Department of Psychology, University of Konstanz, 78457 Konstanz, Germany.
Cereb Cortex. 2012 Jul;22(7):1604-13. doi: 10.1093/cercor/bhr232. Epub 2011 Sep 5.
The anticipation of stimuli facilitates the top-down preparation of neuronal tissue involved in the processing of forthcoming targets. Increasing evidence in the visual modality emphasizes the anticipatory adjustment of visual cortex excitability through modulations of oscillatory alpha power. In the auditory system, however, this relationship has not yet been established. Furthermore, the association between anticipatory modulations of auditory alpha power and a potential top-down network within these anticipatory preparation processes remains unexplained. To disclose these processes, we recorded magnetoencephalography while visually cuing participants to attend to either ear and to anticipate forthcoming auditory stimuli. For the cue-stimulus phase, we expected an asymmetric modulation of auditory alpha power when attending to the left or right ear, assuming that frontoparietal regions would phase synchronize with the auditory cortex in an asymmetric pattern. Beamformer source solutions demonstrate an asymmetric modulation of auditory alpha power following visual cues expressed in a strong right auditory alpha power increase when attending to the right ear. Furthermore, the right auditory cortex is functionally connected to the frontal eye fields during the ipsilateral alpha increase. Altogether, these results contribute significantly to the understanding of how auditory anticipation acts on a local as well as on a network level.
对刺激的预期促进了涉及即将到来目标处理的神经元组织的自上而下的准备。越来越多的视觉模态证据强调了通过调制振荡 alpha 功率来对视觉皮层兴奋性进行预期性调节。然而，在听觉系统中，这种关系尚未建立。此外，听觉 alpha 功率的预期调制与这些预期准备过程中的潜在自上而下网络之间的关联仍然没有得到解释。为了揭示这些过程，我们在视觉提示参与者注意左耳或右耳并预期即将到来的听觉刺激时记录了脑磁图。对于提示-刺激阶段，我们假设额顶区域将以不对称的模式与听觉皮层相位同步，当注意左耳或右耳时，我们预计听觉 alpha 功率会出现不对称调制。波束形成器源解表明，在右耳注意时，听觉 alpha 功率的不对称调制表现为右侧听觉 alpha 功率的强烈增加。此外，在同侧 alpha 增加期间，右听觉皮层与额眼区之间存在功能连接。总的来说，这些结果对理解听觉预期如何在局部和网络层面上起作用有重要贡献。
