Systematic Artifact Reduction in Auditory fMRI

听觉 fMRI 中的系统伪影减少

• 批准号: 7034120
• 负责人: THOMAS M TALAVAGE
• 金额: $ 35.51万
• 依托单位: PURDUE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-02-01 至 2010-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7034120
• 关键词: clinical research; measurement; noise; reduction

DESCRIPTION (provided by applicant): Functional magnetic resonance imaging (fMRI) using echo-planar imaging (EPI) results in generation of a systematic confound-acoustic noise ("acoustic imaging noise")-that can interfere with the fMRI measurement of cortical activity related to a desired (acoustic) stimulus. Acoustic imaging noise is unavoidably perceived by a hearing subject, leading to neuronal activity throughout the auditory pathway, including cortex. Perception of acoustic imaging noise can alter sensory perception of the desired stimulus-an alteration that will affect physiologic activity and distort measurement of the hemodynamic response (HDR) to the desired stimulus. Methods, initially directed at auditory fMRI, are proposed to develop correction algorithms that may be used to correct distortions of the "ideal" HDR (that measured in the absence of confound) associated with systematic confounds. Significant benefit to the fMRI community arises from the process by which the correction algorithm is developed, as the process may be applied to other systematic confounds known to be associated with acquisition of fMRI data. The specific aims of this research are summarized as follows: Aim 1: Obtain "ideal" measurements of the HDR to the systematic confound of acoustic imaging noise for blipped-EPI at 1.5T. Aim 2: Obtain non-ideal measurements of HDRs to a desired (acoustic) stimulus, parameterized by variations in the systematic confound (acoustic imaging noise), allowing quantification of interactions between the HDRs. Aim 3: Develop correction algorithms to compensate for distortions present in non-ideal HDR measurements to a desired (acoustic) stimulus, such that resulting HDR estimates resemble those which would be obtained in absence of the systematic confound (acoustic imaging noise). Relevance: Improvements in localization accuracy and detection sensitivity for fMRI experiments conducted in the presence of repeated confounds (e.g., acoustic noise associated with imaging) will allow more precise discrimination of cortical responses to stimuli that may differ only in a subtle fashion. These benefits will provide greater confidence in location and extent of detected activity, significantly impacting human brain mapping, but also directly benefiting efforts at pre-surgical mapping.

描述(由申请人提供)：使用回声平面成像(EPI)的功能磁共振成像(FMRI)导致产生系统混淆的声学噪声(声学成像噪声)，其可能干扰与所需(声学)刺激相关的皮质活动的fMRI测量。听觉受试者不可避免地会感觉到声成像噪声，导致神经元活动贯穿整个听觉通路，包括大脑皮层。对声成像噪声的感知可以改变对所需刺激的感觉感知--这种改变将影响生理活动并扭曲对所需刺激的血流动力学响应(HDR)的测量。提出了最初针对听觉功能磁共振成像的方法，以开发校正算法，该算法可用于校正与系统混淆相关的“理想”HDR(在没有混淆的情况下测量的)的失真。由于该过程可应用于已知与采集fMRI数据相关的其他系统混淆，因此从开发校正算法的过程中可对fMRI社区产生显著的益处。本研究的具体目标概括如下：目标1：获得对1.5T的BLIPED-EPI声成像噪声的系统混淆的HDR的“理想”测量。目标2：通过系统混淆(声成像噪声)的变化，获得对期望的(声)刺激的HDR的非理想测量，允许量化HDR之间的相互作用。目标3：开发校正算法，以补偿非理想HDR测量中存在的对所需(声)刺激的失真，从而使所得到的HDR估计类似于在没有系统混淆(声成像噪声)的情况下获得的估计。相关性：在存在重复混杂(例如，与成像相关的声学噪声)的情况下进行的fMRI实验的定位准确性和检测灵敏度的改进，将允许更精确地区分皮质对可能仅有细微差别的刺激的反应。这些好处将对检测到的活动的位置和程度提供更大的信心，显著影响人脑图谱，但也直接受益于手术前图谱的努力。