Speech Sound Level Research Articles

Value of patient-reported outcome measures for evaluating the benefit of speech processor upgrading in patients with cochlear implants.

Patients with acochlear implant (CI) should be evaluated for anew speech processor every 6years. The aim of this analysis was to assess the subjective and audiological benefit of upgrades. Speech understanding and subjective benefit were analyzed in 99patients with the old and the new speech processor after 4weeks of wearing. Speech understanding was assessed using the Freiburg monosyllabic test in quiet (FBE) at 65 dB and 80 dB, and the Oldenburg Sentence Test (OLSA) at 65 dB noise with adaptive speech sound level. The Abbreviated Profile of Hearing Aid Benefit (APHAB) was used to assess subjective hearing impairment, and the Audio Processor Satisfaction Questionnaire (APSQ) was used to assess subjective satisfaction. The speech processor upgrade resulted in asignificant improvement of speech understanding in quiet at 65 dB (mean difference 8.9 ± 25.9percentage points, p < 0.001) and 80 dB (mean difference 8.1 ± 29.7percentage points, p < 0.001) and in noise (mean difference 3.2 ± 10.7 dBsignal-to-noise ratio [S/N], p = 0.006). Using the APHAB, asignificant improvement (mean difference 0.07 ± 0.16, p < 0.001) in hearing impairment was demonstrated in all listening situations. The APSQ showed significantly higher patient satisfaction with the new speech processor (mean difference 0.42 ± 1.26, p = 0.006).A comparative assessment of the benefit based on subjective and speech audiometric results identified aproportion of patients (35-42%) who subjectively benefited from the upgrade but had no measurable benefit based on speech audiometry. There was asignificant improvement in audiologically measurable and subjectively reflected speech understanding and patient satisfaction after the upgrade. In patients with only asmall improvement in audiologically measurable speech understanding, the subjective benefit should also be assessed with validated measurement instruments in order to justify an upgrade to the payers in the health sector.

Value of patient-reported outcome measures for evaluating the benefit of speech processor upgrading in patients with cochlear implants. German version

Patients with acochlear implant (CI) should be evaluated for anew speech processor every 6years. The aim of this analysis was to assess the subjective and audiological benefit of upgrades. Speech understanding and subjective benefit were analyzed in 99patients with the old and the new speech processor after 4weeks of wearing. Speech understanding was assessed using the Freiburg monosyllabic test in quiet (FBE) at 65 dB and 80 dB, and the Oldenburg Sentence Test (OLSA) at 65 dB noise with adaptive speech sound level. The Abbreviated Profile of Hearing Aid Benefit (APHAB) was used to assess subjective hearing impairment, and the Audio Processor Satisfaction Questionnaire (APSQ) was used to assess subjective satisfaction. The speech processor upgrade resulted in asignificant improvement of speech understanding in quiet at 65 dB (mean difference 8.9 ± 25.9percentage points, p < 0.001) and 80 dB (mean difference 8.1 ± 29.7percentage points, p < 0.001) and in noise (mean difference 3.2 ± 10.7 dBsignal-to-noise ratio [S/N], p = 0.006). Using the APHAB, asignificant improvement (mean difference 0.07 ± 0.16, p < 0.001) in hearing impairment was demonstrated in all listening situations. The APSQ showed significantly higher patient satisfaction with the new speech processor (mean difference 0.42 ± 1.26, p = 0.006).A comparative assessment of the benefit based on subjective and speech audiometric results identified aproportion of patients (35-42%) who subjectively benefited from the upgrade but had no measurable benefit based on speech audiometry. There was asignificant improvement in audiologically measurable and subjectively reflected speech understanding and patient satisfaction after the upgrade. In patients with only asmall improvement in audiologically measurable speech understanding, the subjective benefit should also be assessed with validated measurement instruments in order to justify an upgrade to the payers in the health sector.

The impact of orthographic forms on speech production and perception: An artificial vowel-learning study

This study investigates the effect of orthographic forms on phonetic aspects of isolated speech sound production and perception. Three groups of 25 L1-Spanish speakers were exposed to /y/ and /ɛ/ in a multi-session learning study. They heard the same vowels presented with: L1-incongruent orthographic forms, novel orthographic forms, or without orthographic forms. After three exposure sessions, participants were tested on vowel production in an elicited production task and vowel perception in a multiple forced choice task. All groups established new /y/ and /ɛ/ production and perception categories. Incongruent orthographic forms led to less target-like category positions for /y/ but not /ɛ/ in production and perception. Novel orthographic forms only facilitated more target-like perception for /y/. In a fourth session, Auditory-only participants were exposed to incongruent orthography for /y/ and novel orthography for /ɛ/. Sequential exposure to incongruent orthography caused less target-like production and perception category positions, while sequential exposure to novel orthography altered neither. Together these results suggest that orthographic forms affect isolated speech sounds and are encoded at the speech sound level. Incongruent grapheme-to-phoneme mappings from L1 to later-learned languages may critically affect the phonetic characteristics of non-native speech sounds, but learning outcomes depend on specific L1-L2 category contrasts.

Modeling Speech Level as a Function of Background Noise Level and Talker-to-Listener Distance for Talkers Wearing Hearing Protection Devices.

Studying the variations in speech levels with changing background noise level and talker-to-listener distance for talkers wearing hearing protection devices (HPDs) can aid in understanding communication in background noise. Speech was recorded using an intra-aural HPD from 12 different talkers at 5 different distances in 3 different noise conditions and 2 quiet conditions. This article proposes models that can predict the difference in speech level as a function of background noise level and talker-to-listener distance for occluded talkers. The proposed model complements the existing model presented by Pelegrín-García, Smits, Brunskog, and Jeong (2011) and expands on it by taking into account the effects of occlusion and background noise level on changes in speech sound level. Three models of the relationship between vocal effort, background noise level, and talker-to-listener distance for talkers wearing HPDs are presented. The model with the best prediction intervals is a talker-dependent model that requires the users' unoccluded speech level at 10 m as a reference. A model describing the relationship between speech level, talker-to-listener distance, and background noise level for occluded talkers could eventually be incorporated with radio protocols to transmit verbal communication only to an intended set of listeners within a given spatial range-this range being dependent on the changes in speech level and background noise level.

Teachers' voice parameters and classroom acoustics—A field study and online survey

Many studies have suggested that teachers have a significantly higher rate of voice problems than the general population. In order to better understand the possible influences of room acoustics on different voice parameters, a study has been carried out by London South Bank University which involved measurements of voice parameters for teachers working in classrooms with varying acoustic conditions. Data relating to the voice, including the average speech sound level, fundamental frequency, and phonation percentage, were captured using an Ambulatory Phonation Monitor (APM) which measured directly from skin vibrations in the neck, thereby excluding the effects of other noise sources in the environment. The measured voice parameters were compared with the room acoustic data for the classrooms involved, which were surveyed separately from the voice measurements. In addition to the field measurements, an online questionnaire was undertaken with the support of two UK teacher trade unions. This was designed to gain further information on teachers’ experiences of voice problems and school acoustics in general and indicated that over 66% of the surveyed teachers had experienced voice problems during their career. This paper will present the results of the field measurements and questionnaire survey.

How Classroom Acoustics Affect the Vocal Load of Teachers

In the UK the document BB93 Acoustic Design of Schools provides design guidance for refurbished and new classrooms. Traditionally, school acoustic design in the UK is concerned with the needs of the listener, rather than the voice ergonomics of the speaker. However, a recent survey undertaken by London South Bank University (LSBU) indicated that over 65% of the surveyed teachers had experienced voice problems during their career. This supports other studies suggesting that teachers have a significantly higher incidence of voice problems than the general population.In an effort to better understand the influence of classroom acoustic design on teachers’ speech LSBU is undertaking measurements of teachers’ voices in different classroom types. An Ambulatory Phonation Monitor (APM) is used to measure voice parameters (including the average speech sound level, fundamental frequency and phonation time) directly from the skin vibrations in the neck, thus eliminating the effects of other noise sources in the environment. The rooms involved are acoustically benchmarked separately to enable relationships between the voice data and acoustic parameters, such as unoccupied ambient noise levels and reverberation times, to be investigated. This paper will present the results of the field measurements to date, and discuss some of the findings.

Effects in production of word pre-activation during listening: are listener-generated predictions specified at a speech-sound level?

It has been demonstrated that listener-generated predictions of upcoming material can be specified to a phonological level, such that a specific word onset is anticipated (e.g., DeLong, Urbach, & Kutas, Nature Neuroscience, 8, 1117-1121, 2005). In the present study, we investigated whether such word-form-specific predictions impact picture-naming latencies in a manner similar to that observed when a distractor word is actually presented. Participants were auditorily presented with high-cloze sentence stems, in order to elicit word-form predictions. The pictures for naming were presented immediately following the sentence stem. We systematically manipulated the phonological relationship between the predicted word and the picture name. Across three experiments, naming was facilitated when the picture name fully matched the predicted word. However, naming was neither facilitated nor inhibited when the picture name overlapped phonologically with the predicted word. This finding is in contrast to the knowneffects of phonological overlap when a distractor word is heard or read. Our findings suggest that words that are internally listener-generated (predicted) during comprehension are not robustly specified at a speech-sound (phonological) level.

Phonemic restoration in developmental dyslexia

The comprehension of fluent speech in one's native language requires that listeners integrate the detailed acoustic-phonetic information available in the sound signal with linguistic knowledge. This interplay is especially apparent in the phoneme restoration effect, a phenomenon in which a missing phoneme is “restored” via the influence of top-down information from the lexicon and through bottom-up acoustic processing. Developmental dyslexia is a disorder characterized by an inability to read at the level of one's peers without any clear failure due to environmental influences. In the current study we utilized the phonemic restoration illusion paradigm to examine individual differences in phonemic restoration across a range of reading ability, from very good to dyslexic readers. Results demonstrate that restoration occurs less in those who have high scores on measures of phonological processing. Based on these results, we suggest that the processing or representation of acoustic detail may not be as reliable in poor and dyslexic readers, with the result that lexical information is more likely to override acoustic properties of the stimuli. This pattern of increased restoration could result from a failure of perceptual tuning, in which unstable representations of speech sounds result in the acceptance of non-speech sounds as speech. An additional or alternative theory is that degraded or impaired phonological processing at the speech sound level may reflect architecture that is overly plastic and consequently fails to stabilize appropriately for speech sound representations. Therefore, the inability to separate speech and noise may result as a deficit in separating noise from the acoustic signal.

Acoustic measurement of Shakespeare’s Globe Theatre, London

In the late 1960’s, Sam Wanamaker initiated the reconstruction in London of the theatre built for William Shakespeare’s company of players in the late 16th century. The theatre was built in the traditional manner to be as faithful to the original as surviving documentation allows, and has a circular auditorium with an open roof. The theatre was opened for performances in the summer of 1997. An acoustic survey of the theatre has been carried out. Measurements have been made of reverberation time (RT), early decay time (EDT), clarity index (C50), definition (D50), and rapid speech transmission index (RASTI) within the theatre’s auditorium. Various source positions were chosen on the stage after consultation with voice coaches and actors at the theatre, and receiver positions were chosen to provide uniform coverage of all the major audience areas. The results of these measurements indicate that, despite the theatre’s open-air construction, the amount of early energy provided to most audience areas results in reasonable levels of speech intelligibility, although achieving an adequate speech sound level is more of a problem. This is clearly exacerbated by the theatre’s open-air design, and its position in central London under the main flight path to London’s Heathrow Airport. The reverberant characteristics of the auditorium are generally within acceptable limits for modern theatres.

The effect of changes in hearing status on speech sound level and speech breathing: a study conducted with cochlear implant users and NF-2 patients.

According to a dual-process theory of the role of hearing in speech production, hearing helps maintain an internal model used by the speech control mechanism to achieve phonemic goals. It also monitors the acoustic environment and guides relatively rapid adjustments in postural parameters, such as those underlying average speech sound level and rate, in order to achieve suprasegmental goals that are a compromise between intelligibility and economy of effort. In order to obtain evidence bearing on this theory, acoustic and aerodynamic measures were collected from seven adventitiously deaf speakers who received cochlear implants, three speakers who had severe reduction in hearing following surgery for Neurofibromatosis-2, and one hard of hearing speaker. These speakers made recordings of the Rainbow Passage and an English vowel inventory before and after intervention. All but one of the postlingually deaf speakers who received prosthetic hearing reduced speech sound level, SPL. Three of these significantly increased a measure of inferred glottal aperture, H1-H2, and their session means for these two parameters were inversely correlated longitudinally. All but one of the speakers terminated respiratory limbs closer to functional residual capacity (FRC) once prosthetic hearing was supplied. Finally, the implant users' average values of air expenditure moved toward normative values with prosthetic hearing. These results are attributed to the mediation of changes in respiratory and glottal posture aimed at reducing speech sound level and economizing effort.

透過音の主観評価に関する実験的検討

This study investigates evaluation of speech sound through walls. In this case, it is nesessary to consider the effects of background noise. This paper describes the results of subjective evaluation in different background noise level. The results of this paper are as follows; 1. Transmitted speech sound level is better for index of this purpose than sound pressunre level difference. 2. Level difference between transmitted speech sound level and background noise level is related to the results of subjective evalution.

Spelling performance of children with developmental verbal dyspraxia.

The ability of four children with developmental verbal dyspraxia to imitate, spell, read and copy regular single-syllable words was investigated. The children were found to have more difficulty in spelling and reading these words than a group of children with normal speech who were matched for reading age. It is suggested that 'dyspraxic' children are subject to a phonetic spelling deficit which arises because of a difficulty in segmenting words at a speech-sound level.

Studies on masking audiometry

(1) Authors have already published the paper on the masking of speech (one syllable 100 words list) by white noise, and found the relation between the rate of right answers concerning the word articulation and the fixed ratio of noise to speech sound. The result suggested that the fixed combination of sound and noise levels produced the fixed rate of right answers to the word discrimination test.(2) To qualify the relation between the ratio (speech sound to noise) and the word articulation test. The following experiments were administered concerning the combination of noise and speech sound level which produced the fixed result of word articulation test.The output from the recorded tape of one syllable 100 words list was converted to analogous power using A-D converter and analysed the spectrum.The spectrum of the masking noise was also analysed in the same way as the speech sound.(3) The following results were obtained.The sound levels of the second and the third formant were lower than the first. At the combination which gave the low right answer rate of speech articulation, the sound level of the third formant was near the same level as the back ground noise.These results suggest that the loud speaker which responds well to the sound of high frequency should be employed on the noisy condition.

Speech: Behavior of Middle Ear Muscle during Stuttering

Behavior of the middle ear muscle during speaking was observed in five stutterers by means of the Zwislocki acoustic impedance bridge. Change in impedance did not always parallel precisely the changes in speech sound level. Impedance changed during the initiation and during the course of the stuttering block.