Biomedical subjects

K L Payton

Publications and source records attributed to K L Payton.

3 recordsLinked to original sources

PubMed1999

A method to determine the speech transmission index from speech waveforms.

A method for computing the speech transmission index (STI) using real speech stimuli is presented and evaluated. The method reduces the effects of some of the artifacts that can be encountered when speech waveforms are used as probe stimuli. Speech-based STIs are computed for conversational and clearly articulated speech in several noisy, reverberant, and noisy-reverberant environments and compared with speech intelligibility scores. The results indicate that, for each speaking style, the speech-based STI values are monotonically related to intelligibility scores for the degraded speech conditions tested. Therefore, the STI can be computed using speech probe waveforms and the values of the resulting indices are as good predictors of intelligibility scores as those derived from MTFs by theoretical methods.

Electronic Data Processing↗

PubMed1994

Intelligibility of conversational and clear speech in noise and reverberation for listeners with normal and impaired hearing.

The effect of articulating clearly on speech intelligibility is analyzed for ten normal-hearing and two hearing-impaired listeners in noisy, reverberant, and combined environments. Clear speech is more intelligible than conversational speech for each listener in every environment. The difference in intelligibility due to speaking style increases as noise and/or reverberation increase. The average difference in intelligibility is 20 percentage points for the normal-hearing listeners and 26 percentage points for the hearing-impaired listeners. Two predictors of intelligibility are used to quantify the environmental degradations: The articulation index (AI) and the speech transmission index (STI). Both are shown to predict, reliably, performance levels within a speaking style for normal-hearing listeners. The AI is unable to represent the reduction in intelligibility scores due to reverberation for the hearing-impaired listeners. Neither predictor can account for the difference in intelligibility due to speaking style.

Adult↗

PubMed1988

Vowel processing by a model of the auditory periphery: a comparison to eighth-nerve responses.

A model of peripheral auditory processing that incorporates processing steps describing the conversion from the acoustic pressure-wave signal at the eardrum to the time course activity in auditory neurons has been developed. It can process arbitrary time domain waveforms and yield the probability of neural firing. The model consists of a concatenation of modules, one for each anatomical section of the periphery. All modules are based on published algorithms and current experimental data, except that the basilar membrane is assumed to be linear. The responses of this model to vowels alone and vowels in noise are compared to neural population responses, as determined by the temporal and average rate response measures of Sachs and Young [J. Acoust. Soc. Am. 66, 470-479, (1979)] and Young and Sachs [J. Acoust. Soc. Am. 66, 1381-1403, (1979)]. Despite the exclusion of nonlinear membrane mechanics, the model accurately predicts the vowel formant representations in the average localized synchronized rate (ALSR) responses and the saturating characteristics of the normalized average rate responses in quiet. When vowels are presented in background noise, the modeled ALSR responses are less robust than the neural data.

Basilar Membrane↗