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.

该子项目是利用资源的众多研究子项目之一 由 NIH/NCRR 资助的中心拨款提供。子项目的主要支持 并且子项目的首席研究员可能是由其他来源提供的， 包括其他 NIH 来源。 子项目可能列出的总成本 代表子项目使用的中心基础设施的估计数量， NCRR 赠款不直接向子项目或子项目工作人员提供资金。 微扫视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神经元的活动。 微眼跳是否会提高猴子观察者的对比检测阈值尚不清楚，并且与神经生理学实验的解释有关。 为了回答这个问题，我们训练了两只猴子来执行 2AFC 对比度检测任务。 在刺激呈现期间发生微扫视的试验中，表现更差。 影响的幅度不大（阈值变化为 0.2 个对数单位）并且具有颜色特异性：消色差敏感度受损，但红绿敏感度并未受损。 为了探索这种效应的神经基础，我们记录了单个 V1 神经元对白噪声刺激的反应。 微扫视产生尖峰活动的抑制，随后产生兴奋性反弹，这与 L-M 视锥细胞对抗性和 L+M 非对抗性 V1 神经元类似。 我们得出的结论是，猴子的微眼跳增加了亮度对比度检测阈值并调节 V1 神经元的尖峰活动，但行为抑制的亮度特异性很可能是在 V1 的下游实现的。