrieval plans. Recent research contrasting context and item memory have consistently identified left PFC and indicated that activity is not dependent on success, suggesting that it is the intent to retrieve contextual information that is critical. Here we intend to separate cue/question and probe dependent activity and determine whether these regions respond to non-verbalizable probes during contextually based retrieval demands. (2) Conduct Decision Theory based manipulations of memory decision criteria. By manipulating the number, location, and quality of decision criteria we will isolate PFC regions critical for implementing decision rules to memory content. (3) Investigate hemispheric asymmetries during episodic retrieval. Recent evidence suggests hemispheric asymmetries in PFC (particularly dorsal and polar) with left regions associated with contextually specific source attribution, and homologous right PFC regions showing relative increases during judgments of item recency or frequency, which are potentially based on global familiarity assessment. By directly contrasting recency, frequency, and context retrieval for matched materials within subjects, we will test whether the hemispheres are involved in fundamentally different aspects of memory retrieval, advancing beyond earlier constructs such as "effort" or "difficulty". Neurological changes during healthy aging and neurological disorders (e.g., Alzheimer's Dementia, Mild Cognitive Impairment, Traumatic Brain Injury) severely impact memory performance. However, because the control or decision processes regulating memory expression are poorly understood, behavioral impairments could often result from damage to systems that represent or store memory evidence, systems responsible for imposing decisions upon that content, or some combination of the 2. Determining how PFC regions normally regulate the translation of memory content into decisions or actions is therefore critical in understanding the memory performance decline in the above populations.