Institute for Systems Research, University of Maryland, College Park, Maryland, USA.
Nat Neurosci. 2010 Aug;13(8):1011-9. doi: 10.1038/nn.2598. Epub 2010 Jul 11.
Top-down signals from frontal cortex are thought to be important in cognitive control of sensory processing. To explore this interaction, we compared activity in ferret frontal cortex and primary auditory cortex (A1) during auditory and visual tasks requiring discrimination between classes of reference and target stimuli. Frontal cortex responses were behaviorally gated, selectively encoded the timing and invariant behavioral meaning of target stimuli, could be rapid in onset, and sometimes persisted for hours following behavior. These results are consistent with earlier findings in A1 that attention triggered rapid, selective, persistent, task-related changes in spectrotemporal receptive fields. Simultaneously recorded local field potentials revealed behaviorally gated changes in inter-areal coherence that were selectively modulated between frontal cortex and focal regions of A1 that were responsive to target sounds. These results suggest that A1 and frontal cortex dynamically establish a functional connection during auditory behavior that shapes the flow of sensory information and maintains a persistent trace of recent task-relevant stimulus features.
从前额叶皮层自上而下的信号被认为在感觉处理的认知控制中很重要。为了探索这种相互作用，我们比较了在需要区分参考和目标刺激类别的听觉和视觉任务中，雪貂的前额皮层和初级听觉皮层 (A1) 的活动。前额皮层的反应受到行为门控，选择性地编码目标刺激的时间和不变的行为意义，能够快速起始，并且有时在行为后持续数小时。这些结果与 A1 中先前的发现一致，即注意力引发了频谱时间感受野的快速、选择性、持久性、与任务相关的变化。同时记录的局部场电位显示出在区域间相干性方面的行为门控变化，这些变化在对目标声音有反应的 A1 的局部区域和前额皮层之间被选择性地调制。这些结果表明，在听觉行为期间，A1 和前额皮层动态建立了一种功能连接，这种连接塑造了感觉信息的流动，并保持了最近与任务相关的刺激特征的持久痕迹。
