Stereoscopic motion-in-depth perception: fMRI and neurophysiological studies

立体运动深度感知：功能磁共振成像和神经生理学研究

• 批准号: 7738468
• 负责人: Paul Douglas Gamlin
• 金额: $ 18.94万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-12-01 至 2011-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7738468
• 关键词: 3-Dimensional; Accounting; Address; Animals; Anterior; Architecture; Area; Back; Behavior; Brain; Brain region; Cells; Characteristics; Code; Complex; Cues; Data; Defect; Depth Perception; Diagnosis; Diplopia; Electrodes; Eye; Eye Movements; Functional Magnetic Resonance Imaging; Fundus; Grant; Health; Human; Individual; Knowledge; Laboratories; Location; Macaca; Macaca mulatta; Magnetic Resonance Imaging; Monkeys; Motion; Motion Perception; Movement; Neurons; Perception; Population; Process; Property; Protocols documentation; Relative (related person); Reporting; Research; Research Design; Resolution; Retinal; Signal Transduction; Speed; Staging; Stimulus; Strabismus; Structure; Structure of superior temporal sulcus; System; Techniques; Testing; Time; Translating; Visual Fields; base; blood oxygen level dependent; design; insight; interest; intraparietal sulcus; neurophysiology; nonhuman primate; novel; public health relevance; receptive field; relating to nervous system; research study; response; sample fixation; stereoscopic; visual stimulus

Description (provided by applicant): This R21 exploratory proposal is designed to advance the integration of high field fMRI in alert macaque monkeys with "informed" neurophysiology, and to apply it in addressing a long-standing research question regarding the neural processing of stereoscopic 3-D motion. Stereo and motion are usually studied separately, and the cortical regions involved in the binocular perception of motion-in-depth in macaque monkeys are poorly characterized, while those for cyclopean (solely disparity-based) stereomotion perception are unknown. However, in humans, recent studies have identified specialized brain regions specifically involved in cyclopean stereomotion processing, including one near the motion complex hMT+, termed the cyclopean stereomotion region. We have developed techniques for performing fMRI studies at high-field in alert, behaving macaques. Therefore, employing the same visual stimuli as used in humans, we will use fMRI to identify cyclopean stereomotion regions in macaques, and to then characterize neuronal responses within one targeted region. The planned studies are relevant to health, since visual field deficits in stereomotion processing are closely correlated with deficits in vergence eye movements, and the same defect in binocular interaction appears to underlie both abnormal behaviors. Studies of the neural processing of stereomotion in non-human primates will not only provide insights into the cortical areas involved in processing this motion information and in controlling vergence eye movements, but will also potentially aid in the diagnosis and treatment of strabismus and diplopia. Specifically, using fMRI we will examine the cortical areas activated by cyclopean, motion-in-depth stimuli presented with dynamic random-dot stereograms (DRDS). These stimuli will be contrasted with appropriate, fixed-disparity DRDS stimuli. Our preliminary fMRI data from macaques have identified two well-localized foci of activation with these stimuli: one in the superior temporal sulcus (STS) in a location that partially coincides with MSTv, and the other is in the intraparietal sulcus. Next, since this is an exploratory grant of limited duration, we will concentrate our neurophysiological studies on the well-localized focus of activation within the STS. Specifically, using MRI-guided electrode placement in this targeted region, we will search for responsive neurons while the animals view cyclopean, motion-in-depth DRDS stimuli with the only cue to motion-in-depth being the change in disparity over time (CD). Next, using these stimuli, we will determine the receptive field size and location, and the speed tuning and z-axis directional selectivity of the neurons. Then, using RDS stimuli that possess both CD and interocular velocity difference motion-in-depth cues, we will examine neuronal response when both binocular cues to motion-in-depth are present. We will further characterize neuronal responses to stereomotion stimuli with frontoparallel and oblique trajectories, and during vergence eye movements. PUBLIC HEALTH RELEVANCE Accurate binocular alignment of the eyes on targets at different distances requires precisely coordinated movements of the two eyes, known as vergence eye movements; individuals with deficits in vergence eye movements are often strabismic and report diplopia (double-vision). Visual field deficits in stereomotion processing are closely correlated with deficits in vergence eye movements, and it has been suggested that the same defect in binocular interaction underlies both abnormal behaviors (Regan et al., 1986). Our studies of the neural processing of cyclopean stereomotion in non-human primates will not only provide fundamental insights into the cortical mechanisms involved in processing this motion information and in controlling vergence eye movements, but will also potentially aid in the diagnosis and treatment of strabismus and diplopia.

描述（由申请人提供）：该 R21 探索性提案旨在促进警觉猕猴中高场 fMRI 与“知情”神经生理学的整合，并将其应用于解决有关立体 3 神经处理的长期研究问题-D运动。立体和运动通常是分开研究的，猕猴中参与深度运动的双眼感知的皮层区域的特征很少，而独眼（完全基于视差）立体运动感知的皮质区域则未知。然而，在人类中，最近的研究已经确定了专门参与独眼立体运动处理的特殊大脑区域，包括运动复合体 hMT+ 附近的一个区域，称为独眼立体运动区域。我们开发了在高场对警觉、行为举止的猕猴进行功能磁共振成像研究的技术。因此，利用与人类相同的视觉刺激，我们将使用功能磁共振成像来识别猕猴的独眼立体运动区域，然后表征一个目标区域内的神经元反应。计划中的研究与健康相关，因为立体运动处理中的视野缺陷与眼球聚散运动缺陷密切相关，并且双眼相互作用中的相同缺陷似乎是这两种异常行为的基础。对非人类灵长类动物立体运动神经处理的研究不仅可以深入了解参与处理这种运动信息和控制眼球聚散运动的皮层区域，而且还可能有助于斜视和复视的诊断和治疗。具体来说，我们将使用功能磁共振成像检查由动态随机点立体图 (DRDS) 呈现的独眼、深度运动刺激激活的皮质区域。这些刺激将与适当的、固定视差的 DRDS 刺激进行对比。我们对猕猴的初步功能磁共振成像数据已经确定了这些刺激的两个定位良好的激活灶：一个位于颞上沟 (STS)，其位置与 MSTv 部分重合，另一个位于顶内沟。接下来，由于这是一项期限有限的探索性资助，我们将把我们的神经生理学研究集中在 STS 内的局部激活焦点上。具体来说，在这个目标区域使用 MRI 引导的电极放置，我们将在动物观看巨大的、深度运动 DRDS 刺激时寻找响应神经元，而深度运动的唯一线索是视差随时间的变化（光盘）。接下来，使用这些刺激，我们将确定感受野的大小和位置，以及神经元的速度调整和 z 轴方向选择性。然后，使用同时具有 CD 和眼间速度差深度运动线索的 RDS 刺激，我们将检查当双眼深度运动线索都存在时的神经元反应。我们将进一步表征神经元对额平行和倾斜轨迹以及聚散眼球运动期间立体运动刺激的反应。公共健康相关性 眼睛在不同距离的目标上准确地进行双眼对准需要两只眼睛的精确协调运动，称为眼球聚散运动；眼球运动存在缺陷的人通常患有斜视并报告复视（复视）。立体运动处理中的视野缺陷与眼球聚散运动的缺陷密切相关，并且有人认为双眼相互作用中的相同缺陷是这两种异常行为的基础（Regan等人，1986）。我们对非人类灵长类动物的独眼立体运动的神经处理的研究不仅将为处理这种运动信息和控制眼球聚散运动所涉及的皮质机制提供基本的见解，而且还可能有助于斜视和斜视的诊断和治疗。复视。