Tognola G, Grandori F, Ravazzani P
System Theory Centre-CNR, Department of Biomedical Engineering, Milan, Italy.
Hear Res. 1997 Apr;106(1-2):112-22. doi: 10.1016/s0378-5955(97)00007-5.
Emissions evoked by broad-band stimuli, such as clicks, show a 'frequency dispersion' reminiscent of the place-frequency distribution along the cochlea. Analysis of the time-frequency properties of transiently evoked otoacoustic emissions (TEOAEs) is therefore of considerable interest due to their close relation with cochlear mechanisms. In particular, since OAEs in response to click stimuli are expected to evoke a cumulative response from the whole cochlea, the analysis of click-evoked OAEs can yield a global view of cochlear function. Wavelet analysis is performed to obtain time-frequency distributions of click-evoked OAEs at various intensity levels from normal ears. By means of the inverse wavelet transform, the recorded responses are decomposed into elementary components representing the contribution within a narrow frequency band to the cumulative OAE. The relationship between the frequency of the elementary components, latency and level of stimulation is described.
由宽带刺激（如短声）诱发的耳声发射呈现出一种“频率弥散”，这让人联想到沿耳蜗的位置-频率分布。因此，由于瞬态诱发耳声发射（TEOAEs）与耳蜗机制密切相关，对其时间-频率特性进行分析具有相当重要的意义。特别是，由于预期对短声刺激的耳声发射会诱发整个耳蜗的累积反应，所以对短声诱发耳声发射的分析可以提供耳蜗功能的整体视图。对正常耳在不同强度水平下短声诱发耳声发射进行小波分析，以获得其时间-频率分布。通过小波逆变换，将记录的反应分解为代表窄频带内对累积耳声发射贡献的基本成分。描述了基本成分的频率、潜伏期和刺激水平之间的关系。
