Form and Motion Integration

对运动的敏感性具有重要的适应性意义。虽然单一单位的研究提供了详细的 关于个别皮质区域运动反应动力学的信息和人类功能核磁共振研究 绘制了多个区域的缓慢血流动力学反应图，这两种方法都没有提供对 整个动作处理网络的功能动力学。我们已经开发了基于脑电的源成像 和信号分析工具，我们将使用这些工具来开发运动处理的预测动力学模型 整个大脑皮层的空间分辨率约为2厘米或更小。 我们建议使用刺激来绘制负责远程表观运动的人类大脑皮层区域。 以及类似于用于研究单个单元中的方向选择性的分析程序。在目标1中 我们将使用脑电源成像和知觉测量来比较时空的功能形式 长程与短程表观运动背后的相互作用，并绘制出它们的生成地点。 第二个实验将改变观察者S的任务，以确定自上而下(反馈)的程度 对表观运动加工的影响。在第三个实验中，双稳态的表观运动刺激将是 用来比较在感知到明显运动时和感觉不到运动时的反应。 超越了发展从初级感官区域到联想的一般原则 对于纹外皮质在任何物种中的发育情况，我们都知之甚少。因为远距离飞行 表观运动激活在功能上远离运动处理区域的皮质区域 枕极，是探索这些地区发展的理想探头。第二个目标将应用最近的技术 脑电源成像技术在纹外皮质运动反应研究中的进展 发育中的人类婴儿，年龄在2到6个月之间。我们将检验这一假设，即长程 与空间交互相比，运动系统中的时空交互相对早熟 表格系统。 当斜视或弱视出现在发育早期时，正常的 当立体视觉丧失时，视差和单眼深度线索的深度就会中断。我们建议测试一下 发展假说：立体视觉对运动的正常发展起指导作用 对光流敏感的处理机制。这一假设是由一项发现推动的，即患者 斜视患者的正常视力对整体运动具有更高的阈值。一系列 实验将确定1)时序异常是否与知觉运动处理有关 缺陷2)计时缺陷是否与立体视觉缺陷有关以及3)计时缺陷是否 异常是正在经历明显运动的刺激所特有的，或者它们是否代表着 时间整合的普遍中断。

Sensitivity to motion is of vital adaptive significance. While single unit studies have provided detailed information on the dynamics of motion responses in individual cortical areas and human fMRI studies have mapped slow hemodynamic responses in multiple areas, neither approach provides an analysis of the functional dynamics of the entire motion processing network. We have developed EEG-based source-imaging and signal analysis tools that we will use to develop a predictive dynamical model of motion processing throughout cortex at a spatial resolution that is on the order of 2 cm or less. We propose to map the human cortical areas responsible for long-range apparent motion, using stimuli and analysis procedures that are analogous to those used to study direction selectivity in single-units. In Aim 1 we will use EEG-source imaging and perceptual measurements to compare the functional form of spatiotemporal interactions underlying long- versus short-range apparent motion and to map their sites of generation. The second experiment will vary the observer¿s task in order to determine the extent of top-down (feedback) influences on apparent motion processing. In a third experiment, a bistable apparent motion stimulus will be used to compare responses during episodes when apparent motion is perceived to when it is not. Beyond the general principle that development proceeds from primary sensory areas to association areas, very little is known about the development of extra-striate cortex in any species. Because long-range apparent motion activates cortical areas that are functionally distant from motion processing areas at the occipital pole, it is an ideal probe of development in these areas. The second Aim will apply recent technical developments in EEG source-imaging to the study of motion responses in the extra-striate cortex of typically developing humans infants between two and six months of age. We will test the hypothesis that long-range spatio-temporal interactions in the motion system is relatively precocious compared to spatial interactions in the form system. When strabismus or amblyopia are present during early development, the normal covariation between depth from disparity and monocular depth cues is broken when stereopsis is lost. We propose to test the developmental hypothesis that stereopsis serves an instructive role for the normal development of motion processing mechanisms sensitive to optic flow. This hypothesis is motivated by the finding that patients with strabismus have elevated thresholds for global motion in their normal acuity fellow eyes. A series of experiments will determine 1) whether timing abnormalities are associated with perceptual motion processing deficits 2) whether timing deficits are associated with deficient stereopsis and 3) whether the timing abnormalities are specific to stimuli that are undergoing apparent motion or whether they represent a more general disruption of temporal integration.