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，检索探针的详细处理，干扰的解决，以及与决策标准相关的记忆充分性的监测。虽然前额叶皮层（PFC）是这些机制的首选候选者，但这些机制的区域和半球定位尚不清楚。使用组件-过程模型，我们将：(1)确定左PFC是否在制定情景检索计划中起关键作用。最近的研究对比了上下文记忆和项目记忆，一致地确定了左PFC，并表明活动不依赖于成功，这表明检索上下文信息的意图是至关重要的。在这里，我们打算分离线索/问题和探针依赖的活动，并确定这些区域是否在基于上下文的检索需求中对不可言语的探针做出反应。(2)基于决策理论对记忆决策准则进行操作。通过控制决策标准的数量、位置和质量，我们将隔离对实现对记忆内容的决策规则至关重要的PFC区域。(3)研究情景检索过程中的半球不对称。最近的证据表明，PFC的半球不对称（特别是背侧和极侧），左侧区域与上下文特定的来源归属有关，而右侧PFC的同源区域在判断项目的近近性或频率时显示相对增加，这可能是基于整体熟悉度评估。通过直接对比对象内匹配材料的近时性、频率和上下文检索，我们将测试两个脑半球是否参与了记忆检索的根本不同方面，超越了早期的构念，如“努力”或“困难”。健康衰老期间的神经系统变化和神经系统疾病（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，由于人们对调节记忆表达的控制或决策过程知之甚少，行为障碍通常是由于表示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区域通常如何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性能下降至关重要。

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.