The neural mechanisms of precision in visual working memory

 描述(由申请人提供)：视觉工作记忆(VWM)对于我们保持关于不再直接看到的刺激的信息的能力是必不可少的。在日常生活中，我们依靠这项技能来维护环境中对象的相关信息，并促进行动计划。重要的是，支持视觉工作记忆的复杂神经机制还没有得到很好的表征，这一领域的仔细研究对于了解健康的人类大脑如何积极地在记忆中保持准确的视觉信息至关重要。有趣的是，视觉信息被编码、维护和从VWM中检索的精确度在健康个体之间差别很大，甚至在单个个体内的不同试验之间也是如此。以往的研究表明，外侧前额叶皮质(PFC)和高阶视觉区如梭形脸部区(FFA)参与了VWM中脸部刺激的编码和维持。然而，目前尚不清楚这些地区如何相互作用，以支持VWM代表的准确维护。因此，这项研究的目标是确定复杂视觉对象如何在视觉工作记忆中保持高精度，并确定导致视觉工作记忆失败和不精确的潜在神经机制。使用不同的行为、功能磁共振成像(FMRI)和并行经颅磁刺激-fMRI方法，拟议的一组实验将研究面部VWM表征的性质，以及这些表征随着时间的推移保持高精度的机制。更具体地说，将检验以下假设：(1)诸如FFA的刺激选择视区通过在视觉刺激不再存在时保持知觉相关的活动来支持精确的VWM，以及(2)外侧PFC向刺激选择区域提供自上而下的输入，或与刺激选择区域进行交互，这有助于维持VWM表征的精确度。这项研究与公共健康相关，因为它将促进我们对颞叶视觉区域和额叶在VWM中各自作用的理解。许多精神和神经疾病，如精神分裂症、痴呆症、中风和创伤性脑损伤，影响额叶和/或颞叶功能；许多其他疾病，如注意力缺陷障碍、物质成瘾和正常衰老，被认为涉及额叶大脑系统的选择性功能障碍。这项拟议的研究将带来关于健康大脑功能的基本知识，这些知识可以为理解、诊断和治疗广泛的临床疾病提供有价值的见解。

 DESCRIPTION (provided by applicant): Visual working memory (VWM) is essential for our ability to maintain information about stimuli that are no longer in direct view. In daily life, we ely on this skill to maintain relevant information about objects in our environment and to facilitate action planning. Importantly, the complex neural mechanisms that support visual working memory are not yet well characterized, and careful research in this area is critical for understanding how the healthy human brain actively maintains precise visual information in memory. Interestingly, the precision with which visual information can be encoded, maintained, and retrieved from VWM varies considerably between healthy individuals, and even from trial to trial within a single individual. Previous research has shown that the lateral prefrontal cortex (PFC) and higher-order visual areas like the fusiform face area (FFA) are involved in the encoding and maintenance of face stimuli in VWM. However, it remains unclear how these areas interact to support the precise maintenance of VWM representations. Therefore, the goal of the proposed research is to determine how complex visual objects are maintained with high precision in VWM, and to identify potential neural mechanisms responsible for VWM failures and imprecision. Using diverse behavioral, functional magnetic resonance imaging (fMRI), and concurrent transcranial magnetic stimulation - fMRI approaches, the proposed set of experiments will investigate the nature of VWM representations for faces, and the mechanisms by which those representations are maintained with high precision over time. More specifically, the following hypotheses will be tested: (1) a stimulus-selective visual area such as the FFA supports precise VWM by maintaining perception-related activity when a visual stimulus is no longer present, and (2), that the lateral PFC provides top-down inputs to, or engages in interactions with, stimulus-selective areas that aid in sustaining the precision of VWM representations. This research is relevant to public health because it will advance our understanding of the respective roles of temporal visual areas and the frontal lobes in VWM. Many psychiatric and neurological disorders such as schizophrenia, dementia, stroke and traumatic brain injury affect frontal and/or temporal lobe function; and many other conditions such as attention-deficit disorder, substance addiction, and normal aging are proposed to involve selective dysfunction of frontal brain systems. The proposed research will lead to basic knowledge about healthy brain function that can provide valuable insights into the understanding, diagnosis and treatment of a wide range of clinical conditions.