Search

The speech auditory brainstem response (sABR) is a promising tool that can be used for objectively assessing auditory function. The main problem in obtaining the sABR is the high background noise, especially noise associated with general brain activity. In practice, a very long recording is needed to detect the sABR. We therefore propose a new detection method of the sABR based on spectral feature extraction that will reduce the detection time without reducing the accuracy. This method involves a constructed feature-frequency vector fed to an artificial neural network. The performance of the proposed method is compared to four other methods reported in the literature: optimal linear filtering, online estimator, Mutual Information, and artificial neural network based on discrete wavelet transforms and approximate entropy. All the methods were evaluated with several datasets of recorded and simulated sABRs ranging from extremely noisy to relatively clean. The proposed method performed very well in terms of sensitivity, specificity, and overall accuracy in detecting the sABR, compared with the other methods The reduction in the required recording time promises to facilitate the application of this measurement technique in clinical settings. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Speech-Language Pathology & Audiology is the property of Speech-Language & Audiology Canada and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Lung-to-finger circulation time of oxygenated blood during nocturnal periodic breathing in heart failure patients measured using polysomnography correlates negatively with cardiac function but possesses limited accuracy for cardiac output (CO) estimation.Methods and Results: CO was recalculated from lung-to-finger circulation time using a multivariable linear model with information on age and average overnight heart rate in 25 patients who underwent evaluation of heart failure. The multivariable model decreased the percentage error to 22.3% relative to invasive CO measured during cardiac catheterization.Conclusions: This improved automated noninvasive CO estimation using multiple variables meets a recently proposed performance criterion for clinical acceptability of noninvasive CO estimation, and compares very favorably with other available methods. [ABSTRACT FROM AUTHOR]

Summary: Objectives: Objective acoustic measures used to analyze phonatory dysfunction include shimmer and jitter. These measures are limited in that they do not take into account auditory processing. However, previous studies have indicated that shimmer may be processed differently along the tonotopic axis of the ear and, in particular, may be perceptually and physiologically significant around the third and fourth formants. Methods: This study investigated the relationship between shimmer around the first four formants (F1–F4) and in the broadband unfiltered speech waveform for 18 normal speakers from the voice disorders database of KayPENTAX. The voice samples were filtered around each formant with a bandwidth of 400Hz and then shimmer was assessed using five built-in different measures from Praat software. Results: Comparisons of means tests revealed that shimmer increases significantly with formant frequency from F1 to F4, for all shimmer measures. Furthermore, for all shimmer measures, shimmer in the unfiltered speech was significantly and more strongly correlated with shimmer around F1 (r = 0.45–0.61) and F2 (r = 0.69–0.74), significantly but more weakly correlated with F4 (r = 0.42–0.47), and not significantly correlated with F3. Conclusions: The findings indicate that there are differences in the shimmer found around the different formants and that shimmer information around F3 and F4 is not well captured in standard shimmer measurements based on the broadband unfiltered waveform. [Copyright &y& Elsevier]

The measurement of sound exposure for individuals using communication headsets and headphones in the workplace imposes many technical challenges, and it has been difficult to integrate such measurements in national and international standards on occupational noise exposure. This paper reviews existing methods to measure sound exposure directly under listening devices, including the use of specialized acoustic manikins, artificial ears and real-ear procedures, and the associated field logistics and data analysis procedures. An alternative indirect calculation method is proposed that uses the main determinants of exposure as input parameters into the assessment, such as the external noise around the user, the attenuation of the device, and the user's listening signal-to-noise ratio. The advantages and disadvantages of the different methods are discussed. Together, they form the basis for a set of four measurement methods and one calculation method on assessing occupational sound exposure from headsets and headphones under consideration by a technical Working Group of the Canadian Standards Association [ABSTRACT FROM AUTHOR]