Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA.
Nat Neurosci. 2011 Feb;14(2):246-51. doi: 10.1038/nn.2688. Epub 2010 Dec 19.
When events occur at predictable instants, anticipation improves performance. Knowledge of event timing modulates motor circuits and thereby improves response speed. By contrast, the neuronal mechanisms that underlie changes in sensory perception resulting from expectation are not well understood. We developed a behavioral procedure for rats in which we manipulated expectations about sound timing. Valid expectations improved both the speed and the accuracy of the subjects' performance, indicating not only improved motor preparedness but also enhanced perception. Single-neuron recordings in primary auditory cortex showed enhanced representation of sounds during periods of heightened expectation. Furthermore, we found that activity in auditory cortex was causally linked to the performance of the task and that changes in the neuronal representation of sounds predicted performance on a trial-by-trial basis. Our results indicate that changes in neuronal representation as early as primary sensory cortex mediate the perceptual advantage conferred by temporal expectation.
当事件在可预测的时刻发生时，预期会提高表现。对事件时间的了解会调节运动回路，从而提高反应速度。相比之下，预期导致的感觉感知变化的神经机制还不是很清楚。我们为大鼠开发了一种行为程序，在该程序中，我们可以操纵对声音时间的预期。有效的预期不仅提高了受试者的运动准备程度，而且提高了他们的表现速度和准确性，这表明了运动准备程度的提高和感知能力的增强。初级听觉皮层中的单细胞记录显示，在预期增强期间，声音的表示得到了增强。此外，我们发现听觉皮层的活动与任务的表现有因果关系，并且声音的神经元表示的变化可以逐次预测表现。我们的结果表明，即使在初级感觉皮层中，神经元表示的变化也可以介导时间预期赋予的感知优势。
