Transcranial alternating current stimulation (tACS) is a type of noninvasive brain stimulation technique that has been shown to modulate motor, cognitive and memory function. Direct electrophysiological evidence of an interaction between tACS and the auditory cortex excitability has rarely been reported. Different stimulation parameters and areas of tACS may have different influence on the regulatory results. In this study, 11-Hz tACS was applied to the auditory cortex of 12 subjects with normal hearing in order to explore its effects on the auditory steady-state response (ASSR). The results indicate that tACS has an inhibitory effect on 40-Hz ASSR. In addition, EEG source analysis shows that 11-Hz tACS may enhance the activity of the middle temporal gyrus under both sham and real conditions, while the estimated source activity of the posterior cingulate gyrus may be reduced under real condition. The results reveal that tACS applied to the temporal lobe of humans will make the 40-Hz ASSR a tendency to decrease, and help improve the understanding of modulation of tACS-induced auditory cortex excitability changes in humans.

经颅交流电刺激（tACS）是一种非侵入性脑刺激技术，已被证明可调节运动，认知和记忆功能。tACS和听觉皮层兴奋性之间相互作用的直接电生理证据鲜有报道。tACS的不同刺激参数和面积可能对调节结果有不同的影响。在这项研究中，将11 Hz tACS应用于听力正常的12名受试者的听觉皮层，以探讨其对听觉稳态反应（ASSR）的影响。结果表明，tACS对40 Hz ASSR具有抑制作用。此外，EEG信号源分析表明，在假想和真实条件下，11 Hz tACS均可增强颞中回的活动，而在实际情况下，后扣带回的估计源活动可能会减少。结果表明，将tACS应用于人类颞叶将使40 Hz ASSR降低，并有助于增进对tACS诱导的人类听觉皮层兴奋性变化的调节的了解。