Data from: Contralateral noise stimulation delays P300 latency in school-aged children

Background and objective: The auditory cortex modulates auditory afferents through the olivocochlear system, which innervates the outer hair cells and the afferent neurons under the inner hair cells in the cochlea. Most of the studies that investigated the efferent activity in humans focused on evaluating the suppression of the otoacoustic emissions by stimulating the contralateral ear with noise, which assesses the activation of the medial olivocochlear bundle. The neurophysiology and the mechanisms involving efferent activity on higher regions of the auditory pathway, however, are still unknown. Also, the lack of studies investigating the effects of noise on human auditory cortex, especially in peadiatric population, points to the need for recording the late auditory potentials in noise conditions. Assessing the auditory efferents in schoolaged children is highly important due to some of its attributed functions such as selective attention and signal detection in noise, which are important abilities related to the development of language and academic skills. For this reason, the aim of the present study was to evaluate the effects of noise on P300 responses of children with normal hearing. Methods: P300 was recorded in 27 children aged from 8 to 14 years with normal hearing in two conditions: with and whitout contralateral white noise stimulation. Results: P300 latencies were significantly longer at the presence of contralateral noise. No significant changes were observed for the amplitude values. Conclusion: Contralateral white noise stimulation delayed P300 latency in a group of school-aged children with normal hearing. These results suggest a possible influence of the medial olivocochlear activation on P300 responses under noise condition.背景与目的：听觉皮层（auditory cortex）可通过橄榄耳蜗系统（olivocochlear system）调控听觉传入通路，该系统支配耳蜗内的外毛细胞（outer hair cells）以及内毛细胞（inner hair cells）下方的传入神经元。既往针对人类传出活动（efferent activity）的研究大多通过噪声刺激对侧耳，评估耳声发射（otoacoustic emissions）的抑制效应，以此评价内侧橄榄耳蜗束（medial olivocochlear bundle）的激活状态。然而，涉及听觉通路（auditory pathway）更高层级区域传出活动的神经生理学（neurophysiology）机制仍未明确。此外，目前缺乏针对噪声对人类听觉皮层影响的研究，尤其是儿科人群（pediatric population），这凸显了在噪声条件下记录迟发性听觉电位（late auditory potentials）的必要性。由于学龄儿童（school-aged children）的听觉传出系统具备选择性注意（selective attention）、噪声环境下信号检测（signal detection）等与语言发育及学业技能（academic skills）发展密切相关的功能，因此对其进行评估具有重要意义。基于此，本研究旨在评估噪声对正常听力儿童P300反应的影响。方法：本研究纳入27名8~14岁、听力正常的儿童，分别在有对侧白噪声刺激（contralateral white noise stimulation）与无对侧白噪声刺激两种条件下记录P300。结果：对侧噪声存在时P300潜伏期显著延长，而波幅未出现明显变化。结论：对侧白噪声刺激可使正常听力学龄儿童的P300潜伏期延迟。上述结果提示，在噪声条件下，内侧橄榄耳蜗束的激活可能对P300反应存在调控作用。