经颅交流电刺激(tACS)已被广泛用于以特定频率的方式改变正在进行的大脑节律,以调节相关的认知功能。包括视觉功能。因此,它是探索神经振荡在认知中的因果作用的有用工具。视觉功能可以通过培训得到实质性改善,这被称为视觉感知学习(VPL)。然而,tACS是否以及如何调节VPL尚不清楚。
这项工作旨在探讨tACS如何调节VPL以及神经振荡在VPL中的作用。
采用了学科间设计。受试者被分配到六组,并每天进行五次培训以执行定向歧视任务。在培训期间,五组分别在6、10、20、40和假10Hz接受枕骨tACS刺激,一组在感觉运动区域受到10HztACS的刺激。
与假刺激相比,10Hz的枕骨tACS,但不是在其他频率,加速了感知学习,提高了性能。然而,当将10HztACS递送至感觉运动区域时,这些调节作用不存在.此外,训练结束后,tACS诱导的表现改善至少持续两个月.
TACS可以以特定于频率和位置的方式促进方位辨别学习。我们的发现为α振荡在增强VPL中的关键作用提供了强有力的证据,并为设计有效的神经调节方案提供了新的思路,该方案可以促进神经眼科疾病患者的康复。
Transcranial alternating current stimulation (tACS) has been widely used to alter ongoing brain rhythms in a frequency-specific manner to modulate relevant cognitive functions, including visual functions. Therefore, it is a useful tool for exploring the causal role of neural oscillations in cognition. Visual functions can be improved substantially by training, which is called visual perceptual learning (VPL). However, whether and how tACS can modulate VPL is still unclear.
This work aims to explore how tACS modulates VPL and the role of neural oscillations in VPL.
A between-subjects design was adopted. Subjects were assigned to six groups and undertook five daily training sessions to execute an orientation discrimination task. During training, five groups received occipital tACS stimulation at 6, 10, 20, 40, and sham 10 Hz respectively, and one group was stimulated at the sensorimotor regions by 10 Hz tACS.
Compared with the sham stimulation, occipital tACS at 10 Hz, but not at other frequencies, accelerated perceptual learning and increased the performance improvement. However, these modulatory effects were absent when 10 Hz tACS was delivered to the sensorimotor areas. Moreover, the tACS-induced performance improvement lasted at least two months after the end of training.
TACS can facilitate orientation discrimination learning in a frequency- and location-specific manner. Our findings provide strong evidence for a pivotal role of alpha oscillations in boosting VPL and shed new light on the design of effective neuromodulation protocols that can facilitate rehabilitation for patients with neuro-ophthalmological disorders.