Neuropsychology Lab, Department of Psychology, European Medical School, University of Oldenburg, Oldenburg, Germany.
Neuropsychology Lab, Department of Psychology, European Medical School, University of Oldenburg, Oldenburg, Germany.
Neuroimage. 2017 Feb 1;146:600-608. doi: 10.1016/j.neuroimage.2016.09.033. Epub 2016 Sep 15.
Previous studies have observed lower visual cortex activation for visual processing in cochlear implant (CI) users compared to normal hearing controls, while others reported enhanced visual speechreading abilities in CI users. The present work investigated whether lower visual cortical activation for visual processing can be explained by a more efficient visual sensory encoding in CI users. Specifically, we investigated whether CI users show enhanced stimulus-specific adaptation for visual stimuli compared to controls. Auditory sensory adaptation was also investigated to explore the sensory specificity of the predicted effect. Twenty post-lingually deafened adult CI users and twenty age-matched controls were presented with repeated visual and auditory stimuli during simultaneous acquisition of electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS). By integrating EEG and fNIRS signals we found significantly enhanced visual adaptation and lower visual cortex activation in CI users compared to controls. That is, responses to repeated visual stimuli decreased more prominently in CI users than in controls. The results suggest that CI users process visual stimuli more efficiently than controls.
先前的研究观察到，与正常听力对照组相比，人工耳蜗（CI）使用者的视觉皮层对视觉处理的激活程度较低，而另一些研究则报告称 CI 使用者的视觉言语阅读能力增强。本研究旨在探讨视觉处理中较低的视觉皮层激活是否可以通过 CI 用户更有效的视觉感觉编码来解释。具体来说，我们研究了 CI 用户是否比对照组对视觉刺激表现出更强的刺激特异性适应。还研究了听觉感觉适应，以探索预测效果的感觉特异性。在同时获取脑电图（EEG）和功能近红外光谱（fNIRS）期间，我们对 20 名后天失聪的成年 CI 用户和 20 名年龄匹配的对照组进行了重复的视觉和听觉刺激呈现。通过整合 EEG 和 fNIRS 信号，我们发现 CI 用户的视觉适应明显增强，视觉皮层激活降低。也就是说，CI 用户对重复的视觉刺激的反应比对照组更明显地减少。研究结果表明，CI 用户比对照组更有效地处理视觉刺激。
