Erratum: Cognitive disruption by noise-vocoded speech stimuli: Effects of spectral variation [J. Acoust. Soc. Am. 143(3), 1407–1416 (2018)]

AbstractWhilst functional neuroimaging has been used to investigate cortical processing of degraded speech in adults, much less is known about how these signals are processed in children. An enhanced understanding of cortical correlates of poor speech perception in children would be highly valuable to oral communication applications, including hearing devices. We utilised vocoded speech stimuli to investigate brain responses to degraded speech in 29 normally hearing children aged 6–12 years. Intelligibility of the speech stimuli was altered in two ways by (i) reducing the number of spectral channels and (ii) reducing the amplitude modulation depth of the signal. A total of five different noise-vocoded conditions (with zero, partial or high intelligibility) were presented in an event-related format whilst participants underwent functional near-infrared spectroscopy (fNIRS) neuroimaging. Participants completed a word recognition task during imaging, as well as a separate behavioural speech perception assessment. fNIRS recordings revealed statistically significant sensitivity to stimulus intelligibility across several brain regions. More intelligible stimuli elicited stronger responses in temporal regions, predominantly within the left hemisphere, while right inferior parietal regions showed an opposite, negative relationship. Although there was some evidence that partially intelligible stimuli elicited the strongest responses in the left inferior frontal cortex, a region previous studies have suggested is associated with effortful listening in adults, this effect did not reach statistical significance. These results further our understanding of cortical mechanisms underlying successful speech perception in children. Furthermore, fNIRS holds promise as a clinical technique to help assess speech intelligibility in paediatric populations.

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Perceptual Learning of Vocoded Speech With and Without Contralateral Hearing: Implications for Cochlear Implant Rehabilitation

Journal of Speech Language and Hearing Research ◽

10.1044/2020_jslhr-20-00385 ◽

2020 ◽

pp. 1-10

Author(s):

Martin Chavant ◽

Alexis Hervais-Adelman ◽

Olivier Macherey

Keyword(s):

Cochlear Implant ◽

Perceptual Learning ◽

Speech Signal ◽

Training Phase ◽

Monosyllabic Words ◽

Low Pass ◽

Contralateral Ear ◽

Number Of Individuals ◽

Insight Into ◽

Vocoded Speech

Purpose An increasing number of individuals with residual or even normal contralateral hearing are being considered for cochlear implantation. It remains unknown whether the presence of contralateral hearing is beneficial or detrimental to their perceptual learning of cochlear implant (CI)–processed speech. The aim of this experiment was to provide a first insight into this question using acoustic simulations of CI processing. Method Sixty normal-hearing listeners took part in an auditory perceptual learning experiment. Each subject was randomly assigned to one of three groups of 20 referred to as NORMAL, LOWPASS, and NOTHING. The experiment consisted of two test phases separated by a training phase. In the test phases, all subjects were tested on recognition of monosyllabic words passed through a six-channel “PSHC” vocoder presented to a single ear. In the training phase, which consisted of listening to a 25-min audio book, all subjects were also presented with the same vocoded speech in one ear but the signal they received in their other ear differed across groups. The NORMAL group was presented with the unprocessed speech signal, the LOWPASS group with a low-pass filtered version of the speech signal, and the NOTHING group with no sound at all. Results The improvement in speech scores following training was significantly smaller for the NORMAL than for the LOWPASS and NOTHING groups. Conclusions This study suggests that the presentation of normal speech in the contralateral ear reduces or slows down perceptual learning of vocoded speech but that an unintelligible low-pass filtered contralateral signal does not have this effect. Potential implications for the rehabilitation of CI patients with partial or full contralateral hearing are discussed.

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Functional Magnetic Resonance Imaging Measures of Blood Flow Patterns in the Human Auditory Cortex in Response to Sound

Journal of Speech Language and Hearing Research ◽

10.1044/jslhr.4103.538 ◽

1998 ◽

Vol 41 (3) ◽

pp. 538-548 ◽

Cited By ~ 7

Author(s):

Sean C. Huckins ◽

Christopher W. Turner ◽

Karen A. Doherty ◽

Michael M. Fonte ◽

Nikolaus M. Szeverenyi

Keyword(s):

Magnetic Resonance Imaging ◽

Blood Flow ◽

Magnetic Resonance ◽

Functional Magnetic Resonance Imaging ◽

Functional Magnetic Resonance ◽

Resonance Imaging ◽

Speech Stimuli ◽

Complex Stimuli ◽

Scanning Session ◽

Auditory Research

Functional Magnetic Resonance Imaging (fMRI) holds exciting potential as a research and clinical tool for exploring the human auditory system. This noninvasive technique allows the measurement of discrete changes in cerebral cortical blood flow in response to sensory stimuli, allowing determination of precise neuroanatomical locations of the underlying brain parenchymal activity. Application of fMRI in auditory research, however, has been limited. One problem is that fMRI utilizing echo-planar imaging technology (EPI) generates intense noise that could potentially affect the results of auditory experiments. Also, issues relating to the reliability of fMRI for listeners with normal hearing need to be resolved before this technique can be used to study listeners with hearing loss. This preliminary study examines the feasibility of using fMRI in auditory research by performing a simple set of experiments to test the reliability of scanning parameters that use a high resolution and high signal-to-noise ratio unlike that presently reported in the literature. We used consonant-vowel (CV) speech stimuli to investigate whether or not we could observe reproducible and consistent changes in cortical blood flow in listeners during a single scanning session, across more than one scanning session, and in more than one listener. In addition, we wanted to determine if there were differences between CV speech and nonspeech complex stimuli across listeners. Our study shows reproducibility within and across listeners for CV speech stimuli. Results were reproducible for CV speech stimuli within fMRI scanning sessions for 5 out of 9 listeners and were reproducible for 6 out of 8 listeners across fMRI scanning sessions. Results of nonspeech complex stimuli across listeners showed activity in 4 out of 9 individuals tested.

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Noise-Vocoded Speech Contexts Produce the Irrelevant Sound Effect

PsycEXTRA Dataset ◽

10.1037/e633262013-438 ◽

2013 ◽

Keyword(s):

Sound Effect ◽

Irrelevant Sound ◽

Irrelevant Sound Effect ◽

Vocoded Speech

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New possibility for measuring the cortical auditory evoked potentials: the HEARLab

Orvosi Hetilap ◽

10.1556/oh.2014.29992 ◽

2014 ◽

Vol 155 (38) ◽

pp. 1524-1529

Author(s):

Ádám Bach ◽

Ferenc Tóth ◽

Vera Matievics ◽

József Géza Kiss ◽

József Jóri ◽

...

Keyword(s):

Clinical Practice ◽

Evoked Potentials ◽

Auditory System ◽

Hearing Aids ◽

Pure Tone ◽

Auditory Evoked Potentials ◽

Normal Hearing ◽

Speech Stimuli ◽

Novel Method ◽

Cortical Auditory Evoked Potentials

Introduction: Cortical auditory evoked potentials can provide objective information about the highest level of the auditory system. Aim: The purpose of the authors was to introduce a new tool, the “HEARLab” which can be routinely used in clinical practice for the measurement of the cortical auditory evoked potentials. In addition, they wanted to establish standards of the analyzed parameters in subjects with normal hearing. Method: 25 adults with normal hearing were tested with speech stimuli, and frequency specific examinations were performed utilizing pure tone stimuli. Results: The findings regarding the latency and amplitude analyses of the evoked potentials confirm previously published results of this novel method. Conclusions: The HEARLAb can be a great help when performance of the conventional audiological examinations is complicated. The examination can be performed in uncooperative subjects even in the presence of hearing aids. The test is frequency specific and does not require anesthesia. Orv. Hetil., 2014, 155(38), 1524–1529.

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The Spatial Selective Auditory Attention of Cochlear Implant Users in Different Conversational Sound Levels

Journal of Clinical Medicine ◽

10.3390/jcm10143078 ◽

2021 ◽

Vol 10 (14) ◽

pp. 3078

Author(s):

Sara Akbarzadeh ◽

Sungmin Lee ◽

Chin-Tuan Tan

Keyword(s):

Cochlear Implant ◽

Sound Level ◽

Auditory Attention ◽

Impaired Hearing ◽

Speech Stimuli ◽

Electric Hearing ◽

Sound Levels ◽

Acoustic Hearing ◽

Speech Envelope ◽

Different Levels

In multi-speaker environments, cochlear implant (CI) users may attend to a target sound source in a different manner from normal hearing (NH) individuals during a conversation. This study attempted to investigate the effect of conversational sound levels on the mechanisms adopted by CI and NH listeners in selective auditory attention and how it affects their daily conversation. Nine CI users (five bilateral, three unilateral, and one bimodal) and eight NH listeners participated in this study. The behavioral speech recognition scores were collected using a matrix sentences test, and neural tracking to speech envelope was recorded using electroencephalography (EEG). Speech stimuli were presented at three different levels (75, 65, and 55 dB SPL) in the presence of two maskers from three spatially separated speakers. Different combinations of assisted/impaired hearing modes were evaluated for CI users, and the outcomes were analyzed in three categories: electric hearing only, acoustic hearing only, and electric + acoustic hearing. Our results showed that increasing the conversational sound level degraded the selective auditory attention in electrical hearing. On the other hand, increasing the sound level improved the selective auditory attention for the acoustic hearing group. In the NH listeners, however, increasing the sound level did not cause a significant change in the auditory attention. Our result implies that the effect of the sound level on selective auditory attention varies depending on the hearing modes, and the loudness control is necessary for the ease of attending to the conversation by CI users.

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Hyperspectral Imagery for Assessing Laser-Induced Thermal State Change in Liver

Sensors ◽

10.3390/s21020643 ◽

2021 ◽

Vol 21 (2) ◽

pp. 643

Author(s):

Martina De Landro ◽

Ignacio Espíritu García-Molina ◽

Manuel Barberio ◽

Eric Felli ◽

Vincent Agnus ◽

...

Keyword(s):

Thermal Damage ◽

Thermal State ◽

Preliminary Investigation ◽

Spectral Band ◽

Spectral Variation ◽

Ablation Therapy ◽

Clinical Endpoints ◽

Breathing Motion ◽

Living Tissues

This work presents the potential of hyperspectral imaging (HSI) to monitor the thermal outcome of laser ablation therapy used for minimally invasive tumor removal. Our main goal is the establishment of indicators of the thermal damage of living tissues, which can be used to assess the effect of the procedure. These indicators rely on the spectral variation of temperature-dependent tissue chromophores, i.e., oxyhemoglobin, deoxyhemoglobin, methemoglobin, and water. Laser treatment was performed at specific temperature thresholds (from 60 to 110 °C) on in-vivo animal liver and was assessed with a hyperspectral camera (500–995 nm) during and after the treatment. The indicators were extracted from the hyperspectral images after the following processing steps: the breathing motion compensation and the spectral and spatial filtering, the selection of spectral bands corresponding to specific tissue chromophores, and the analysis of the areas under the curves for each spectral band. Results show that properly combining spectral information related to deoxyhemoglobin, methemoglobin, lipids, and water allows for the segmenting of different zones of the laser-induced thermal damage. This preliminary investigation provides indicators for describing the thermal state of the liver, which can be employed in the future as clinical endpoints of the procedure outcome.

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