Nelli Stephanie, Malpani Aayushi, Boonjindasup Max, Serences John T
Neurosciences Graduate Program, University of California, San Diego, CA 92093, USA.
Department of Experimental Psychology, University of Oxford, Oxford OX2 6GG, UK.
Cereb Cortex Commun. 2021 Apr 26;2(2):tgab032. doi: 10.1093/texcom/tgab032. eCollection 2021.
Endogenous alpha oscillations propagate from higher-order to early visual cortical regions, consistent with the observed modulation of these oscillations by top-down factors. However, bottom-up manipulations also influence alpha oscillations, and little is known about how these top-down and bottom-up processes interact to impact behavior. To address this, participants performed a detection task while viewing a stimulus flickering at multiple alpha band frequencies. Bottom-up drive at a participant's endogenous alpha frequency either impaired or enhanced perception, depending on the frequency, but not amplitude, of their endogenous alpha oscillation. Fast alpha drive impaired perceptual performance in participants with faster endogenous alpha oscillations, while participants with slower oscillations displayed enhanced performance. This interaction was reflected in slower endogenous oscillatory dynamics in participants with fast alpha oscillations and more rapid dynamics in participants with slow endogenous oscillations when receiving high-frequency bottom-up drive. This central tendency may suggest that driving visual circuits at alpha band frequencies that are away from the peak alpha frequency improves perception through dynamical interactions with the endogenous oscillation. As such, studies that causally manipulate neural oscillations via exogenous stimulation should carefully consider interacting effects of bottom-up drive and endogenous oscillations on behavior.
内源性阿尔法振荡从高阶视觉皮层区域传播到早期视觉皮层区域，这与自上而下因素对这些振荡的调节作用一致。然而，自下而上的操作也会影响阿尔法振荡，而对于这些自上而下和自下而上的过程如何相互作用以影响行为，我们知之甚少。为了解决这个问题，参与者在观看以多个阿尔法频段频率闪烁的刺激时执行检测任务。自下而上以参与者的内源性阿尔法频率驱动，根据其内源性阿尔法振荡的频率而非幅度，会损害或增强感知。快速阿尔法驱动会损害内源性阿尔法振荡较快的参与者的感知性能，而振荡较慢的参与者则表现出增强的性能。当接受高频自下而上驱动时，这种相互作用反映在阿尔法振荡较快的参与者的内源性振荡动力学较慢，而内源性振荡较慢的参与者的动力学较快。这种中心趋势可能表明，以远离阿尔法频率峰值的阿尔法频段频率驱动视觉回路，通过与内源性振荡的动态相互作用来改善感知。因此，通过外源性刺激因果性地操纵神经振荡的研究应仔细考虑自下而上驱动和内源性振荡对行为的相互作用效应。
