Hertie Institute for Clinical Brain Research, University Medical Center Tübingen, 72076 Tübingen, Germany; International Max Planck Research School for the Mechanisms of Mental Function and Dysfunction, University of Tübingen, Tübingen, Germany.
Department of Psychology and the Helen Wills Neuroscience Institute, UC Berkeley, Berkeley, CA 94720, USA.
Curr Biol. 2023 Nov 20;33(22):4893-4904.e3. doi: 10.1016/j.cub.2023.09.065. Epub 2023 Oct 17.
Contemporary models conceptualize spatial attention as a blinking spotlight that sequentially samples visual space. Hence, behavior fluctuates over time, even in states of presumed "sustained" attention. Recent evidence has suggested that rhythmic neural activity in the frontoparietal network constitutes the functional basis of rhythmic attentional sampling. However, causal evidence to support this notion remains absent. Using a lateralized spatial attention task, we addressed this issue in patients with focal lesions in the frontoparietal attention network. Our results revealed that frontoparietal lesions introduce periodic attention deficits, i.e., temporally specific behavioral deficits that are aligned with the underlying neural oscillations. Attention-guided perceptual sensitivity was on par with that of healthy controls during optimal phases but was attenuated during the less excitable sub-cycles. Theta-dependent sampling (3-8 Hz) was causally dependent on the prefrontal cortex, while high-alpha/low-beta sampling (8-14 Hz) emerged from parietal areas. Collectively, our findings reveal that lesion-induced high-amplitude, low-frequency brain activity is not epiphenomenal but has immediate behavioral consequences. More generally, these results provide causal evidence for the hypothesis that the functional architecture of attention is inherently rhythmic.
当代的模型将空间注意力概念化为一个闪烁的聚光灯，它依次对视觉空间进行采样。因此，即使在被认为是“持续”注意的状态下，行为也会随时间波动。最近的证据表明，额顶网络中的节律性神经活动构成了节律性注意采样的功能基础。然而，支持这一观点的因果证据仍然缺乏。使用侧化空间注意任务，我们在额顶注意网络中有局灶性病变的患者中解决了这个问题。我们的结果表明，额顶病变会导致周期性的注意力缺陷，即与潜在的神经振荡相一致的、具有时间特异性的行为缺陷。在最佳相位期间，注意引导的感知敏感性与健康对照组相当，但在兴奋性较低的亚周期期间会减弱。θ依赖性采样（3-8 Hz）取决于前额叶皮层，而高α/低β采样（8-14 Hz）则来自顶叶区域。总的来说，这些发现表明，病变引起的高振幅、低频率脑活动不是偶然现象，而是有直接的行为后果。更一般地说，这些结果为注意力的功能结构本质上是有节奏的假设提供了因果证据。
