Spectro-Temporal Plasticity in Primary Auditory Cortex

项目摘要 听觉体验可以重塑大脑皮层地图，改变大脑皮层神经元的感受野特性。 成年动物的听觉皮层。这种可塑性的确切形式取决于行为背景， 显着的声学刺激的spectrotemporal特征。这已经通过结合生理和 行为方法在我们以前的实验中，其中spectrotemporal感受野（STRFs）， 与动物行为同步快速、全面表征。实验还 在不同的听觉任务中，使用不同的声学信号， 控制光谱和时间特征。这些结果是一致的适应性可塑性的发现， 运动和其他感觉系统，并支持听觉皮层细胞可能经历快速， 当动物进行不同的听觉活动时，其感受野特性的上下文依赖性变化 行为任务这种可塑性可能涉及对潜在的神经系统的选择性功能重塑。 皮层回路塑造了完成当前听觉任务的最有效的感受野。期间 在过去的5年里，我们探索了这种可塑性如何在雪貂的dPEG和VPr领域表现出来 听觉皮层在这个资助期内，我们希望完成这种可塑性的表征， 研究它在两个重要的认知功能中的作用：序列的分类和编码。我们将 用密集的平面和层状多电极阵列进行我们的生理实验， 作为功能性超声成像，以获得期间和之后神经元活动的全局分布视图 这些实验将有助于理解扩展神经元内的相互作用。 神经网络覆盖了雪貂的大部分听觉后皮层区域，引起适应性可塑性。

Project Summary Auditory experience can reshape cortical maps and transform receptive field properties of neurons in the auditory cortex of the adult animal. The exact form of this plasticity depends on the behavioral context, and the spectrotemporal features of the salient acoustic stimuli. This has been shown by combined physiological and behavioral approaches in our previous experiments in which spectrotemporal receptive fields (STRFs) were rapidly and comprehensively characterized simultaneous with the animal behavior. The experiments also contrasted plasticity in single cells across different auditory tasks employing various acoustic signals with controlled spectral and temporal features. These results are consistent with findings of adaptive plasticity in the motor and other sensory systems and support the hypothesis that auditory cortical cells may undergo rapid, context-dependent changes of their receptive field properties when an animal is engaged in different auditory behavioral tasks. This kind of plasticity would likely involve a selective functional reshaping of the underlying cortical circuitry to sculpt the most effective receptive field for accomplishing the current auditory task. During the last 5 years, we explored how this plasticity manifested itself in the dPEG and VPr fields of the ferret auditory cortex. In this grant period, we hope to complete the characterization of this plasticity and also examine its role in two important cognitive functions: Categorization and Encoding of Sequences. We shall conduct our physiological experiments with dense arrays of planar and laminar multielectrode arrays, as well as functional Ultrasound imaging to gain a view of the global distribution of neuronal activity during and after training These experiments will lead to progress in understanding the interactions within an extended neuronal network covering most of the auditory posterior cortical fields in the ferret which give rise to adaptive plasticity.