Auditory steady-state evoked potentials (SS-EPs) are phase-locked neural responses to periodic stimuli, believed to reflect specific neural generators. As an objective measure, steady-state responses have been used in different clinical settings, including measuring hearing thresholds of normal and hearing-impaired subjects. Recent studies are in favor of recording these responses as a part of the cochlear implant (CI) device-fitting procedure. Considering these potential benefits, the goals of the present study were to assess the feasibility of recording free-field SS-EPs in CI users and to compare their characteristics between CI users and controls. By taking advantage of a recently developed dual-frequency tagging method, we attempted to record subcortical and cortical SS-EPs from adult CI users and controls and measured reliable subcortical and cortical SS-EPs in the control group. Independent component analysis (ICA) was used to remove CI stimulation artifacts, yet subcortical responses of several CIs were heavily contaminated by these artifacts. Consequently, only cortical SS-EPs were compared between groups, which were found to be larger in the controls. The lower cortical SS-EPs’ amplitude in CI users might indicate a reduction in neural synchrony evoked by the modulation rate of the auditory input across different neural assemblies in the auditory pathway. The brain topographies of cortical auditory SS-EPs, the time course of cortical responses, and the reconstructed cortical maps were highly similar between groups, confirming their neural origin and possibility to obtain such responses also in CI recipients. As for subcortical SS-EPs, our results highlight a need for sophisticated denoising algorithms to pinpoint and remove artifactual components from the biological response.

听觉稳态诱发电位 (SS-EP) 是对周期性刺激的锁相神经反应，据信反映了特定的神经发生器。作为客观测量，稳态响应已用于不同的临床环境，包括测量正常和听力受损受试者的听力阈值。最近的研究支持将这些反应记录为人工耳蜗 (CI) 设备装配程序的一部分。考虑到这些潜在的好处，本研究的目标是评估在 CI 用户中记录自由场 SS-EP 的可行性，并比较 CI 用户和对照组之间的特征。通过利用最近开发的双频标记方法，我们试图记录成年 CI 用户和对照组的皮层下和皮层 SS-EP，并测量对照组中可靠的皮层下和皮层 SS-EP。独立成分分析 (ICA) 用于去除 CI 刺激伪影，但几个 CI 的皮层下反应被这些伪影严重污染。因此，只比较了组间的皮质 SS-EP，发现对照组中的皮质 SS-EP 更大。CI 用户中较低的皮质 SS-EP 振幅可能表明由听觉通路中不同神经组件的听觉输入的调制率引起的神经同步性降低。皮层听觉 SS-EP 的大脑地形图、皮层反应的时间过程和重建的皮层图在各组之间高度相似，确认他们的神经起源和在 CI 接受者中也获得此类反应的可能性。至于皮层下 SS-EP，我们的结果强调需要复杂的去噪算法来从生物反应中查明和去除人为成分。