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征的机制 通过大脑皮层网络。神经元增益，测量为刺激输入和刺激之间的关系的连续斜率 细胞输出量是神经元对刺激敏感性的量度，也是单个细胞的贡献的决定性因素 神经元连接到网络操作。以前的工作已经确定了网络驱动的突触活动在调制中的作用 大脑皮层神经元的输入输出增益。此外，本地网络输出之间的同步Q‘可以确定 网络活动对神经元增益的影响程度。此前的研究也表明，收益 调节和群体同步性在视觉知觉中起中介作用。然而，即使在最早的阶段， 皮质视觉处理，单个神经元和周围局部网络之间的关系很差 明白了。因此，这里提出的工作的主要目标是1)确定细胞之间的关系 对比度增益控制和网络同步的机制以及2)检查种群之间的相互作用(H 同步性和视觉感知。最后，第一个目标集中在许多同时记录的大脑皮层 神经元在刺激呈现过程中具有不同的特性。第二个目标将使用行为任务，其中 清醒的跳水动物在一系列实验中辨别不同对比的视觉刺激，这是一项任务 将与组成初级视觉皮质局部网络的神经细胞的群体记录结合在一起。这个 这些实验的结果有望为时间动力学之间的关系提供新的见解。 种群活动和增益控制的细胞机制。此外，他们还将更好地了解 同步大脑皮层网络活动在视觉感知中的作用。

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.