Perceptual consequences of disrupted auditory nerve activity
Perceptual consequences of disrupted auditory nerve activity
复制标题
DOI：
10.1152/jn.00985.2004
复制
发表时间：
2005-06-01
影响因子：
2.5
通讯作者：
Starr, A
中科院分区：
文献类型：
--
作者：
Zeng, FG;Kong, YY;Starr, A
在 21 名临床诊断为听神经病 (AN) 的受试者中系统地研究了听神经活动中断的感知后果，这是一种最近定义的疾病，其特征是外毛细胞功能正常，但听神经功能中断。神经学和电物理证据表明，听神经活动中断是由于神经活动不同步或减少或两者兼而有之。心理物理学测量表明，受到干扰的神经活动对强度相关感知的影响很小，例如响度辨别、高频音高辨别以及利用耳间电平差异进行声音定位。相反，中断的神经活动会显着损害与时间相关的感知，例如低频下的音调辨别、时间整合、间隙检测、时间调制检测、向后和向前掩蔽、噪声中的信号检测、双耳节拍以及使用耳间时间差的声音定位。这些知觉结果与耳蜗受损受试者中通常观察到的结果相反，耳蜗受损受试者的强度知觉受损，但考虑到强度知觉受损后，时间处理相对正常。听觉神经病变和耳蜗损伤之间感知后果的这些差异表明在听觉感知中使用不同的神经代码：用于强度处理的次优尖峰计数代码、用于时间处理的同步尖峰代码以及用于频率处理的双工代码。我们还提出了两种基于听觉神经去同步和放电减少的基本生理模型，以成功解释观察到的神经和行为数据。这些方法和措施无法区分这两种 AN 模型，但未来通过人工耳蜗植入对听觉神经进行电刺激的研究可能会有所不同。这些结果不仅显示了神经同步对感官知觉的独特贡献，而且还为更好地诊断和管理人类沟通障碍的转化研究提供了指导。
Perceptual consequences of disrupted auditory nerve activity were systematically studied in 21 subjects who had been clinically diagnosed with auditory neuropathy (AN), a recently defined disorder characterized by normal outer hair cell function but disrupted auditory nerve function. Neurological and electrophysical evidence suggests that disrupted auditory nerve activity is due to desynchronized or reduced neural activity or both. Psychophysical measures showed that the disrupted neural activity has minimal effects on intensity-related perception, such as loudness discrimination, pitch discrimination at high frequencies, and sound localization using interaural level differences. In contrast, the disrupted neural activity significantly impairs timing related perception, such as pitch discrimination at low frequencies, temporal integration, gap detection, temporal modulation detection, backward and forward masking, signal detection in noise, binaural beats, and sound localization using interaural time differences. These perceptual consequences are the opposite of what is typically observed in cochlear-impaired subjects who have impaired intensity perception but relatively normal temporal processing after taking their impaired intensity perception into account. These differences in perceptual consequences between auditory neuropathy and cochlear damage suggest the use of different neural codes in auditory perception: a suboptimal spike count code for intensity processing, a synchronized spike code for temporal processing, and a duplex code for frequency processing. We also proposed two underlying physiological models based on desynchronized and reduced discharge in the auditory nerve to successfully account for the observed neurological and behavioral data. These methods and measures cannot differentiate between these two AN models, but future studies using electric stimulation of the auditory nerve via a cochlear implant might. These results not only show the unique contribution of neural synchrony to sensory perception but also provide guidance for translational research in terms of better diagnosis and management of human communication disorders.