PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Speech Intelligibility”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 199 records · Page 11Linked to original sources

[Determination of oesophageal speech intelligibility using an articulation assessment].

OBJECTIVE: We studied if articulation could determine esophageal speech's intelligibility. MATERIAL AND METHOD: To do so, we proposed 30 subjects distributed in three groups based on their speech proficiency level, two preliminary assessments: an articulation assessment and an intelligibility assessment. RESULTS: The study shows a significantly high correlation (86%) between the results of the articulation assessment and the intelligibility assessment in the whole of group studied. However, we noted differences in correlations according to the level of the subjects: in the novices' group, the percentage reaches 62%, in the medium group, 76%, and in the proficient one: 97%. CONCLUSION: We concluded that if the results of the articulation assessment is very high, intelligibility will be good. On the other hand, if this percentage is moderate, we can't evaluate intelligibility only with the articulation factor.

Aged↗

The use of artificial neural networks to estimate speech intelligibility from acoustic variables: a preliminary analysis.

Previous research has used regression analysis to attempt to predict the intelligibility of hearing-impaired speakers from acoustic speech parameters. Improvement of prediction may be achieved by the use of computerized artificial neural networks to process mathematically the acoustic input variables as part of the intelligibility process. A preliminary scheme for estimating speech intelligibility from acoustic parameters using a neural network is outlined and preliminary data illustrate its use.

Adult↗

Speech intelligibility with helicopter noise: tests of three helmet-mounted communication systems.

BACKGROUND: Military aviator helmet communications systems are designed to enhance speech intelligibility (SI) in background noise and reduce exposure to harmful levels of noise. Some aviators, over the course of their aviation career, develop noise-induced hearing loss that may affect their ability to perform required tasks. New technology can improve SI in noise for aviators with normal hearing as well as those with hearing loss. METHODS: SI in noise scores were obtained from 40 rotary-wing aviators (20 with normal hearing and 20 with hearing-loss waivers). There were three communications systems evaluated: a standard SPH-4B, an SPH-4B aviator helmet modified with communications earplug (CEP), and an SPH-4B modified with active noise reduction (ANR). RESULTS: Subjects' SI was better in noise with newer technologies than with the standard issue aviator helmet. A significant number of aviators on waivers for hearing loss performed within the range of their normal hearing counterparts when wearing the newer technology. The rank order of perceived speech clarity was 1) CEP, 2) ANR, and 3) unmodified SPH-4B. CONCLUSIONS: To insure optimum SI in noise for rotary-wing aviators, consideration should be given to retrofitting existing aviator helmets with new technology, and incorporating such advances in communication systems of the future. Review of standards for determining fitness to fly is needed.

Adult↗

Binaural speech intelligibility in noise for hearing-impaired listeners.

The effect of head-induced interaural time delay (ITD) and interaural level differences (ILD) on binaural speech intelligibility in noise was studied for listeners with symmetrical and asymmetrical sensorineural hearing losses. The material, recorded with a KEMAR manikin in an anechoic room, consisted of speech, presented from the front (0 degree), and noise, presented at azimuths of 0 degree, 30 degrees, and 90 degrees. Derived noise signals, containing either only ITD or only ILD, were generated using a computer. For both groups of subjects, speech-reception thresholds (SRT) for sentences in noise were determined as a function of: (1) noise azimuth, (2) binaural cue, and (3) an interaural difference in overall presentation level, simulating the effect of a monaural hearing acid. Comparison of the mean results with corresponding data obtained previously from normal-hearing listeners shows that the hearing impaired have a 2.5 dB higher SRT in noise when both speech and noise are presented from the front, and 2.6-5.1 dB less binaural gain when the noise azimuth is changed from 0 degree to 90 degrees. The gain due to ILD varies among the hearing-impaired listeners between 0 dB and normal values of 7 dB or more. It depends on the high-frequency hearing loss at the side presented with the most favorable signal-to-noise (S/N) ratio. The gain due to ITD is nearly normal for the symmetrically impaired (4.2 dB, compared with 4.7 dB for the normal hearing), but only 2.5 dB in the case of asymmetrical impairment. When ITD is introduced in noise already containing ILD, the resulting gain is 2-2.5 dB for all groups. The only marked effect of the interaural difference in overall presentation level is a reduction of the gain due to ILD when the level at the ear with the better S/N ratio is decreased. This implies that an optimal monaural hearing aid (with a moderate gain) will hardly interfere with unmasking through ITD, while it may increase the gain due to ILD by preventing or diminishing threshold effects.

Adolescent↗

Listener judges and the speech intelligibility of deaf children.

Two listener groups, one experienced and the other inexperienced in listening to deaf speakers, were asked to recognize speech sounds in word contexts presented in two modes: auditory only and auditory-visual. In contrast to previous studies, the experienced and inexperienced listener groups performed similarly. The one exception occurred for speech sounds in the final position presented auditory visually where the experienced listeners' performance surpassed that of inexperienced listeners. For both groups, performance in correct phoneme identification was better in the auditory-visual mode of presentation. Furthermore, and interaction between the position-in-word and the mode of stimulus presentation was present in both groups. In the auditory-only task, listeners correctly identified more target phonemes when they were initial rather than final position in a word. With supplemental visual information, listener performance increased our phonemes in both positions within a word, although the increase was greater for final position phonemes.

Adolescent↗

Difficulties with speech intelligibility in noise in spite of a normal pure-tone audiogram.

A group of 15 patients with complaints of having difficulties in understanding speech, especially in noisy surroundings in spite of (nearly) normal pure-tone audiograms, was subjected to a battery of speech-audiometric tests. The results showed that these subjects had a statistically significantly higher speech reception threshold (SRT) for sentences in noise than a reference group of 10 normal-hearing subjects. This difference was most clear for a fluctuating masking noise. In conditions with much reverberation, the patients also proved to be handicapped more than the control group. Binaural hearing gain was equal for both groups. The pathogenesis of the speech-hearing loss is not known, but assessment of the SRT in noise proves to be a valuable asset in objectifying these patients' complaints.

Adult↗

Accuracy of speech intelligibility index predictions for noise-masked young listeners with normal hearing and for elderly listeners with hearing impairment.

This study examined whether the accuracy of Speech Intelligibility Index (SII) predictions is affected by subject age when between-groups auditory sensitivity differences are controlled. SII predictive accuracy was assessed for elderly listeners with hearing impairment (EHI) and for young noise-masked listeners with normal hearing (NMN). SII predictive accuracy was poorer for the EHI subjects than for the NMN subjects across a range of test conditions and stimuli. Speech test redundancy, speech presentation level, signal-to-babble ratio, and babble level also affected SII predictive accuracy. The results suggest that the speech recognition difficulties experienced in noise by elderly listeners do not result solely from reduced auditory sensitivity.

Adult↗

Improvement in speech intelligibility in noise employing an adaptive filter with normal and hearing-impaired subjects.

It is well known that communication in noisy environments with reverberation present is a difficult problem to solve, particularly for the hearing-impaired listener. Two-microphone noise cancelling using an LMS adaptive filter in real time was used to process speech recorded in the presence of speech-spectrum noise at six different signal-to-noise ratios, -8, -4, 0, 4, 8, and 12 dB. Twelve normal-hearing and 11 sensorineural hearing-impaired subjects were tested. Results indicated mean improvement of 37.34 percent for the 12 normal-hearing subjects and 38.3 percent for 5 of the sensorineural hearing-impaired subjects. Individual data for the 5 remaining hearing-impaired subjects revealed severe speech intelligibility deficits when noise and reverberation contaminated the speech signal. It is proposed that rehabilitative audiological assessments include evaluation of an individual's ability to cope with reverberation and noise.

Acoustics↗

Multichannel speech intelligibility and talker recognition using monaural, binaural, and three-dimensional auditory presentation.

In a 3D auditory display, sounds are presented over headphones in a way that they seem to originate from virtual sources in a space around the listener. This paper describes a study on the possible merits of such a display for bandlimited speech with respect to intelligibility and talker recognition against a background of competing voices. Different conditions were investigated: speech material (words/sentences), presentation mode (monaural/binaural/3D), number of competing talkers (1-4), and virtual position of the talkers (in 45 degrees-steps around the front horizontal plane). Average results for 12 listeners show an increase of speech intelligibility for 3D presentation for two or more competing talkers compared to conventional binaural presentation. The ability to recognize a talker is slightly better and the time required for recognition is significantly shorter for 3D presentation in the presence of two or three competing talkers. Although absolute localization of a talker is rather poor, spatial separation appears to have a significant effect on communication. For either speech intelligibility, talker recognition, or localization, no difference is found between the use of an individualized 3D auditory display and a general display.

Acoustic Stimulation↗

Speech intelligibility of young school-aged children in the presence of real-life classroom noise.

We examined the ability of 40 young children (aged five to eight) to understand speech (monosyllables, spondees, trochees, and trisyllables) when listening in a background of real-life classroom noise. All children had some difficulty understanding speech when the noise was at levels found in many classrooms (i.e., 65 dBA). However, at an intermediate (-6 dB SNR) level, kindergarten and grade 1 children had much more difficulty than did older children. All children performed well in quiet, with results being comparable to or slightly better than those reported in previous studies, suggesting that the task was age appropriate and well understood. These results suggest that the youngest children in the school system, whose classrooms also tend to be among the noisiest, are the most susceptible to the effects of noise.

Acoustics↗