Impact of local network dynamics on visual cortex function

这个项目的长期目标是帮助我们理解视觉表现的机制 通过皮层网络。神经元增益，测量为刺激输入和 细胞输出是神经元对刺激敏感性的衡量标准，也是单个细胞贡献的定义元素 神经元到网络操作。以前的工作已经确定了网络驱动的突触活动在调节神经元的功能中的作用。 皮层神经元的输入输出增益。此外，本地网络输入之间的同步可以确定本地网络的输入。 网络活动对神经元增益的影响程度。以前的研究也表明， 调制和群体同步性在调节视觉感知中起作用。然而，即使在最早的阶段， 皮层视觉处理，个别神经元和周围的局部网络之间的关系很差 明白因此，本文提出的工作的主要目标是：1）确定细胞间的关系， 对比度增益控制和网络同步的机制; 2）研究群体之间的相互作用（H） 同步和视觉感知。最后，第一个目标集中在许多同时记录的皮层 神经元在呈现具有不同特性的刺激期间。第二个目标将使用行为任务， 在一系列实验中，清醒的动物区分不同对比度的视觉刺激， 将与构成初级视觉皮层中局部神经元的neimms的群体记录相结合。的 期望这些特征的结果提供对时间动态之间的关系的新的见解。 种群活动和增益控制的细胞机制。此外，他们将更好地了解 同步皮层网络活动在视知觉中的作用

The long-term objective ofthis project is to contribute to our understanding ofthe mechanisms of visual representation by cortical networks. Neuronal gain, measured as the continuous slope ofthe relationship between stimulus input and cellular outpiut, is a measure of neuronal sensitivity to the stimulus and a defining element ofthe contribution of single neurons to network operations. Previous work has identified a role for network-driven synaptic activity in modulating the input-output gain of cortical neurons. In addition, synchroiQ' between local network mputs may determine the magnitude ofthe impact of network activity on neuronal gain. Previous studies have also suggested that gain modulation and population synchrony play roles in mediating visual perception. However, even at the earliest stages of cortical visual processing, die relationship between individual neurons and the surrounding local network is poorly understood. The main goals ofthe work proposed here are therefore 1) to determine the relationship betweoi cellular mechanisms of contrast gain control and networic synchrony and 2) to examine tiie interacti(H) between population synchrony and visual perception. To tiiat end, the first Aim focused on many simultaneous recordings of cortical neurons during presentation of stimuli with varying prqierties. The second Aim will use a behavioral task in which awake bdiaving animals discriminate between visual stimuli of vaiying contrast In one series of expraiments, tiiis task will be combined witii population recordings of neimms that make up local netwoiks in primary visual cortex. The results of these eiqieriments are expected to provide novel insights into the relation^p between tiie temporal dynamics of population activity and cellular mechanisms of gain control. In addition, they will graierate a better understanding of tiie role of synchronous cortical networic activity in visual perception.