Gordon Noam, Koenig-Robert Roger, Tsuchiya Naotsugu, van Boxtel Jeroen Ja, Hohwy Jakob
Cognition and Philosophy Lab, Philosophy Department, Monash University, Clayton, Australia.
School of Psychology, The University of New South Wales, Sydney, Australia.
Elife. 2017 Feb 28;6:e22749. doi: 10.7554/eLife.22749.
There is a growing understanding that both top-down and bottom-up signals underlie perception. But it is not known how these signals integrate with each other and how this depends on the perceived stimuli's predictability. 'Predictive coding' theories describe this integration in terms of how well top-down predictions fit with bottom-up sensory input. Identifying neural markers for such signal integration is therefore essential for the study of perception and predictive coding theories. To achieve this, we combined EEG methods that preferentially tag different levels in the visual hierarchy. Importantly, we examined intermodulation components as a measure of integration between these signals. Our results link the different signals to core aspects of predictive coding, and suggest that top-down predictions indeed integrate with bottom-up signals in a manner that is modulated by the predictability of the sensory input, providing evidence for predictive coding and opening new avenues to studying such interactions in perception.
人们越来越认识到，自上而下和自下而上的信号都是感知的基础。但尚不清楚这些信号如何相互整合，以及这如何取决于所感知刺激的可预测性。“预测编码”理论根据自上而下的预测与自下而上的感官输入的匹配程度来描述这种整合。因此，识别这种信号整合的神经标记对于感知和预测编码理论的研究至关重要。为了实现这一点，我们结合了脑电图方法，这些方法优先标记视觉层次结构中的不同水平。重要的是，我们将互调成分作为这些信号之间整合的一种度量进行了研究。我们的结果将不同的信号与预测编码的核心方面联系起来，并表明自上而下的预测确实以一种由感官输入的可预测性调节的方式与自下而上的信号整合，为预测编码提供了证据，并为研究感知中的这种相互作用开辟了新途径。
