Adaptation and multivoxel codes in high-level visual cortex

高级视觉皮层的适应和多体素编码

基本信息

批准号：
8510186
负责人：
RUSSELL A EPSTEIN
金额：
$ 20万
依托单位：
UNIVERSITY OF PENNSYLVANIA
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-04-01 至 2015-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8510186
关键词：
Address Amblyopia Anterior Area Brain region Categories Cereals Code Complex Data Set Disease Episodic memory Fruit Functional Magnetic Resonance Imaging Goals Health Imaging Techniques Individual Investigation Knowledge Lateral Linguistics Measures Methods Neurons Oysters Pattern Process Recovery Shapes Signal Transduction Specificity Stimulus Synapses Techniques Testing Time Ursidae Family Vision Visual Visual Cortex Visual system structure Work analytical tool base blind cognitive neuroscience expectation indexing information processing neuromechanism operation public health relevance relating to nervous system research study response

Address Amblyopia Anterior Area Brain region Categories Cereals Code Complex Data Set Disease Episodic memory Fruit Functional Magnetic Resonance Imaging Goals Health Imaging Techniques Individual Investigation Knowledge Lateral Linguistics Measures Methods Neurons Oysters Pattern Process Recovery Shapes Signal Transduction Specificity Stimulus Synapses Techniques Testing Time Ursidae Family Vision Visual Visual Cortex Visual system structure Work analytical tool base blind cognitive neuroscience expectation indexing information processing neuromechanism operation public health relevance relating to nervous system research study response

展开

项目摘要

DESCRIPTION (provided by applicant): A core concern of cognitive neuroscience is understanding the representational distinctions made by different brain regions. Two techniques are commonly used in functional magnetic resonance imaging (fMRI) studies to investigate this issue: multivoxel pattern analysis (MVPA) and fMRI adaptation (fMRIa). Whereas MVPA examines the voxelwise response patterns elicited by different stimuli to determine which items elicit patterns that are distinguishable, fMRIa examines the effect of repeating items over time under the hypothesis that repetition of representationally-similar items will elicit a reduced response. Although MVPA and fMRIa have become part of the central toolkit of cognitive neuroscience, little is known for certain about the neuronal mechanisms that underlie these two techniques. Consequently, it has been difficult to relate results obtained through MVPA to results obtained through fMRIa. Indeed, previous work from our lab has shown that apparently inconsistent results can be obtained from fMRIa and MVPA, even when these techniques are applied to the same dataset. The main goal of the current project is to test several hypotheses about the different neuronal mechanisms that might underlie MVPA and fMRIa. Specifically, we will test whether fMRIa indexes neuronal or subneuronal tuning (Exp. 1), stimulus similarity or perceptual expectations (Exp. 2), and we will test the spatial scale of functional organization indexed by MVPA (Exp. 3). The focus of this preliminary project will be on fMRI signals in the parahippocampal place area (PPA) during viewing of real-world visual scenes and in the lateral occipital complex (LOC) during the viewing of objects. Although the current experiments do not directly examine recovery or disease, they will, if successful, provide important analytical tools for such investigations. For example, attempts to use MVPA and fMRIa to understand plasticity and cortical reorganization in amblyopia, or after recovery of sight in the blind, can only bear fruit if the interpretation of the findings in terms of underlying neural mechanisms is fully understood.

描述（由申请人提供）：认知神经科学的核心关注点是理解不同大脑区域的代表性区别。两种技术通常用于功能磁共振成像（fMRI）研究以研究此问题：多毒素模式分析（MVPA）和fMRI适应性（FMRIA）。尽管MVPA检查了不同刺激引起的自称响应模式，以确定哪些项目引起的模式可区分的模式，但FMRIA检查了随着时间的推移重复项目的效果，即代表性相似的项目的重复会导致响应降低。尽管MVPA和FMRIA已成为认知神经科学中心工具包的一部分，但对这两种技术的基础的神经元机制知之甚少。因此，很难将通过MVPA获得的结果与通过FMRIA获得的结果联系起来。确实，我们实验室的先前工作表明，即使将这些技术应用于同一数据集，也可以从FMRIA和MVPA获得不一致的结果。当前项目的主要目的是检验有关可能是MVPA和FMRIA的不同神经元机制的几个假设。具体而言，我们将测试FMRIA索引索引神经元或下神经元调整（exp。1），刺激相似性或感知期望（exp。2），我们将测试由MVPA索引的功能组织的空间量表（Exp。3）。该初步项目的重点将放在在观看现实世界视觉场景和观察物体观看过程中侧面枕形综合体（LOC）中的parahampocampal位置（PPA）的fMRI信号上。尽管当前的实验未直接检查恢复或疾病，但如果成功，它们将为此类研究提供重要的分析工具。例如，尝试使用MVPA和FMRIA来理解弱视中的可塑性和皮质重组，或者在盲人中恢复视力后，只有在对基本神经机制的发现的解释时，才能承受成果。