NEUROPHYSIOLOGY OF VISION

视觉神经生理学

• 批准号: 8357595
• 负责人: Gregory D Horwitz
• 金额: $ 10.43万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-05-01 至 2012-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8357595
• 关键词: Behavioral; Color; Detection; Funding; Grant; Human; Individual; Monkeys; National Center for Research Resources; Neurons; Noise; Performance; Primates; Principal Investigator; Research; Research Infrastructure; Resources; Retinal Cone; Source; Specificity; Stimulus; Training; United States National Institutes of Health; Ursidae Family; V1 neuron; Visual Cortex; base; cost; luminance; neurophysiology; relating to nervous system; research study; response

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Microsaccades can elevate contrast detection thresholds of human observers and modulate the activity of neurons in monkey visual cortex. Whether microsaccades elevate contrast detection thresholds in monkey observers is not known and bears on the interpretation of neurophysiological experiments. To answer this question, we trained two monkeys to perform a 2AFC contrast detection task. Performance was worse on trials in which a microsaccade occurred during the stimulus presentation. The magnitude of the effect was modest (threshold changes of 0.2 log units) and color specific: achromatic sensitivity was impaired but red-green sensitivity was not. To explore the neural basis of this effect, we recorded the responses of individual V1 neurons to a white noise stimulus. Microsaccades produced a suppression of spiking activity followed by a excitatory rebound that was similar for L-M cone-opponent and L+M non-opponent V1 neurons. We conclude that microsaccades in the monkey increase luminance contrast detection thresholds and modulate the spiking activity of V1 neurons, but the luminance-specificity of the behavioral suppression is likely implemented downstream of V1.

该副本是利用资源的众多研究子项目之一 由NIH/NCRR资助的中心赠款提供。对该子弹的主要支持 而且，副投影的主要研究员可能是其他来源提供的 包括其他NIH来源。 列出的总费用可能 代表subproject使用的中心基础架构的估计量， NCRR赠款不直接向子弹或副本人员提供的直接资金。 微扫描可以提高人类观察者的对比检测阈值，并调节猴子视觉皮层中神经元的活性。 Microsaccades是否提升了猴观察者中的对比度检测阈值，尚不清楚，并且对神经生理实验的解释有任何意义。 为了回答这个问题，我们训练了两只猴子执行2AFC对比检测任务。 在刺激呈现过程中发生微扫描的试验中的性能较差。 效果的幅度是适度的（阈值的阈值变化为0.2 log单元）和颜色特异性：可观的灵敏度受到损害，但红绿色的灵敏度却没有。 为了探索这种作用的神经基础，我们记录了单个V1神经元对白噪声刺激的反应。 微扫描产生了尖峰活性的抑制，然后产生了兴奋性反弹，与L-M锥形 - op子和L+M非频率V1神经元相似。 我们得出的结论是，猴子中的微扫描会增加亮度对比检测阈值并调节V1神经元的尖峰活性，但是行为抑制的亮度特异性可能是在V1下游实现的。