Radboud University Nijmegen, Donders Institute for Brain, Cognition and Behaviour, The Netherlands.
Radboud University Nijmegen, Donders Institute for Brain, Cognition and Behaviour, The Netherlands.
Neuroimage. 2014 Aug 15;97:134-41. doi: 10.1016/j.neuroimage.2014.04.047. Epub 2014 Apr 23.
What are the spectral signatures of somatosensory attention? Here we show that the answer to this question depends critically on the sensory context in which attention is deployed. We recorded magnetoencephalography (MEG) in humans and investigated tactile spatial attention in two different sensory contexts: in anticipation and during the processing of sustained tactile stimuli. We observe a double dissociation between these contexts and two key electrophysiological correlates of attention: in anticipation we primarily observe an attentional suppression of contralateral alpha and beta oscillations (8-12 and 15-30 Hz, respectively), whereas during stimulus processing we primarily observe an attentional amplification of contralateral gamma oscillations (55-75 Hz). This dissociation is well explained by the different neural states that occur prior and during the stimulus, and on which attention can exert its influence. In line with analogous observations in the visual modality, this suggests that the neural implementation of attention must be understood in relation to context and existing brain states. Consequently, different signatures of attention may contribute to perception in different contexts and, as our data reveals for the attentional modulation of alpha oscillations, these are not always required for attention to improve perception. At the same time, these data demonstrate that the attentional modulations of alpha and gamma oscillations (during, respectively, attentional orienting and attentional selection), are generalizable phenomena across the different sensory modalities.
感觉注意的光谱特征是什么？在这里，我们表明，这个问题的答案取决于注意力部署的感官环境。我们在人类中记录了脑磁图（MEG），并在两种不同的感官环境中研究了触觉空间注意：在预期中和在持续触觉刺激的处理过程中。我们观察到这两种情况之间存在双重分离，以及注意的两个关键电生理相关性：在预期中，我们主要观察到对侧 alpha 和 beta 振荡（分别为 8-12 和 15-30 Hz）的注意力抑制，而在刺激处理过程中，我们主要观察到对侧 gamma 振荡（55-75 Hz）的注意力放大。这种分离很好地解释了在刺激之前和期间发生的不同神经状态，以及注意可以对其施加影响。与视觉模式中的类似观察结果一致，这表明必须根据上下文和现有大脑状态来理解注意力的神经实现。因此，不同的注意特征可能会在不同的环境中对感知产生影响，而且正如我们的数据所揭示的，alpha 振荡的注意调制并不总是需要提高感知。同时，这些数据表明，alpha 和 gamma 振荡的注意力调制（分别在注意力定向和注意力选择期间）是跨不同感觉模式的普遍现象。
