Li Rong, Meng Jiayuan, You Jia, Zhou Xiaoyu, Xu Minpeng, Ming Dong
College of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin, 300072 China.
Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, 300072 China.
Cogn Neurodyn. 2024 Apr;18(2):417-429. doi: 10.1007/s11571-023-10008-6. Epub 2023 Oct 4.
Vigilance decrement is a ubiquitous problem in attention-demanding tasks. Therefore, it is significant to develop neuromodulation methods to mitigate the negative neural effect of vigilance decrement. As one of the non-invasive brain stimulation techniques, visual flicker/rhythmic visual stimulation (RVS) has been proposed to entrain neural oscillations and thereby modulate cognitive processes supported by these brain rhythms, but its effects on vigilance decrement are still unclear. Here, we investigated the effect of gamma flicker on vigilance decrement and its underlying neural mechanism. Thirty participants were recruited to perform a 12-min vigilance task. They were required to discriminate the orientation of lateralized triangle targets with/without 40-Hz RVS background. As a result, it was found that 40-Hz RVS mitigated the decrease in perceptual sensitivity ( ) with time-on-task, a typical adverse effect on behaviors caused by vigilance decrement. Electroencephalography (EEG) results showed that 40-Hz RVS could reduce the significant decline of post-stimulus theta-band inter-trial coherence (ITC) in the prefrontal cortex (PFC) with time-on-task. Regression analysis further revealed that the anterior theta-band ITC was significantly correlated to perceptual sensitivity ( ) in a positive manner. These findings indicated that gamma flicker to the visual cortex had a cross-frequency neuromodulation effect on low-frequency EEG responses over the long-range PFC region. Furthermore, this study provides new insights into the neural effects of 40-Hz RVS, which could impact time-on-task effects on vigilance behaviors and alter the utilization of attentional resources.
The online version contains supplementary material available at 10.1007/s11571-023-10008-6.
警觉性下降是需要注意力的任务中普遍存在的问题。因此，开发神经调节方法以减轻警觉性下降的负面神经效应具有重要意义。作为非侵入性脑刺激技术之一，视觉闪烁/节律性视觉刺激（RVS）已被提出用于诱导神经振荡，从而调节由这些脑节律支持的认知过程，但其对警觉性下降的影响仍不清楚。在这里，我们研究了伽马闪烁对警觉性下降的影响及其潜在的神经机制。招募了30名参与者进行一项12分钟的警觉性任务。他们被要求在有/无40赫兹RVS背景的情况下辨别侧向三角形目标的方向。结果发现，40赫兹RVS减轻了随着任务时间增加感知敏感性的下降，这是警觉性下降对行为造成的典型负面影响。脑电图（EEG）结果表明，40赫兹RVS可以减少任务进行过程中前额叶皮层（PFC）刺激后θ波段试验间相干性（ITC）的显著下降。回归分析进一步表明，前额叶θ波段ITC与感知敏感性呈显著正相关。这些发现表明，对视觉皮层的伽马闪烁对远距离PFC区域的低频EEG反应具有跨频率神经调节作用。此外，本研究为4Hz RVS的神经效应提供了新的见解，这可能会影响任务时间对警觉行为的影响，并改变注意力资源的利用。
在线版本包含可在10.1007/s11571-023-10008-6获取的补充材料。
