Form and Motion Integration

描述（由申请人提供）：复杂环境中的视觉需要能够在大部分视野中整合方向和运动的局部测量。此外，这种整合必须对行为相关的刺激具有选择性，并且视觉系统必须能够将相关刺激信息与背景杂波分开。如何实现这一点将在正常的视觉发育和弱视患者使用心理物理，电生理和功能成像方法的组合进行研究。我们将使用源定位技术将由fMRI确定的皮质源与高密度EEG/MEG记录的神经元活动联系起来。注意力影响反应灵敏度的程度将通过比较观察者对测试刺激进行运动/形式相关辨别时的EEG反应与观察者执行需要注意力的分心物任务时的反应来确定。将使用心理物理学和电生理学测量来确定具有斜视和/或弱视病史的视觉成熟观察者对全局运动和形状刺激的敏感度。还将在正常发育的婴儿和儿童中确定相同刺激的发育顺序。这些任务可能会探测纹状体外区域的活动，这些区域可能由于延长的发育序列而特别脆弱。

DESCRIPTION (provided by applicant): Vision in complex environments requires the ability to integrate local measurements of orientation and motion over large parts of the visual field. Moreover, this integration must be selective for stimuli that are behaviorally relevant and the visual system must be able to separate relevant stimulus information from background clutter. How this is accomplished will be studied during normal visual development and in patients with amblyopia using a combination of psychophysical, electrophysiological and functional imaging approaches. We will link the cortical sources determined by fMRI to neuronal activity recorded with high-density EEG/MEG using source localization techniques. The degree to which attention influences response sensitivity will be determined by comparing EEG responses when observers are making motion/form relevant discriminations on the test stimuli versus responses made when the observers are performing an attentionally demanding distractor task. Sensitivity to global motion and form stimuli will be determined in visually mature observers with a history of strabismus and/or amblyopia using both psychophysical and electrophysiological measures. Developmental sequences for the same stimuli will also be determined in normally developing infants and children. These tasks are likely to probe activity in extra-striate areas which may be particularly vulnerable due to extended developmental sequences.