Parkins C W
Neurosurgery. 1985 Jun;16(6):853-65. doi: 10.1227/00006123-198506000-00025.
The field of cochlear prostheses is reviewed, emphasizing the neurophysiological principles necessary for the development of a successful cochlear prosthesis. Pertinent auditory physiology is reviewed, and four conditions are proposed which, if met, should result in speech recognition by the patient with an implant. These conditions are: The surviving neural population must be adequate over the frequency distribution required to deliver the necessary information for speech discrimination. The central neural processing pattern for decoding and recognizing speech must have been established and still persist. The processing of the acoustic signal by the auditory system up to the level of the prosthesis interface must be understood and predictable from the acoustic stimulus. The relationship between the response patterns of the neural elements and the electrical stimulus must be well documented and controllable. The degree to which these conditions can presently be met is discussed, with some suggestions for future development. The function of the cochlear prosthesis is separated into a signal processing section and an electrical stimulus section. Two signal processing strategies are analog processing of the acoustic signal and speech feature extraction from the acoustic signal. Four possible electrical stimulation strategies are direct analog stimulation from the signal processor, pulse amplitude modulation, pulse width modulation, and stimulation designed to optimize the neural responses to electrical stimulation. Some of the present generation cochlear prostheses, including five approved by the FDA as investigational devices, are discussed according to this classification. The clinical results of testing these devices as aids to lip reading and as stand-alone speech reception aids are compared. All are a potential aid to lip reading. Some prosthesis designs have been implanted in patients who then showed exceptional open set speech discrimination. These exceptional patients have used both single channel and multichannel devices and devices with both analog processing and speech feature extraction strategies. These results are encouraging. More consistent and better speech reception is anticipated for the future as this field develops.
本文对人工耳蜗领域进行了综述，重点强调了成功开发人工耳蜗所需的神经生理学原理。回顾了相关的听觉生理学，并提出了四个条件，若能满足这些条件，植入人工耳蜗的患者应能实现言语识别。这些条件是：在传递语音辨别所需信息的频率分布范围内，存活的神经群体必须足够。用于解码和识别语音的中枢神经处理模式必须已经建立且仍然存在。必须了解听觉系统对声信号的处理过程，直至假体接口水平，并且能够从声刺激中预测出来。神经元件的反应模式与电刺激之间的关系必须有充分的记录且可控。文中讨论了目前满足这些条件的程度，并对未来发展提出了一些建议。人工耳蜗的功能分为信号处理部分和电刺激部分。两种信号处理策略是对声信号进行模拟处理以及从声信号中提取语音特征。四种可能的电刺激策略是直接从信号处理器进行模拟刺激、脉冲幅度调制、脉冲宽度调制以及旨在优化神经对电刺激反应的刺激方式。根据这种分类，讨论了一些当代的人工耳蜗，包括美国食品药品监督管理局（FDA）批准作为研究性器械的五种产品。比较了将这些器械作为唇读辅助工具和独立语音接收辅助工具进行测试的临床结果。所有这些器械都有可能辅助唇读。一些假体设计已植入患者体内，这些患者随后表现出了出色的开放集言语辨别能力。这些特殊患者使用过单通道和多通道设备，以及采用模拟处理和语音特征提取策略的设备。这些结果令人鼓舞。随着该领域的发展，预计未来语音接收将更加一致且更好。
