Prefrontal contributions to phase-dependent representation of visual information

节律性振荡在大脑活动中的作用长期以来都是这两个主题的主题 投机和研究。最近的证据支持这些理论而不是同步 大脑区域之间的振荡有助于调节它们之间的连接强度； 据报道，在认知功能过程中，区域之间的耦合发生了这样的变化，包括 注意力和工作记忆。信息也可以编码在神经元动作的时序中 与这些振荡相关的电势；事实上，这种“相位编码”有时可以代表 与仅在射击率上可用的信息不同。这些实验将决定 在工作记忆和眼睛过程中，是否使用相位编码来表示视觉信息 运动，并测试前额叶和视皮层之间的相互作用在调节中的作用 这种相位编码。前额叶信号在视皮层相位编码调制中的作用 使用前额叶和视觉区域之间的两个相关同步测量进行测试 在记忆维持期间，以及对前额叶活动的药物操纵。 药物激活将被用来测试视觉皮质中的某些活动模式 足以将感觉信号输入工作记忆。最后，一个阶段的能力 关于眼球运动时间的多路信息的代码，从而消除了来源的歧义 感官信号的传递和扩展将直接影响视觉系统的信息容量 检查过了。了解相位编码对视觉表示的贡献，以及 前额叶和视觉皮质之间的相互作用在调节这种表征中的作用， 将为涉及前额叶受损的神经疾病提供一个必要的比较点- 感官相互作用，如精神分裂症、阿尔茨海默病、注意缺陷多动 精神障碍和自闭症谱系障碍。

The function of rhythmic oscillations in brain activity has long been a subject of both speculation and research. Recent evidence supports theories than synchronization of such oscillations between brain areas can contribute to modulating the strength of their connectivity; such changes in coupling between areas have been reported during cognitive functions including attention and working memory. Information can also be encoded in the timing of neuron’s action potentials relative to these oscillations; indeed, such ‘phase coding’ can sometimes represent different information than is available in the firing rate alone. These experiments will determine whether phase coding is used to represent visual information during working memory and eye movements, and test the role of interactions between prefrontal and visual cortex in modulating this phase coding. The role of prefrontal signals in modulating phase coding in visual cortex will be tested using both correlative measures of synchronization between prefrontal and visual areas during memory maintenance, and pharmacological manipulation of prefrontal activity. Pharmacological activation will be used to test whether certain patterns of activity in visual cortex are sufficient to gate entry of a sensory signal into working memory. Lastly, the ability of a phase code to multiplex information around the time of eye movements, thus disambiguating the source of sensory signals and expanding the information capacity of the visual system will be directly examined. Understanding the contribution of phase coding to the visual representation, along with the role of interactions between prefrontal and visual cortex in modulating such representations, will provide a necessary comparison point for neurological disorders involving impaired prefrontal- sensory interactions, such as schizophrenia, Alzheimer’s disease, attention deficit hyperactivity disorder, and autism spectrum disorders.