Πέμπτη 27 Ιουλίου 2017
Electrophysiological Evidence for the Sources of the Masking Level Difference
Purpose
The purpose of this review article is to review evidence from auditory evoked potential studies to describe the contributions of the auditory brainstem and cortex to the generation of the masking level difference (MLD).
Method
A literature review was performed, focusing on the auditory brainstem, middle, and late latency responses used in protocols similar to those used to generate the behavioral MLD.
Results
Temporal coding of the signals necessary for generating the MLD occurs in the auditory periphery and brainstem. Brainstem disorders up to wave III of the auditory brainstem response (ABR) can disrupt the MLD. The full MLD requires input to the generators of the auditory late latency potentials to produce all characteristics of the MLD; these characteristics include threshold differences for various binaural signal and noise conditions. Studies using central auditory lesions are beginning to identify the cortical effects on the MLD.
Conclusions
The MLD requires auditory processing from the periphery to cortical areas. A healthy auditory periphery and brainstem codes temporal synchrony, which is essential for the ABR. Threshold differences require engaging cortical function beyond the primary auditory cortex. More studies using cortical lesions and evoked potentials or imaging should clarify the specific cortical areas involved in the MLD.from #Audiology via xlomafota13 on Inoreader http://ift.tt/2uD5Qhs
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Influences of Phonological Context on Tense Marking in Spanish–English Dual Language Learners
Purpose
The emergence of tense-morpheme marking during language acquisition is highly variable, which confounds the use of tense marking as a diagnostic indicator of language impairment in linguistically diverse populations. In this study, we seek to better understand tense-marking patterns in young bilingual children by comparing phonological influences on marking of 2 word-final tense morphemes.
Method
In spontaneous connected speech samples from 10 Spanish–English dual language learners aged 56–66 months (M = 61.7, SD = 3.4), we examined marking rates of past tense -ed and third person singular -s morphemes in different environments, using multiple measures of phonological context.
Results
Both morphemes were found to exhibit notably contrastive marking patterns in some contexts. Each was most sensitive to a different combination of phonological influences in the verb stem and the following word.
Conclusions
These findings extend existing evidence from monolingual speakers for the influence of word-final phonological context on morpheme production to a bilingual population. Further, novel findings not yet attested in previous research support an expanded consideration of phonological context in clinical decision making and future research related to word-final morphology.from #Audiology via xlomafota13 on Inoreader http://ift.tt/2vNKpIW
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Electrophysiological Evidence for the Sources of the Masking Level Difference
Purpose
The purpose of this review article is to review evidence from auditory evoked potential studies to describe the contributions of the auditory brainstem and cortex to the generation of the masking level difference (MLD).
Method
A literature review was performed, focusing on the auditory brainstem, middle, and late latency responses used in protocols similar to those used to generate the behavioral MLD.
Results
Temporal coding of the signals necessary for generating the MLD occurs in the auditory periphery and brainstem. Brainstem disorders up to wave III of the auditory brainstem response (ABR) can disrupt the MLD. The full MLD requires input to the generators of the auditory late latency potentials to produce all characteristics of the MLD; these characteristics include threshold differences for various binaural signal and noise conditions. Studies using central auditory lesions are beginning to identify the cortical effects on the MLD.
Conclusions
The MLD requires auditory processing from the periphery to cortical areas. A healthy auditory periphery and brainstem codes temporal synchrony, which is essential for the ABR. Threshold differences require engaging cortical function beyond the primary auditory cortex. More studies using cortical lesions and evoked potentials or imaging should clarify the specific cortical areas involved in the MLD.from #Audiology via ola Kala on Inoreader http://ift.tt/2uD5Qhs
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Influences of Phonological Context on Tense Marking in Spanish–English Dual Language Learners
Purpose
The emergence of tense-morpheme marking during language acquisition is highly variable, which confounds the use of tense marking as a diagnostic indicator of language impairment in linguistically diverse populations. In this study, we seek to better understand tense-marking patterns in young bilingual children by comparing phonological influences on marking of 2 word-final tense morphemes.
Method
In spontaneous connected speech samples from 10 Spanish–English dual language learners aged 56–66 months (M = 61.7, SD = 3.4), we examined marking rates of past tense -ed and third person singular -s morphemes in different environments, using multiple measures of phonological context.
Results
Both morphemes were found to exhibit notably contrastive marking patterns in some contexts. Each was most sensitive to a different combination of phonological influences in the verb stem and the following word.
Conclusions
These findings extend existing evidence from monolingual speakers for the influence of word-final phonological context on morpheme production to a bilingual population. Further, novel findings not yet attested in previous research support an expanded consideration of phonological context in clinical decision making and future research related to word-final morphology.from #Audiology via ola Kala on Inoreader http://ift.tt/2vNKpIW
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Electrophysiological Evidence for the Sources of the Masking Level Difference
Purpose
The purpose of this review article is to review evidence from auditory evoked potential studies to describe the contributions of the auditory brainstem and cortex to the generation of the masking level difference (MLD).
Method
A literature review was performed, focusing on the auditory brainstem, middle, and late latency responses used in protocols similar to those used to generate the behavioral MLD.
Results
Temporal coding of the signals necessary for generating the MLD occurs in the auditory periphery and brainstem. Brainstem disorders up to wave III of the auditory brainstem response (ABR) can disrupt the MLD. The full MLD requires input to the generators of the auditory late latency potentials to produce all characteristics of the MLD; these characteristics include threshold differences for various binaural signal and noise conditions. Studies using central auditory lesions are beginning to identify the cortical effects on the MLD.
Conclusions
The MLD requires auditory processing from the periphery to cortical areas. A healthy auditory periphery and brainstem codes temporal synchrony, which is essential for the ABR. Threshold differences require engaging cortical function beyond the primary auditory cortex. More studies using cortical lesions and evoked potentials or imaging should clarify the specific cortical areas involved in the MLD.from #Audiology via ola Kala on Inoreader http://ift.tt/2uD5Qhs
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Influences of Phonological Context on Tense Marking in Spanish–English Dual Language Learners
Purpose
The emergence of tense-morpheme marking during language acquisition is highly variable, which confounds the use of tense marking as a diagnostic indicator of language impairment in linguistically diverse populations. In this study, we seek to better understand tense-marking patterns in young bilingual children by comparing phonological influences on marking of 2 word-final tense morphemes.
Method
In spontaneous connected speech samples from 10 Spanish–English dual language learners aged 56–66 months (M = 61.7, SD = 3.4), we examined marking rates of past tense -ed and third person singular -s morphemes in different environments, using multiple measures of phonological context.
Results
Both morphemes were found to exhibit notably contrastive marking patterns in some contexts. Each was most sensitive to a different combination of phonological influences in the verb stem and the following word.
Conclusions
These findings extend existing evidence from monolingual speakers for the influence of word-final phonological context on morpheme production to a bilingual population. Further, novel findings not yet attested in previous research support an expanded consideration of phonological context in clinical decision making and future research related to word-final morphology.from #Audiology via ola Kala on Inoreader http://ift.tt/2vNKpIW
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Otoliths - Accelerometer and seismometer; Implications in Vestibular Evoked Myogenic Potential (VEMP)
Publication date: Available online 27 July 2017
Source:Hearing Research
Author(s): Wally Grant, Ian Curthoys
Vestibular otolithic organs are recognized as transducers of head acceleration and they function as such up to their corner frequency or undamped natural frequency. It is well recognized that these organs respond to frequencies above their corner frequency up to the 2–3 kHz range (Curthoys et al., 2016). A mechanics model for the transduction of these organs is developed that predicts the response below the undamped natural frequency as an accelerometer and above that frequency as a seismometer. The model is converted to a transfer function using hair cell bundle deflection. Measured threshold acceleration stimuli are used along with threshold deflections for threshold transfer function values. These are compared to model predicted values, both below and above their undamped natural frequency. Threshold deflection values are adjusted to match the model transfer function. The resulting threshold deflection values were well within in measure threshold bundle deflections. Vestibular Evoked Myogenic Potentials (VEMP) today routinely uses stimulus frequencies of 500 and 1000 Hz, and otoliths have been established incontrovertibly by clinical and neural evidence as the stimulus source. The mechanism for stimulus at these frequencies above the undamped natural frequency of otoliths is presented where otoliths are utilizing a seismometer mode of response for VEMPS transduction.
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Source:Hearing Research
Author(s): Wally Grant, Ian Curthoys
Vestibular otolithic organs are recognized as transducers of head acceleration and they function as such up to their corner frequency or undamped natural frequency. It is well recognized that these organs respond to frequencies above their corner frequency up to the 2–3 kHz range (Curthoys et al., 2016). A mechanics model for the transduction of these organs is developed that predicts the response below the undamped natural frequency as an accelerometer and above that frequency as a seismometer. The model is converted to a transfer function using hair cell bundle deflection. Measured threshold acceleration stimuli are used along with threshold deflections for threshold transfer function values. These are compared to model predicted values, both below and above their undamped natural frequency. Threshold deflection values are adjusted to match the model transfer function. The resulting threshold deflection values were well within in measure threshold bundle deflections. Vestibular Evoked Myogenic Potentials (VEMP) today routinely uses stimulus frequencies of 500 and 1000 Hz, and otoliths have been established incontrovertibly by clinical and neural evidence as the stimulus source. The mechanism for stimulus at these frequencies above the undamped natural frequency of otoliths is presented where otoliths are utilizing a seismometer mode of response for VEMPS transduction.
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Changes of metabolism and functional connectivity in late-onset deafness: Evidence from cerebral 18F-FDG-PET
Publication date: Available online 27 July 2017
Source:Hearing Research
Author(s): Antoine Verger, Stephane Roman, Rose-May Chaudat, Olivier Felician, Mathieu Ceccaldi, Mira Didic, Eric Guedj
Hearing loss is known to impact brain function. The aim of this study was to characterize cerebral metabolic Positron Emission Tomography (PET) changes in elderly patients fulfilling criteria for cochlear implant and investigate the impact of hearing loss on functional connectivity. Statistical Parametric Mapping-T-scores-maps comparisons of 18F-FDG-PET of 27 elderly patients fulfilling criteria for cochlear implant for hearing loss (best-aided speech intelligibility lower or equal to 50%) and 27 matched healthy subjects (p < 0.005, corrected for volume extent) were performed. Metabolic connectivity was evaluated through interregional correlation analysis. Patients were found to have decreased metabolism within the right associative auditory cortex, while increased metabolism was found in prefrontal areas, pre- and post-central areas, the cingulum and the left inferior parietal gyrus. The right associative auditory cortex was integrated into a network of increased metabolic connectivity that included pre- and post-central areas, the cingulum, the right inferior parietal gyrus, as well as the striatum on both sides. Metabolic values of the right associative auditory cortex and left inferior parietal gyrus were positively correlated with performance on neuropsychological test scores. These findings provide further insight into the reorganization of the connectome through sensory loss and compensatory mechanisms in elderly patients with severe hearing loss.
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Source:Hearing Research
Author(s): Antoine Verger, Stephane Roman, Rose-May Chaudat, Olivier Felician, Mathieu Ceccaldi, Mira Didic, Eric Guedj
Hearing loss is known to impact brain function. The aim of this study was to characterize cerebral metabolic Positron Emission Tomography (PET) changes in elderly patients fulfilling criteria for cochlear implant and investigate the impact of hearing loss on functional connectivity. Statistical Parametric Mapping-T-scores-maps comparisons of 18F-FDG-PET of 27 elderly patients fulfilling criteria for cochlear implant for hearing loss (best-aided speech intelligibility lower or equal to 50%) and 27 matched healthy subjects (p < 0.005, corrected for volume extent) were performed. Metabolic connectivity was evaluated through interregional correlation analysis. Patients were found to have decreased metabolism within the right associative auditory cortex, while increased metabolism was found in prefrontal areas, pre- and post-central areas, the cingulum and the left inferior parietal gyrus. The right associative auditory cortex was integrated into a network of increased metabolic connectivity that included pre- and post-central areas, the cingulum, the right inferior parietal gyrus, as well as the striatum on both sides. Metabolic values of the right associative auditory cortex and left inferior parietal gyrus were positively correlated with performance on neuropsychological test scores. These findings provide further insight into the reorganization of the connectome through sensory loss and compensatory mechanisms in elderly patients with severe hearing loss.
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Detecting temporal changes in acoustic scenes: The variable benefit of selective attention
Publication date: Available online 27 July 2017
Source:Hearing Research
Author(s): Laurent Demany, Yann Bayle, Emilie Puginier, Catherine Semal
Four experiments investigated change detection in acoustic scenes consisting of a sum of five amplitude-modulated pure tones. As the tones were about 0.7 octave apart and were amplitude-modulated with different frequencies (in the range 2–32 Hz), they were perceived as separate streams. Listeners had to detect a change in the frequency (experiments 1 and 2) or the shape (experiments 3 and 4) of the modulation of one of the five tones, in the presence of an informative cue orienting selective attention either before the scene (pre-cue) or after it (post-cue). The changes left intensity unchanged and were not detectable in the spectral (tonotopic) domain. Performance was much better with pre-cues than with post-cues. Thus, change deafness was manifest in the absence of an appropriate focusing of attention when the change occurred, even though the streams and the changes to be detected were acoustically very simple (in contrast to the conditions used in previous demonstrations of change deafness). In one case, the results were consistent with a model based on the assumption that change detection was possible if and only if attention was endogenously focused on a single tone. However, it was also found that changes resulting in a steepening of amplitude rises were to some extent able to draw attention exogenously. Change detection was not markedly facilitated when the change produced a discontinuity in the modulation domain, contrary to what could be expected from the perspective of predictive coding.
from #Audiology via ola Kala on Inoreader http://ift.tt/2w34dYe
via IFTTT
Source:Hearing Research
Author(s): Laurent Demany, Yann Bayle, Emilie Puginier, Catherine Semal
Four experiments investigated change detection in acoustic scenes consisting of a sum of five amplitude-modulated pure tones. As the tones were about 0.7 octave apart and were amplitude-modulated with different frequencies (in the range 2–32 Hz), they were perceived as separate streams. Listeners had to detect a change in the frequency (experiments 1 and 2) or the shape (experiments 3 and 4) of the modulation of one of the five tones, in the presence of an informative cue orienting selective attention either before the scene (pre-cue) or after it (post-cue). The changes left intensity unchanged and were not detectable in the spectral (tonotopic) domain. Performance was much better with pre-cues than with post-cues. Thus, change deafness was manifest in the absence of an appropriate focusing of attention when the change occurred, even though the streams and the changes to be detected were acoustically very simple (in contrast to the conditions used in previous demonstrations of change deafness). In one case, the results were consistent with a model based on the assumption that change detection was possible if and only if attention was endogenously focused on a single tone. However, it was also found that changes resulting in a steepening of amplitude rises were to some extent able to draw attention exogenously. Change detection was not markedly facilitated when the change produced a discontinuity in the modulation domain, contrary to what could be expected from the perspective of predictive coding.
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In vivo recording of the vestibular microphonic in mammals
Publication date: Available online 26 July 2017
Source:Hearing Research
Author(s): C.J. Pastras, I.S. Curthoys, D.J. Brown
BackgroundThe Vestibular Microphonic (VM) has only featured in a handful of publications, mostly involving non-mammalian and ex vivo models. The VM is the extracellular analogue of the vestibular hair cell receptor current, and offers a tool to monitor vestibular hair cell activity in vivo.ObjectiveTo characterise features of the VM measured in vivo in guinea pigs, using a relatively simple experimental setup.MethodsThe VM, evoked by bone-conducted vibration (BCV), was recorded from the basal surface of either the utricular or saccular macula after surgical removal of the cochlea, in 27 guinea pigs.ResultsThe VM remained after vestibular nerve blockade, but was abolished following end-organ destruction or death. The VM reversed polarity as the recording electrode tracked across the utricular or saccular macula surface, or through the utricular macula. The VM could be evoked by BCV stimuli of frequencies between 100 Hz and 5 kHz, and was largest to vibrations between 600 Hz and 800 Hz. Experimental manipulations demonstrated a reduction in the VM amplitude with maculae displacement, or rupture of the utricular membrane.ConclusionsResults mirror those obtained in previous ex vivo studies, and further demonstrate that vestibular hair cells are sensitive to vibrations of several kilohertz. Changes in the VM with maculae displacement or rupture suggest utricular hydrops may alter vestibular hair cell sensitivity due to either mechanical or ionic changes.
from #Audiology via ola Kala on Inoreader http://ift.tt/2vb36cn
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Source:Hearing Research
Author(s): C.J. Pastras, I.S. Curthoys, D.J. Brown
BackgroundThe Vestibular Microphonic (VM) has only featured in a handful of publications, mostly involving non-mammalian and ex vivo models. The VM is the extracellular analogue of the vestibular hair cell receptor current, and offers a tool to monitor vestibular hair cell activity in vivo.ObjectiveTo characterise features of the VM measured in vivo in guinea pigs, using a relatively simple experimental setup.MethodsThe VM, evoked by bone-conducted vibration (BCV), was recorded from the basal surface of either the utricular or saccular macula after surgical removal of the cochlea, in 27 guinea pigs.ResultsThe VM remained after vestibular nerve blockade, but was abolished following end-organ destruction or death. The VM reversed polarity as the recording electrode tracked across the utricular or saccular macula surface, or through the utricular macula. The VM could be evoked by BCV stimuli of frequencies between 100 Hz and 5 kHz, and was largest to vibrations between 600 Hz and 800 Hz. Experimental manipulations demonstrated a reduction in the VM amplitude with maculae displacement, or rupture of the utricular membrane.ConclusionsResults mirror those obtained in previous ex vivo studies, and further demonstrate that vestibular hair cells are sensitive to vibrations of several kilohertz. Changes in the VM with maculae displacement or rupture suggest utricular hydrops may alter vestibular hair cell sensitivity due to either mechanical or ionic changes.
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Tympanic membrane pressure buffering function at quasi-static and low-frequency pressure variations
Publication date: Available online 26 July 2017
Source:Hearing Research
Author(s): Wasil H.M. Salih, Pieter G.G. Muyshondt, Joris J.J. Dirckx
Deformation of the tympanic membrane is known to contribute to the pressure regulation processes in the middle ear cleft. In this paper we investigated pressure variations in the rabbit middle ear in response to sinusoidal varying pressures applied to the ear canal, with frequencies ranging from 0.5 Hz to 50 Hz and pressure amplitudes ranging between 0.25 kPa and 1 kPa. The transtympanic pressure difference was found to be smallest in the quasi-static range, and quickly increased as a function of frequency. The response curves showed asymmetry, with larger transtympanic pressures when positive pressures were applied in the ear canal. Normalized transtympanic pressure amplitudes remained fairly constant as a function of input pressure, with values in the range of 60%–70% relative to the applied pressure. The total harmonic distortion of the middle ear pressure signal was calculated and was found to be very small (≤2%) for low-pressure amplitudes and low frequencies. For pressure amplitudes in the order of 0.25 kPa–0.5 kPa, it increased to about 10% at 50 Hz. When a 1 kPa pressure amplitude was applied, variation between animals became large and distortion values up to 30% at 50 Hz were observed. The results showed that pressure buffering due to tympanic membrane displacement was most effective for compensating small transtympanic pressure loads at low frequencies.
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Source:Hearing Research
Author(s): Wasil H.M. Salih, Pieter G.G. Muyshondt, Joris J.J. Dirckx
Deformation of the tympanic membrane is known to contribute to the pressure regulation processes in the middle ear cleft. In this paper we investigated pressure variations in the rabbit middle ear in response to sinusoidal varying pressures applied to the ear canal, with frequencies ranging from 0.5 Hz to 50 Hz and pressure amplitudes ranging between 0.25 kPa and 1 kPa. The transtympanic pressure difference was found to be smallest in the quasi-static range, and quickly increased as a function of frequency. The response curves showed asymmetry, with larger transtympanic pressures when positive pressures were applied in the ear canal. Normalized transtympanic pressure amplitudes remained fairly constant as a function of input pressure, with values in the range of 60%–70% relative to the applied pressure. The total harmonic distortion of the middle ear pressure signal was calculated and was found to be very small (≤2%) for low-pressure amplitudes and low frequencies. For pressure amplitudes in the order of 0.25 kPa–0.5 kPa, it increased to about 10% at 50 Hz. When a 1 kPa pressure amplitude was applied, variation between animals became large and distortion values up to 30% at 50 Hz were observed. The results showed that pressure buffering due to tympanic membrane displacement was most effective for compensating small transtympanic pressure loads at low frequencies.
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Otoliths - Accelerometer and seismometer; Implications in Vestibular Evoked Myogenic Potential (VEMP)
Publication date: Available online 27 July 2017
Source:Hearing Research
Author(s): Wally Grant, Ian Curthoys
Vestibular otolithic organs are recognized as transducers of head acceleration and they function as such up to their corner frequency or undamped natural frequency. It is well recognized that these organs respond to frequencies above their corner frequency up to the 2–3 kHz range (Curthoys et al., 2016). A mechanics model for the transduction of these organs is developed that predicts the response below the undamped natural frequency as an accelerometer and above that frequency as a seismometer. The model is converted to a transfer function using hair cell bundle deflection. Measured threshold acceleration stimuli are used along with threshold deflections for threshold transfer function values. These are compared to model predicted values, both below and above their undamped natural frequency. Threshold deflection values are adjusted to match the model transfer function. The resulting threshold deflection values were well within in measure threshold bundle deflections. Vestibular Evoked Myogenic Potentials (VEMP) today routinely uses stimulus frequencies of 500 and 1000 Hz, and otoliths have been established incontrovertibly by clinical and neural evidence as the stimulus source. The mechanism for stimulus at these frequencies above the undamped natural frequency of otoliths is presented where otoliths are utilizing a seismometer mode of response for VEMPS transduction.
from #Audiology via ola Kala on Inoreader http://ift.tt/2uBp1rQ
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Source:Hearing Research
Author(s): Wally Grant, Ian Curthoys
Vestibular otolithic organs are recognized as transducers of head acceleration and they function as such up to their corner frequency or undamped natural frequency. It is well recognized that these organs respond to frequencies above their corner frequency up to the 2–3 kHz range (Curthoys et al., 2016). A mechanics model for the transduction of these organs is developed that predicts the response below the undamped natural frequency as an accelerometer and above that frequency as a seismometer. The model is converted to a transfer function using hair cell bundle deflection. Measured threshold acceleration stimuli are used along with threshold deflections for threshold transfer function values. These are compared to model predicted values, both below and above their undamped natural frequency. Threshold deflection values are adjusted to match the model transfer function. The resulting threshold deflection values were well within in measure threshold bundle deflections. Vestibular Evoked Myogenic Potentials (VEMP) today routinely uses stimulus frequencies of 500 and 1000 Hz, and otoliths have been established incontrovertibly by clinical and neural evidence as the stimulus source. The mechanism for stimulus at these frequencies above the undamped natural frequency of otoliths is presented where otoliths are utilizing a seismometer mode of response for VEMPS transduction.
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Changes of metabolism and functional connectivity in late-onset deafness: Evidence from cerebral 18F-FDG-PET
Publication date: Available online 27 July 2017
Source:Hearing Research
Author(s): Antoine Verger, Stephane Roman, Rose-May Chaudat, Olivier Felician, Mathieu Ceccaldi, Mira Didic, Eric Guedj
Hearing loss is known to impact brain function. The aim of this study was to characterize cerebral metabolic Positron Emission Tomography (PET) changes in elderly patients fulfilling criteria for cochlear implant and investigate the impact of hearing loss on functional connectivity. Statistical Parametric Mapping-T-scores-maps comparisons of 18F-FDG-PET of 27 elderly patients fulfilling criteria for cochlear implant for hearing loss (best-aided speech intelligibility lower or equal to 50%) and 27 matched healthy subjects (p < 0.005, corrected for volume extent) were performed. Metabolic connectivity was evaluated through interregional correlation analysis. Patients were found to have decreased metabolism within the right associative auditory cortex, while increased metabolism was found in prefrontal areas, pre- and post-central areas, the cingulum and the left inferior parietal gyrus. The right associative auditory cortex was integrated into a network of increased metabolic connectivity that included pre- and post-central areas, the cingulum, the right inferior parietal gyrus, as well as the striatum on both sides. Metabolic values of the right associative auditory cortex and left inferior parietal gyrus were positively correlated with performance on neuropsychological test scores. These findings provide further insight into the reorganization of the connectome through sensory loss and compensatory mechanisms in elderly patients with severe hearing loss.
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Source:Hearing Research
Author(s): Antoine Verger, Stephane Roman, Rose-May Chaudat, Olivier Felician, Mathieu Ceccaldi, Mira Didic, Eric Guedj
Hearing loss is known to impact brain function. The aim of this study was to characterize cerebral metabolic Positron Emission Tomography (PET) changes in elderly patients fulfilling criteria for cochlear implant and investigate the impact of hearing loss on functional connectivity. Statistical Parametric Mapping-T-scores-maps comparisons of 18F-FDG-PET of 27 elderly patients fulfilling criteria for cochlear implant for hearing loss (best-aided speech intelligibility lower or equal to 50%) and 27 matched healthy subjects (p < 0.005, corrected for volume extent) were performed. Metabolic connectivity was evaluated through interregional correlation analysis. Patients were found to have decreased metabolism within the right associative auditory cortex, while increased metabolism was found in prefrontal areas, pre- and post-central areas, the cingulum and the left inferior parietal gyrus. The right associative auditory cortex was integrated into a network of increased metabolic connectivity that included pre- and post-central areas, the cingulum, the right inferior parietal gyrus, as well as the striatum on both sides. Metabolic values of the right associative auditory cortex and left inferior parietal gyrus were positively correlated with performance on neuropsychological test scores. These findings provide further insight into the reorganization of the connectome through sensory loss and compensatory mechanisms in elderly patients with severe hearing loss.
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Detecting temporal changes in acoustic scenes: The variable benefit of selective attention
Publication date: Available online 27 July 2017
Source:Hearing Research
Author(s): Laurent Demany, Yann Bayle, Emilie Puginier, Catherine Semal
Four experiments investigated change detection in acoustic scenes consisting of a sum of five amplitude-modulated pure tones. As the tones were about 0.7 octave apart and were amplitude-modulated with different frequencies (in the range 2–32 Hz), they were perceived as separate streams. Listeners had to detect a change in the frequency (experiments 1 and 2) or the shape (experiments 3 and 4) of the modulation of one of the five tones, in the presence of an informative cue orienting selective attention either before the scene (pre-cue) or after it (post-cue). The changes left intensity unchanged and were not detectable in the spectral (tonotopic) domain. Performance was much better with pre-cues than with post-cues. Thus, change deafness was manifest in the absence of an appropriate focusing of attention when the change occurred, even though the streams and the changes to be detected were acoustically very simple (in contrast to the conditions used in previous demonstrations of change deafness). In one case, the results were consistent with a model based on the assumption that change detection was possible if and only if attention was endogenously focused on a single tone. However, it was also found that changes resulting in a steepening of amplitude rises were to some extent able to draw attention exogenously. Change detection was not markedly facilitated when the change produced a discontinuity in the modulation domain, contrary to what could be expected from the perspective of predictive coding.
from #Audiology via ola Kala on Inoreader http://ift.tt/2w34dYe
via IFTTT
Source:Hearing Research
Author(s): Laurent Demany, Yann Bayle, Emilie Puginier, Catherine Semal
Four experiments investigated change detection in acoustic scenes consisting of a sum of five amplitude-modulated pure tones. As the tones were about 0.7 octave apart and were amplitude-modulated with different frequencies (in the range 2–32 Hz), they were perceived as separate streams. Listeners had to detect a change in the frequency (experiments 1 and 2) or the shape (experiments 3 and 4) of the modulation of one of the five tones, in the presence of an informative cue orienting selective attention either before the scene (pre-cue) or after it (post-cue). The changes left intensity unchanged and were not detectable in the spectral (tonotopic) domain. Performance was much better with pre-cues than with post-cues. Thus, change deafness was manifest in the absence of an appropriate focusing of attention when the change occurred, even though the streams and the changes to be detected were acoustically very simple (in contrast to the conditions used in previous demonstrations of change deafness). In one case, the results were consistent with a model based on the assumption that change detection was possible if and only if attention was endogenously focused on a single tone. However, it was also found that changes resulting in a steepening of amplitude rises were to some extent able to draw attention exogenously. Change detection was not markedly facilitated when the change produced a discontinuity in the modulation domain, contrary to what could be expected from the perspective of predictive coding.
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In vivo recording of the vestibular microphonic in mammals
Publication date: Available online 26 July 2017
Source:Hearing Research
Author(s): C.J. Pastras, I.S. Curthoys, D.J. Brown
BackgroundThe Vestibular Microphonic (VM) has only featured in a handful of publications, mostly involving non-mammalian and ex vivo models. The VM is the extracellular analogue of the vestibular hair cell receptor current, and offers a tool to monitor vestibular hair cell activity in vivo.ObjectiveTo characterise features of the VM measured in vivo in guinea pigs, using a relatively simple experimental setup.MethodsThe VM, evoked by bone-conducted vibration (BCV), was recorded from the basal surface of either the utricular or saccular macula after surgical removal of the cochlea, in 27 guinea pigs.ResultsThe VM remained after vestibular nerve blockade, but was abolished following end-organ destruction or death. The VM reversed polarity as the recording electrode tracked across the utricular or saccular macula surface, or through the utricular macula. The VM could be evoked by BCV stimuli of frequencies between 100 Hz and 5 kHz, and was largest to vibrations between 600 Hz and 800 Hz. Experimental manipulations demonstrated a reduction in the VM amplitude with maculae displacement, or rupture of the utricular membrane.ConclusionsResults mirror those obtained in previous ex vivo studies, and further demonstrate that vestibular hair cells are sensitive to vibrations of several kilohertz. Changes in the VM with maculae displacement or rupture suggest utricular hydrops may alter vestibular hair cell sensitivity due to either mechanical or ionic changes.
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Source:Hearing Research
Author(s): C.J. Pastras, I.S. Curthoys, D.J. Brown
BackgroundThe Vestibular Microphonic (VM) has only featured in a handful of publications, mostly involving non-mammalian and ex vivo models. The VM is the extracellular analogue of the vestibular hair cell receptor current, and offers a tool to monitor vestibular hair cell activity in vivo.ObjectiveTo characterise features of the VM measured in vivo in guinea pigs, using a relatively simple experimental setup.MethodsThe VM, evoked by bone-conducted vibration (BCV), was recorded from the basal surface of either the utricular or saccular macula after surgical removal of the cochlea, in 27 guinea pigs.ResultsThe VM remained after vestibular nerve blockade, but was abolished following end-organ destruction or death. The VM reversed polarity as the recording electrode tracked across the utricular or saccular macula surface, or through the utricular macula. The VM could be evoked by BCV stimuli of frequencies between 100 Hz and 5 kHz, and was largest to vibrations between 600 Hz and 800 Hz. Experimental manipulations demonstrated a reduction in the VM amplitude with maculae displacement, or rupture of the utricular membrane.ConclusionsResults mirror those obtained in previous ex vivo studies, and further demonstrate that vestibular hair cells are sensitive to vibrations of several kilohertz. Changes in the VM with maculae displacement or rupture suggest utricular hydrops may alter vestibular hair cell sensitivity due to either mechanical or ionic changes.
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Tympanic membrane pressure buffering function at quasi-static and low-frequency pressure variations
Publication date: Available online 26 July 2017
Source:Hearing Research
Author(s): Wasil H.M. Salih, Pieter G.G. Muyshondt, Joris J.J. Dirckx
Deformation of the tympanic membrane is known to contribute to the pressure regulation processes in the middle ear cleft. In this paper we investigated pressure variations in the rabbit middle ear in response to sinusoidal varying pressures applied to the ear canal, with frequencies ranging from 0.5 Hz to 50 Hz and pressure amplitudes ranging between 0.25 kPa and 1 kPa. The transtympanic pressure difference was found to be smallest in the quasi-static range, and quickly increased as a function of frequency. The response curves showed asymmetry, with larger transtympanic pressures when positive pressures were applied in the ear canal. Normalized transtympanic pressure amplitudes remained fairly constant as a function of input pressure, with values in the range of 60%–70% relative to the applied pressure. The total harmonic distortion of the middle ear pressure signal was calculated and was found to be very small (≤2%) for low-pressure amplitudes and low frequencies. For pressure amplitudes in the order of 0.25 kPa–0.5 kPa, it increased to about 10% at 50 Hz. When a 1 kPa pressure amplitude was applied, variation between animals became large and distortion values up to 30% at 50 Hz were observed. The results showed that pressure buffering due to tympanic membrane displacement was most effective for compensating small transtympanic pressure loads at low frequencies.
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Source:Hearing Research
Author(s): Wasil H.M. Salih, Pieter G.G. Muyshondt, Joris J.J. Dirckx
Deformation of the tympanic membrane is known to contribute to the pressure regulation processes in the middle ear cleft. In this paper we investigated pressure variations in the rabbit middle ear in response to sinusoidal varying pressures applied to the ear canal, with frequencies ranging from 0.5 Hz to 50 Hz and pressure amplitudes ranging between 0.25 kPa and 1 kPa. The transtympanic pressure difference was found to be smallest in the quasi-static range, and quickly increased as a function of frequency. The response curves showed asymmetry, with larger transtympanic pressures when positive pressures were applied in the ear canal. Normalized transtympanic pressure amplitudes remained fairly constant as a function of input pressure, with values in the range of 60%–70% relative to the applied pressure. The total harmonic distortion of the middle ear pressure signal was calculated and was found to be very small (≤2%) for low-pressure amplitudes and low frequencies. For pressure amplitudes in the order of 0.25 kPa–0.5 kPa, it increased to about 10% at 50 Hz. When a 1 kPa pressure amplitude was applied, variation between animals became large and distortion values up to 30% at 50 Hz were observed. The results showed that pressure buffering due to tympanic membrane displacement was most effective for compensating small transtympanic pressure loads at low frequencies.
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Otoliths - Accelerometer and seismometer; Implications in Vestibular Evoked Myogenic Potential (VEMP)
Source:Hearing Research
Author(s): Wally Grant, Ian Curthoys
Vestibular otolithic organs are recognized as transducers of head acceleration and they function as such up to their corner frequency or undamped natural frequency. It is well recognized that these organs respond to frequencies above their corner frequency up to the 2–3 kHz range (Curthoys et al., 2016). A mechanics model for the transduction of these organs is developed that predicts the response below the undamped natural frequency as an accelerometer and above that frequency as a seismometer. The model is converted to a transfer function using hair cell bundle deflection. Measured threshold acceleration stimuli are used along with threshold deflections for threshold transfer function values. These are compared to model predicted values, both below and above their undamped natural frequency. Threshold deflection values are adjusted to match the model transfer function. The resulting threshold deflection values were well within in measure threshold bundle deflections. Vestibular Evoked Myogenic Potentials (VEMP) today routinely uses stimulus frequencies of 500 and 1000 Hz, and otoliths have been established incontrovertibly by clinical and neural evidence as the stimulus source. The mechanism for stimulus at these frequencies above the undamped natural frequency of otoliths is presented where otoliths are utilizing a seismometer mode of response for VEMPS transduction.
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Changes of metabolism and functional connectivity in late-onset deafness: Evidence from cerebral 18F-FDG-PET
Source:Hearing Research
Author(s): Antoine Verger, Stephane Roman, Rose-May Chaudat, Olivier Felician, Mathieu Ceccaldi, Mira Didic, Eric Guedj
Hearing loss is known to impact brain function. The aim of this study was to characterize cerebral metabolic Positron Emission Tomography (PET) changes in elderly patients fulfilling criteria for cochlear implant and investigate the impact of hearing loss on functional connectivity. Statistical Parametric Mapping-T-scores-maps comparisons of 18F-FDG-PET of 27 elderly patients fulfilling criteria for cochlear implant for hearing loss (best-aided speech intelligibility lower or equal to 50%) and 27 matched healthy subjects (p < 0.005, corrected for volume extent) were performed. Metabolic connectivity was evaluated through interregional correlation analysis. Patients were found to have decreased metabolism within the right associative auditory cortex, while increased metabolism was found in prefrontal areas, pre- and post-central areas, the cingulum and the left inferior parietal gyrus. The right associative auditory cortex was integrated into a network of increased metabolic connectivity that included pre- and post-central areas, the cingulum, the right inferior parietal gyrus, as well as the striatum on both sides. Metabolic values of the right associative auditory cortex and left inferior parietal gyrus were positively correlated with performance on neuropsychological test scores. These findings provide further insight into the reorganization of the connectome through sensory loss and compensatory mechanisms in elderly patients with severe hearing loss.
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Detecting temporal changes in acoustic scenes: The variable benefit of selective attention
Source:Hearing Research
Author(s): Laurent Demany, Yann Bayle, Emilie Puginier, Catherine Semal
Four experiments investigated change detection in acoustic scenes consisting of a sum of five amplitude-modulated pure tones. As the tones were about 0.7 octave apart and were amplitude-modulated with different frequencies (in the range 2–32 Hz), they were perceived as separate streams. Listeners had to detect a change in the frequency (experiments 1 and 2) or the shape (experiments 3 and 4) of the modulation of one of the five tones, in the presence of an informative cue orienting selective attention either before the scene (pre-cue) or after it (post-cue). The changes left intensity unchanged and were not detectable in the spectral (tonotopic) domain. Performance was much better with pre-cues than with post-cues. Thus, change deafness was manifest in the absence of an appropriate focusing of attention when the change occurred, even though the streams and the changes to be detected were acoustically very simple (in contrast to the conditions used in previous demonstrations of change deafness). In one case, the results were consistent with a model based on the assumption that change detection was possible if and only if attention was endogenously focused on a single tone. However, it was also found that changes resulting in a steepening of amplitude rises were to some extent able to draw attention exogenously. Change detection was not markedly facilitated when the change produced a discontinuity in the modulation domain, contrary to what could be expected from the perspective of predictive coding.
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In vivo recording of the vestibular microphonic in mammals
Source:Hearing Research
Author(s): C.J. Pastras, I.S. Curthoys, D.J. Brown
BackgroundThe Vestibular Microphonic (VM) has only featured in a handful of publications, mostly involving non-mammalian and ex vivo models. The VM is the extracellular analogue of the vestibular hair cell receptor current, and offers a tool to monitor vestibular hair cell activity in vivo.ObjectiveTo characterise features of the VM measured in vivo in guinea pigs, using a relatively simple experimental setup.MethodsThe VM, evoked by bone-conducted vibration (BCV), was recorded from the basal surface of either the utricular or saccular macula after surgical removal of the cochlea, in 27 guinea pigs.ResultsThe VM remained after vestibular nerve blockade, but was abolished following end-organ destruction or death. The VM reversed polarity as the recording electrode tracked across the utricular or saccular macula surface, or through the utricular macula. The VM could be evoked by BCV stimuli of frequencies between 100 Hz and 5 kHz, and was largest to vibrations between 600 Hz and 800 Hz. Experimental manipulations demonstrated a reduction in the VM amplitude with maculae displacement, or rupture of the utricular membrane.ConclusionsResults mirror those obtained in previous ex vivo studies, and further demonstrate that vestibular hair cells are sensitive to vibrations of several kilohertz. Changes in the VM with maculae displacement or rupture suggest utricular hydrops may alter vestibular hair cell sensitivity due to either mechanical or ionic changes.
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Tympanic membrane pressure buffering function at quasi-static and low-frequency pressure variations
Source:Hearing Research
Author(s): Wasil H.M. Salih, Pieter G.G. Muyshondt, Joris J.J. Dirckx
Deformation of the tympanic membrane is known to contribute to the pressure regulation processes in the middle ear cleft. In this paper we investigated pressure variations in the rabbit middle ear in response to sinusoidal varying pressures applied to the ear canal, with frequencies ranging from 0.5 Hz to 50 Hz and pressure amplitudes ranging between 0.25 kPa and 1 kPa. The transtympanic pressure difference was found to be smallest in the quasi-static range, and quickly increased as a function of frequency. The response curves showed asymmetry, with larger transtympanic pressures when positive pressures were applied in the ear canal. Normalized transtympanic pressure amplitudes remained fairly constant as a function of input pressure, with values in the range of 60%–70% relative to the applied pressure. The total harmonic distortion of the middle ear pressure signal was calculated and was found to be very small (≤2%) for low-pressure amplitudes and low frequencies. For pressure amplitudes in the order of 0.25 kPa–0.5 kPa, it increased to about 10% at 50 Hz. When a 1 kPa pressure amplitude was applied, variation between animals became large and distortion values up to 30% at 50 Hz were observed. The results showed that pressure buffering due to tympanic membrane displacement was most effective for compensating small transtympanic pressure loads at low frequencies.
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Otoliths - Accelerometer and seismometer; Implications in Vestibular Evoked Myogenic Potential (VEMP)
Source:Hearing Research
Author(s): Wally Grant, Ian Curthoys
Vestibular otolithic organs are recognized as transducers of head acceleration and they function as such up to their corner frequency or undamped natural frequency. It is well recognized that these organs respond to frequencies above their corner frequency up to the 2–3 kHz range (Curthoys et al., 2016). A mechanics model for the transduction of these organs is developed that predicts the response below the undamped natural frequency as an accelerometer and above that frequency as a seismometer. The model is converted to a transfer function using hair cell bundle deflection. Measured threshold acceleration stimuli are used along with threshold deflections for threshold transfer function values. These are compared to model predicted values, both below and above their undamped natural frequency. Threshold deflection values are adjusted to match the model transfer function. The resulting threshold deflection values were well within in measure threshold bundle deflections. Vestibular Evoked Myogenic Potentials (VEMP) today routinely uses stimulus frequencies of 500 and 1000 Hz, and otoliths have been established incontrovertibly by clinical and neural evidence as the stimulus source. The mechanism for stimulus at these frequencies above the undamped natural frequency of otoliths is presented where otoliths are utilizing a seismometer mode of response for VEMPS transduction.
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Changes of metabolism and functional connectivity in late-onset deafness: Evidence from cerebral 18F-FDG-PET
Source:Hearing Research
Author(s): Antoine Verger, Stephane Roman, Rose-May Chaudat, Olivier Felician, Mathieu Ceccaldi, Mira Didic, Eric Guedj
Hearing loss is known to impact brain function. The aim of this study was to characterize cerebral metabolic Positron Emission Tomography (PET) changes in elderly patients fulfilling criteria for cochlear implant and investigate the impact of hearing loss on functional connectivity. Statistical Parametric Mapping-T-scores-maps comparisons of 18F-FDG-PET of 27 elderly patients fulfilling criteria for cochlear implant for hearing loss (best-aided speech intelligibility lower or equal to 50%) and 27 matched healthy subjects (p < 0.005, corrected for volume extent) were performed. Metabolic connectivity was evaluated through interregional correlation analysis. Patients were found to have decreased metabolism within the right associative auditory cortex, while increased metabolism was found in prefrontal areas, pre- and post-central areas, the cingulum and the left inferior parietal gyrus. The right associative auditory cortex was integrated into a network of increased metabolic connectivity that included pre- and post-central areas, the cingulum, the right inferior parietal gyrus, as well as the striatum on both sides. Metabolic values of the right associative auditory cortex and left inferior parietal gyrus were positively correlated with performance on neuropsychological test scores. These findings provide further insight into the reorganization of the connectome through sensory loss and compensatory mechanisms in elderly patients with severe hearing loss.
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Detecting temporal changes in acoustic scenes: The variable benefit of selective attention
Source:Hearing Research
Author(s): Laurent Demany, Yann Bayle, Emilie Puginier, Catherine Semal
Four experiments investigated change detection in acoustic scenes consisting of a sum of five amplitude-modulated pure tones. As the tones were about 0.7 octave apart and were amplitude-modulated with different frequencies (in the range 2–32 Hz), they were perceived as separate streams. Listeners had to detect a change in the frequency (experiments 1 and 2) or the shape (experiments 3 and 4) of the modulation of one of the five tones, in the presence of an informative cue orienting selective attention either before the scene (pre-cue) or after it (post-cue). The changes left intensity unchanged and were not detectable in the spectral (tonotopic) domain. Performance was much better with pre-cues than with post-cues. Thus, change deafness was manifest in the absence of an appropriate focusing of attention when the change occurred, even though the streams and the changes to be detected were acoustically very simple (in contrast to the conditions used in previous demonstrations of change deafness). In one case, the results were consistent with a model based on the assumption that change detection was possible if and only if attention was endogenously focused on a single tone. However, it was also found that changes resulting in a steepening of amplitude rises were to some extent able to draw attention exogenously. Change detection was not markedly facilitated when the change produced a discontinuity in the modulation domain, contrary to what could be expected from the perspective of predictive coding.
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In vivo recording of the vestibular microphonic in mammals
Source:Hearing Research
Author(s): C.J. Pastras, I.S. Curthoys, D.J. Brown
BackgroundThe Vestibular Microphonic (VM) has only featured in a handful of publications, mostly involving non-mammalian and ex vivo models. The VM is the extracellular analogue of the vestibular hair cell receptor current, and offers a tool to monitor vestibular hair cell activity in vivo.ObjectiveTo characterise features of the VM measured in vivo in guinea pigs, using a relatively simple experimental setup.MethodsThe VM, evoked by bone-conducted vibration (BCV), was recorded from the basal surface of either the utricular or saccular macula after surgical removal of the cochlea, in 27 guinea pigs.ResultsThe VM remained after vestibular nerve blockade, but was abolished following end-organ destruction or death. The VM reversed polarity as the recording electrode tracked across the utricular or saccular macula surface, or through the utricular macula. The VM could be evoked by BCV stimuli of frequencies between 100 Hz and 5 kHz, and was largest to vibrations between 600 Hz and 800 Hz. Experimental manipulations demonstrated a reduction in the VM amplitude with maculae displacement, or rupture of the utricular membrane.ConclusionsResults mirror those obtained in previous ex vivo studies, and further demonstrate that vestibular hair cells are sensitive to vibrations of several kilohertz. Changes in the VM with maculae displacement or rupture suggest utricular hydrops may alter vestibular hair cell sensitivity due to either mechanical or ionic changes.
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via IFTTT
Tympanic membrane pressure buffering function at quasi-static and low-frequency pressure variations
Source:Hearing Research
Author(s): Wasil H.M. Salih, Pieter G.G. Muyshondt, Joris J.J. Dirckx
Deformation of the tympanic membrane is known to contribute to the pressure regulation processes in the middle ear cleft. In this paper we investigated pressure variations in the rabbit middle ear in response to sinusoidal varying pressures applied to the ear canal, with frequencies ranging from 0.5 Hz to 50 Hz and pressure amplitudes ranging between 0.25 kPa and 1 kPa. The transtympanic pressure difference was found to be smallest in the quasi-static range, and quickly increased as a function of frequency. The response curves showed asymmetry, with larger transtympanic pressures when positive pressures were applied in the ear canal. Normalized transtympanic pressure amplitudes remained fairly constant as a function of input pressure, with values in the range of 60%–70% relative to the applied pressure. The total harmonic distortion of the middle ear pressure signal was calculated and was found to be very small (≤2%) for low-pressure amplitudes and low frequencies. For pressure amplitudes in the order of 0.25 kPa–0.5 kPa, it increased to about 10% at 50 Hz. When a 1 kPa pressure amplitude was applied, variation between animals became large and distortion values up to 30% at 50 Hz were observed. The results showed that pressure buffering due to tympanic membrane displacement was most effective for compensating small transtympanic pressure loads at low frequencies.
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Otoliths - Accelerometer and seismometer; Implications in Vestibular Evoked Myogenic Potential (VEMP)
Source:Hearing Research
Author(s): Wally Grant, Ian Curthoys
Vestibular otolithic organs are recognized as transducers of head acceleration and they function as such up to their corner frequency or undamped natural frequency. It is well recognized that these organs respond to frequencies above their corner frequency up to the 2–3 kHz range (Curthoys et al., 2016). A mechanics model for the transduction of these organs is developed that predicts the response below the undamped natural frequency as an accelerometer and above that frequency as a seismometer. The model is converted to a transfer function using hair cell bundle deflection. Measured threshold acceleration stimuli are used along with threshold deflections for threshold transfer function values. These are compared to model predicted values, both below and above their undamped natural frequency. Threshold deflection values are adjusted to match the model transfer function. The resulting threshold deflection values were well within in measure threshold bundle deflections. Vestibular Evoked Myogenic Potentials (VEMP) today routinely uses stimulus frequencies of 500 and 1000 Hz, and otoliths have been established incontrovertibly by clinical and neural evidence as the stimulus source. The mechanism for stimulus at these frequencies above the undamped natural frequency of otoliths is presented where otoliths are utilizing a seismometer mode of response for VEMPS transduction.
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Changes of metabolism and functional connectivity in late-onset deafness: Evidence from cerebral 18F-FDG-PET
Source:Hearing Research
Author(s): Antoine Verger, Stephane Roman, Rose-May Chaudat, Olivier Felician, Mathieu Ceccaldi, Mira Didic, Eric Guedj
Hearing loss is known to impact brain function. The aim of this study was to characterize cerebral metabolic Positron Emission Tomography (PET) changes in elderly patients fulfilling criteria for cochlear implant and investigate the impact of hearing loss on functional connectivity. Statistical Parametric Mapping-T-scores-maps comparisons of 18F-FDG-PET of 27 elderly patients fulfilling criteria for cochlear implant for hearing loss (best-aided speech intelligibility lower or equal to 50%) and 27 matched healthy subjects (p < 0.005, corrected for volume extent) were performed. Metabolic connectivity was evaluated through interregional correlation analysis. Patients were found to have decreased metabolism within the right associative auditory cortex, while increased metabolism was found in prefrontal areas, pre- and post-central areas, the cingulum and the left inferior parietal gyrus. The right associative auditory cortex was integrated into a network of increased metabolic connectivity that included pre- and post-central areas, the cingulum, the right inferior parietal gyrus, as well as the striatum on both sides. Metabolic values of the right associative auditory cortex and left inferior parietal gyrus were positively correlated with performance on neuropsychological test scores. These findings provide further insight into the reorganization of the connectome through sensory loss and compensatory mechanisms in elderly patients with severe hearing loss.
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Detecting temporal changes in acoustic scenes: The variable benefit of selective attention
Publication date: Available online 27 July 2017
Source:Hearing Research
Author(s): Laurent Demany, Yann Bayle, Emilie Puginier, Catherine Semal
Four experiments investigated change detection in acoustic scenes consisting of a sum of five amplitude-modulated pure tones. As the tones were about 0.7 octave apart and were amplitude-modulated with different frequencies (in the range 2–32 Hz), they were perceived as separate streams. Listeners had to detect a change in the frequency (experiments 1 and 2) or the shape (experiments 3 and 4) of the modulation of one of the five tones, in the presence of an informative cue orienting selective attention either before the scene (pre-cue) or after it (post-cue). The changes left intensity unchanged and were not detectable in the spectral (tonotopic) domain. Performance was much better with pre-cues than with post-cues. Thus, change deafness was manifest in the absence of an appropriate focusing of attention when the change occurred, even though the streams and the changes to be detected were acoustically very simple (in contrast to the conditions used in previous demonstrations of change deafness). In one case, the results were consistent with a model based on the assumption that change detection was possible if and only if attention was endogenously focused on a single tone. However, it was also found that changes resulting in a steepening of amplitude rises were to some extent able to draw attention exogenously. Change detection was not markedly facilitated when the change produced a discontinuity in the modulation domain, contrary to what could be expected from the perspective of predictive coding.
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via IFTTT
Source:Hearing Research
Author(s): Laurent Demany, Yann Bayle, Emilie Puginier, Catherine Semal
Four experiments investigated change detection in acoustic scenes consisting of a sum of five amplitude-modulated pure tones. As the tones were about 0.7 octave apart and were amplitude-modulated with different frequencies (in the range 2–32 Hz), they were perceived as separate streams. Listeners had to detect a change in the frequency (experiments 1 and 2) or the shape (experiments 3 and 4) of the modulation of one of the five tones, in the presence of an informative cue orienting selective attention either before the scene (pre-cue) or after it (post-cue). The changes left intensity unchanged and were not detectable in the spectral (tonotopic) domain. Performance was much better with pre-cues than with post-cues. Thus, change deafness was manifest in the absence of an appropriate focusing of attention when the change occurred, even though the streams and the changes to be detected were acoustically very simple (in contrast to the conditions used in previous demonstrations of change deafness). In one case, the results were consistent with a model based on the assumption that change detection was possible if and only if attention was endogenously focused on a single tone. However, it was also found that changes resulting in a steepening of amplitude rises were to some extent able to draw attention exogenously. Change detection was not markedly facilitated when the change produced a discontinuity in the modulation domain, contrary to what could be expected from the perspective of predictive coding.
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via IFTTT
In vivo recording of the vestibular microphonic in mammals
Source:Hearing Research
Author(s): C.J. Pastras, I.S. Curthoys, D.J. Brown
BackgroundThe Vestibular Microphonic (VM) has only featured in a handful of publications, mostly involving non-mammalian and ex vivo models. The VM is the extracellular analogue of the vestibular hair cell receptor current, and offers a tool to monitor vestibular hair cell activity in vivo.ObjectiveTo characterise features of the VM measured in vivo in guinea pigs, using a relatively simple experimental setup.MethodsThe VM, evoked by bone-conducted vibration (BCV), was recorded from the basal surface of either the utricular or saccular macula after surgical removal of the cochlea, in 27 guinea pigs.ResultsThe VM remained after vestibular nerve blockade, but was abolished following end-organ destruction or death. The VM reversed polarity as the recording electrode tracked across the utricular or saccular macula surface, or through the utricular macula. The VM could be evoked by BCV stimuli of frequencies between 100 Hz and 5 kHz, and was largest to vibrations between 600 Hz and 800 Hz. Experimental manipulations demonstrated a reduction in the VM amplitude with maculae displacement, or rupture of the utricular membrane.ConclusionsResults mirror those obtained in previous ex vivo studies, and further demonstrate that vestibular hair cells are sensitive to vibrations of several kilohertz. Changes in the VM with maculae displacement or rupture suggest utricular hydrops may alter vestibular hair cell sensitivity due to either mechanical or ionic changes.
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Tympanic membrane pressure buffering function at quasi-static and low-frequency pressure variations
Source:Hearing Research
Author(s): Wasil H.M. Salih, Pieter G.G. Muyshondt, Joris J.J. Dirckx
Deformation of the tympanic membrane is known to contribute to the pressure regulation processes in the middle ear cleft. In this paper we investigated pressure variations in the rabbit middle ear in response to sinusoidal varying pressures applied to the ear canal, with frequencies ranging from 0.5 Hz to 50 Hz and pressure amplitudes ranging between 0.25 kPa and 1 kPa. The transtympanic pressure difference was found to be smallest in the quasi-static range, and quickly increased as a function of frequency. The response curves showed asymmetry, with larger transtympanic pressures when positive pressures were applied in the ear canal. Normalized transtympanic pressure amplitudes remained fairly constant as a function of input pressure, with values in the range of 60%–70% relative to the applied pressure. The total harmonic distortion of the middle ear pressure signal was calculated and was found to be very small (≤2%) for low-pressure amplitudes and low frequencies. For pressure amplitudes in the order of 0.25 kPa–0.5 kPa, it increased to about 10% at 50 Hz. When a 1 kPa pressure amplitude was applied, variation between animals became large and distortion values up to 30% at 50 Hz were observed. The results showed that pressure buffering due to tympanic membrane displacement was most effective for compensating small transtympanic pressure loads at low frequencies.
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Synchronised vestibular signals increase the P300 event-related potential elicited by auditory oddballs.
 |
Related Articles |
Synchronised vestibular signals increase the P300 event-related potential elicited by auditory oddballs.
Brain Res. 2016 Oct 01;1648(Pt A):224-31
Authors: Schmidt-Kassow M, Wilkinson D, Denby E, Ferguson H
Abstract
The perception of beat within an auditory rhythm can be facilitated when accompanied by synchronised movements. Electrophysiological investigation shows that this facilitatory effect is associated with a larger P300 amplitude. It has remained unclear, however, which movement-related processes drive this P300 effect. To investigate whether vestibular signals play a role, we administered alternating, sub-sensory (mean=.3mA) galvanic current to the vestibular nerves of participants while they counted the number of oddballs presented in a stream of tones played at a rate of 1Hz. Consistent with a vestibular effect, the P300 elicited by the oddballs was increased during stimulation relative to a sham condition, but only when the frequency of the alternating current matched that at which the tones were played. This finding supports the general idea that the vestibular system is involved in audio-motor synchronisation and is the first to show by electrophysiological means that it influences cognitive processes involved in beat perception.
PMID: 27423517 [PubMed - indexed for MEDLINE]
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Synchronised vestibular signals increase the P300 event-related potential elicited by auditory oddballs.
|
Related Articles |
Synchronised vestibular signals increase the P300 event-related potential elicited by auditory oddballs.
Brain Res. 2016 Oct 01;1648(Pt A):224-31
Authors: Schmidt-Kassow M, Wilkinson D, Denby E, Ferguson H
Abstract
The perception of beat within an auditory rhythm can be facilitated when accompanied by synchronised movements. Electrophysiological investigation shows that this facilitatory effect is associated with a larger P300 amplitude. It has remained unclear, however, which movement-related processes drive this P300 effect. To investigate whether vestibular signals play a role, we administered alternating, sub-sensory (mean=.3mA) galvanic current to the vestibular nerves of participants while they counted the number of oddballs presented in a stream of tones played at a rate of 1Hz. Consistent with a vestibular effect, the P300 elicited by the oddballs was increased during stimulation relative to a sham condition, but only when the frequency of the alternating current matched that at which the tones were played. This finding supports the general idea that the vestibular system is involved in audio-motor synchronisation and is the first to show by electrophysiological means that it influences cognitive processes involved in beat perception.
PMID: 27423517 [PubMed - indexed for MEDLINE]
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Symbolic Play and Novel Noun Learning in Deaf and Hearing Children: Longitudinal Effects of Access to Sound on Early Precursors of Language.
  |
Related Articles |
Symbolic Play and Novel Noun Learning in Deaf and Hearing Children: Longitudinal Effects of Access to Sound on Early Precursors of Language.
PLoS One. 2016;11(5):e0155964
Authors: Quittner AL, Cejas I, Wang NY, Niparko JK, Barker DH
Abstract
In the largest, longitudinal study of young, deaf children before and three years after cochlear implantation, we compared symbolic play and novel noun learning to age-matched hearing peers. Participants were 180 children from six cochlear implant centers and 96 hearing children. Symbolic play was measured during five minutes of videotaped, structured solitary play. Play was coded as "symbolic" if the child used substitution (e.g., a wooden block as a bed). Novel noun learning was measured in 10 trials using a novel object and a distractor. Cochlear implant vs. normal hearing children were delayed in their use of symbolic play, however, those implanted before vs. after age two performed significantly better. Children with cochlear implants were also delayed in novel noun learning (median delay 1.54 years), with minimal evidence of catch-up growth. Quality of parent-child interactions was positively related to performance on the novel noun learning, but not symbolic play task. Early implantation was beneficial for both achievement of symbolic play and novel noun learning. Further, maternal sensitivity and linguistic stimulation by parents positively affected noun learning skills, although children with cochlear implants still lagged in comparison to hearing peers.
PMID: 27228032 [PubMed - indexed for MEDLINE]
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Using the International Classification of Functioning, Disability and Health in Assessment and Intervention of School-Aged Children With Language Impairments
Purpose
The aim of this tutorial is to support speech-language pathologists' (SLPs') application of the International Classification of Functioning, Disability and Health (ICF) in assessment and treatment practices with children with language impairment.
Method
This tutorial reviews the framework of the ICF, describes the implications of the ICF for SLPs, distinguishes between students' capacity to perform a skill in a structured context and the actual performance of that skill in naturalistic contexts, and provides a case study of an elementary school child to demonstrate how the principles of the ICF can guide assessment and intervention.
Implications
The Scope of Practice and Preferred Practice documents for the American Speech-Language-Hearing Association identify the ICF as the framework for practice in speech-language pathology. This tutorial will facilitate clinicians' ability to identify personal and environmental factors that influence students' skill capacity and skill performance, assess students' capacity and performance, and develop impairment-based and socially based language goals linked to Common Core State Standards that build students' language capacity and their communicative performance in naturalistic contexts.from #Audiology via xlomafota13 on Inoreader http://ift.tt/2tHHlfF
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English Verb Accuracy of Bilingual Cantonese–English Preschoolers
Purpose
Knowledge of verb development in typically developing bilingual preschoolers may inform clinicians about verb accuracy rates during the 1st 2 years of English instruction. This study aimed to investigate tensed verb accuracy in 2 assessment contexts in 4- and 5-year-old Cantonese–English bilingual preschoolers.
Method
The sample included 47 Cantonese–English bilinguals enrolled in English preschools. Half of the children were in their 1st 4 months of English language exposure, and half had completed 1 year and 4 months of exposure to English. Data were obtained from the Test of Early Grammatical Impairment (Rice & Wexler, 2001) and from a narrative generated in English.
Results
By the 2nd year of formal exposure to English, children in the present study approximated 33% accuracy of tensed verbs in a formal testing context versus 61% in a narrative context. The use of the English verb BE approximated mastery. Predictors of English third-person singular verb accuracy were task, grade, English expressive vocabulary, and lemma frequency.
Conclusions
Verb tense accuracy was low across both groups, but a precocious mastery of BE was observed. The results of the present study suggest that speech-language pathologists may consider, in addition to an elicitation task, evaluating the use of verbs during narratives in bilingual Cantonese–English bilingual children.from #Audiology via xlomafota13 on Inoreader http://ift.tt/2sqy3EJ
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Tense Marking in the English Narrative Retells of Dual Language Preschoolers
Purpose
This longitudinal study investigated the emergence of English tense marking in young (Spanish–English) dual language learners (DLLs) over 4 consecutive academic semesters, addressing the need for longitudinal data on typical acquisition trajectories of English in DLL preschoolers.
Method
Language sample analysis was conducted on 139 English narrative retells elicited from 39 preschool-age (Spanish–English) DLLs (range = 39–65 months). Growth curve models captured within- and between-individual change in tense-marking accuracy over time. Tense-marking accuracy was indexed by the finite verb morphology composite and by 2 specifically developed adaptations. Individual tense markers were systematically described in terms of overall accuracy and specific error patterns.
Results
Tense-marking accuracy exhibited significant growth over time for each composite. Initially, irregular past-tense accuracy was higher than regular past-tense accuracy; over time, however, regular past-tense marking outpaced accuracy on irregular verbs.
Conclusions
These findings suggest that young DLLs can achieve high tense-marking accuracy assuming 2 years of immersive exposure to English. Monitoring the growth in tense-marking accuracy over time and considering productive tense-marking errors as partially correct more precisely captured the emergence of English tense marking in this population with highly variable expressive language skills.
Supplemental Materials
http://ift.tt/2tIdOlyfrom #Audiology via xlomafota13 on Inoreader http://ift.tt/2ucf9EC
via IFTTT
Language Assessment With Children Who Speak Nonmainstream Dialects: Examining the Effects of Scoring Modifications in Norm-Referenced Assessment
Purpose
We compared outcomes from 2 measures of language ability in children who displayed a range of dialect variation: 1 using features that do not contrast between mainstream American English (MAE) and nonmainstream dialects (NMAE), and 1 using contrastive features. We investigated how modified scoring procedures affected the diagnostic accuracy of the measure with contrastive features.
Method
Second-grade students (N = 299; 167 White, 106 African American, 26 other) completed measures of language variation and ability (the Diagnostic Evaluation of Language Variation–Screening Test and the Clinical Evaluation of Language Fundamentals–Fourth Edition [CELF-4]). The CELF-4 was scored with and without the recommended scoring modifications for children who spoke African American English.
Results
Partial correlations controlling for socioeconomic status revealed small to moderate correlations between measures of language ability and the use of NMAE features. Modified scoring yielded higher scores for children who spoke African American English and a reduced association between the use of NMAE features and CELF-4 scores. Modified scoring also affected the diagnostic accuracy of the CELF-4, resulting in a lower positive likelihood ratio and a higher negative likelihood ratio.
Conclusions
The decision to apply scoring modifications affects both the false positive and false negative rates. Implications for language assessment for children who speak NMAE dialects are discussed, including the need for further investigation.from #Audiology via xlomafota13 on Inoreader http://ift.tt/2unypzR
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Resources for LSHSS Authors
Purpose
In this article, the Editor-in-Chief of Language, Speech, and Hearing Services in Schools (LSHSS) highlights key resources for authors wishing to publish their work in LSHSS.from #Audiology via ola Kala on Inoreader http://ift.tt/2tnyH65
via IFTTT
Using the International Classification of Functioning, Disability and Health in Assessment and Intervention of School-Aged Children With Language Impairments
Purpose
The aim of this tutorial is to support speech-language pathologists' (SLPs') application of the International Classification of Functioning, Disability and Health (ICF) in assessment and treatment practices with children with language impairment.
Method
This tutorial reviews the framework of the ICF, describes the implications of the ICF for SLPs, distinguishes between students' capacity to perform a skill in a structured context and the actual performance of that skill in naturalistic contexts, and provides a case study of an elementary school child to demonstrate how the principles of the ICF can guide assessment and intervention.
Implications
The Scope of Practice and Preferred Practice documents for the American Speech-Language-Hearing Association identify the ICF as the framework for practice in speech-language pathology. This tutorial will facilitate clinicians' ability to identify personal and environmental factors that influence students' skill capacity and skill performance, assess students' capacity and performance, and develop impairment-based and socially based language goals linked to Common Core State Standards that build students' language capacity and their communicative performance in naturalistic contexts.from #Audiology via ola Kala on Inoreader http://ift.tt/2tHHlfF
via IFTTT
Sampling Utterances and Grammatical Analysis Revised (SUGAR): New Normative Values for Language Sample Analysis Measures
Purpose
The purpose of this study was to document whether mean length of utterance (MLUS), total number of words (TNW), clauses per sentence (CPS), and/or words per sentence (WPS) demonstrated age-related changes in children with typical language and to document the average time to collect, transcribe, and analyze conversational language samples.
Method
Participants were 385 typically developing children (ages 3;0–7;11 [years;months]), with a final sample size of 270 participants (133 males and 137 females). Fifty-utterance conversational language samples were collected using a language sampling protocol. Four language sample analysis (LSA) metrics (i.e., MLUS, TNW, CPS, WPS) were calculated from the samples.
Results
Results indicated statistically significant age-related increases in the four metrics. The average time to collect, transcribe, and analyze each sample was 20.91 min (SD = 3.97; range = 10.55–33.37).
Conclusion
MLUS, TNW, CPS, and WPS may be used with other assessment data to document age-related changes in children's language. When used as part of an assessment, the results from all of the metrics should be considered. Considering results from only 1 individual metric is not encouraged. These results suggest LSA may be completed in approximately 20 min, which is less than the average time to administer a standardized, norm-referenced language assessment.from #Audiology via ola Kala on Inoreader http://ift.tt/2tEG5hU
via IFTTT
English Verb Accuracy of Bilingual Cantonese–English Preschoolers
Purpose
Knowledge of verb development in typically developing bilingual preschoolers may inform clinicians about verb accuracy rates during the 1st 2 years of English instruction. This study aimed to investigate tensed verb accuracy in 2 assessment contexts in 4- and 5-year-old Cantonese–English bilingual preschoolers.
Method
The sample included 47 Cantonese–English bilinguals enrolled in English preschools. Half of the children were in their 1st 4 months of English language exposure, and half had completed 1 year and 4 months of exposure to English. Data were obtained from the Test of Early Grammatical Impairment (Rice & Wexler, 2001) and from a narrative generated in English.
Results
By the 2nd year of formal exposure to English, children in the present study approximated 33% accuracy of tensed verbs in a formal testing context versus 61% in a narrative context. The use of the English verb BE approximated mastery. Predictors of English third-person singular verb accuracy were task, grade, English expressive vocabulary, and lemma frequency.
Conclusions
Verb tense accuracy was low across both groups, but a precocious mastery of BE was observed. The results of the present study suggest that speech-language pathologists may consider, in addition to an elicitation task, evaluating the use of verbs during narratives in bilingual Cantonese–English bilingual children.from #Audiology via ola Kala on Inoreader http://ift.tt/2sqy3EJ
via IFTTT
Tense Marking in the English Narrative Retells of Dual Language Preschoolers
Purpose
This longitudinal study investigated the emergence of English tense marking in young (Spanish–English) dual language learners (DLLs) over 4 consecutive academic semesters, addressing the need for longitudinal data on typical acquisition trajectories of English in DLL preschoolers.
Method
Language sample analysis was conducted on 139 English narrative retells elicited from 39 preschool-age (Spanish–English) DLLs (range = 39–65 months). Growth curve models captured within- and between-individual change in tense-marking accuracy over time. Tense-marking accuracy was indexed by the finite verb morphology composite and by 2 specifically developed adaptations. Individual tense markers were systematically described in terms of overall accuracy and specific error patterns.
Results
Tense-marking accuracy exhibited significant growth over time for each composite. Initially, irregular past-tense accuracy was higher than regular past-tense accuracy; over time, however, regular past-tense marking outpaced accuracy on irregular verbs.
Conclusions
These findings suggest that young DLLs can achieve high tense-marking accuracy assuming 2 years of immersive exposure to English. Monitoring the growth in tense-marking accuracy over time and considering productive tense-marking errors as partially correct more precisely captured the emergence of English tense marking in this population with highly variable expressive language skills.
Supplemental Materials
http://ift.tt/2tIdOlyfrom #Audiology via ola Kala on Inoreader http://ift.tt/2ucf9EC
via IFTTT
Language Assessment With Children Who Speak Nonmainstream Dialects: Examining the Effects of Scoring Modifications in Norm-Referenced Assessment
Purpose
We compared outcomes from 2 measures of language ability in children who displayed a range of dialect variation: 1 using features that do not contrast between mainstream American English (MAE) and nonmainstream dialects (NMAE), and 1 using contrastive features. We investigated how modified scoring procedures affected the diagnostic accuracy of the measure with contrastive features.
Method
Second-grade students (N = 299; 167 White, 106 African American, 26 other) completed measures of language variation and ability (the Diagnostic Evaluation of Language Variation–Screening Test and the Clinical Evaluation of Language Fundamentals–Fourth Edition [CELF-4]). The CELF-4 was scored with and without the recommended scoring modifications for children who spoke African American English.
Results
Partial correlations controlling for socioeconomic status revealed small to moderate correlations between measures of language ability and the use of NMAE features. Modified scoring yielded higher scores for children who spoke African American English and a reduced association between the use of NMAE features and CELF-4 scores. Modified scoring also affected the diagnostic accuracy of the CELF-4, resulting in a lower positive likelihood ratio and a higher negative likelihood ratio.
Conclusions
The decision to apply scoring modifications affects both the false positive and false negative rates. Implications for language assessment for children who speak NMAE dialects are discussed, including the need for further investigation.from #Audiology via ola Kala on Inoreader http://ift.tt/2unypzR
via IFTTT
Resources for LSHSS Authors
Purpose
In this article, the Editor-in-Chief of Language, Speech, and Hearing Services in Schools (LSHSS) highlights key resources for authors wishing to publish their work in LSHSS.from #Audiology via ola Kala on Inoreader http://ift.tt/2tnyH65
via IFTTT
Using the International Classification of Functioning, Disability and Health in Assessment and Intervention of School-Aged Children With Language Impairments
Purpose
The aim of this tutorial is to support speech-language pathologists' (SLPs') application of the International Classification of Functioning, Disability and Health (ICF) in assessment and treatment practices with children with language impairment.
Method
This tutorial reviews the framework of the ICF, describes the implications of the ICF for SLPs, distinguishes between students' capacity to perform a skill in a structured context and the actual performance of that skill in naturalistic contexts, and provides a case study of an elementary school child to demonstrate how the principles of the ICF can guide assessment and intervention.
Implications
The Scope of Practice and Preferred Practice documents for the American Speech-Language-Hearing Association identify the ICF as the framework for practice in speech-language pathology. This tutorial will facilitate clinicians' ability to identify personal and environmental factors that influence students' skill capacity and skill performance, assess students' capacity and performance, and develop impairment-based and socially based language goals linked to Common Core State Standards that build students' language capacity and their communicative performance in naturalistic contexts.from #Audiology via ola Kala on Inoreader http://ift.tt/2tHHlfF
via IFTTT
Sampling Utterances and Grammatical Analysis Revised (SUGAR): New Normative Values for Language Sample Analysis Measures
Purpose
The purpose of this study was to document whether mean length of utterance (MLUS), total number of words (TNW), clauses per sentence (CPS), and/or words per sentence (WPS) demonstrated age-related changes in children with typical language and to document the average time to collect, transcribe, and analyze conversational language samples.
Method
Participants were 385 typically developing children (ages 3;0–7;11 [years;months]), with a final sample size of 270 participants (133 males and 137 females). Fifty-utterance conversational language samples were collected using a language sampling protocol. Four language sample analysis (LSA) metrics (i.e., MLUS, TNW, CPS, WPS) were calculated from the samples.
Results
Results indicated statistically significant age-related increases in the four metrics. The average time to collect, transcribe, and analyze each sample was 20.91 min (SD = 3.97; range = 10.55–33.37).
Conclusion
MLUS, TNW, CPS, and WPS may be used with other assessment data to document age-related changes in children's language. When used as part of an assessment, the results from all of the metrics should be considered. Considering results from only 1 individual metric is not encouraged. These results suggest LSA may be completed in approximately 20 min, which is less than the average time to administer a standardized, norm-referenced language assessment.from #Audiology via ola Kala on Inoreader http://ift.tt/2tEG5hU
via IFTTT
English Verb Accuracy of Bilingual Cantonese–English Preschoolers
Purpose
Knowledge of verb development in typically developing bilingual preschoolers may inform clinicians about verb accuracy rates during the 1st 2 years of English instruction. This study aimed to investigate tensed verb accuracy in 2 assessment contexts in 4- and 5-year-old Cantonese–English bilingual preschoolers.
Method
The sample included 47 Cantonese–English bilinguals enrolled in English preschools. Half of the children were in their 1st 4 months of English language exposure, and half had completed 1 year and 4 months of exposure to English. Data were obtained from the Test of Early Grammatical Impairment (Rice & Wexler, 2001) and from a narrative generated in English.
Results
By the 2nd year of formal exposure to English, children in the present study approximated 33% accuracy of tensed verbs in a formal testing context versus 61% in a narrative context. The use of the English verb BE approximated mastery. Predictors of English third-person singular verb accuracy were task, grade, English expressive vocabulary, and lemma frequency.
Conclusions
Verb tense accuracy was low across both groups, but a precocious mastery of BE was observed. The results of the present study suggest that speech-language pathologists may consider, in addition to an elicitation task, evaluating the use of verbs during narratives in bilingual Cantonese–English bilingual children.from #Audiology via ola Kala on Inoreader http://ift.tt/2sqy3EJ
via IFTTT
Tense Marking in the English Narrative Retells of Dual Language Preschoolers
Purpose
This longitudinal study investigated the emergence of English tense marking in young (Spanish–English) dual language learners (DLLs) over 4 consecutive academic semesters, addressing the need for longitudinal data on typical acquisition trajectories of English in DLL preschoolers.
Method
Language sample analysis was conducted on 139 English narrative retells elicited from 39 preschool-age (Spanish–English) DLLs (range = 39–65 months). Growth curve models captured within- and between-individual change in tense-marking accuracy over time. Tense-marking accuracy was indexed by the finite verb morphology composite and by 2 specifically developed adaptations. Individual tense markers were systematically described in terms of overall accuracy and specific error patterns.
Results
Tense-marking accuracy exhibited significant growth over time for each composite. Initially, irregular past-tense accuracy was higher than regular past-tense accuracy; over time, however, regular past-tense marking outpaced accuracy on irregular verbs.
Conclusions
These findings suggest that young DLLs can achieve high tense-marking accuracy assuming 2 years of immersive exposure to English. Monitoring the growth in tense-marking accuracy over time and considering productive tense-marking errors as partially correct more precisely captured the emergence of English tense marking in this population with highly variable expressive language skills.
Supplemental Materials
http://ift.tt/2tIdOlyfrom #Audiology via ola Kala on Inoreader http://ift.tt/2ucf9EC
via IFTTT
Language Assessment With Children Who Speak Nonmainstream Dialects: Examining the Effects of Scoring Modifications in Norm-Referenced Assessment
Purpose
We compared outcomes from 2 measures of language ability in children who displayed a range of dialect variation: 1 using features that do not contrast between mainstream American English (MAE) and nonmainstream dialects (NMAE), and 1 using contrastive features. We investigated how modified scoring procedures affected the diagnostic accuracy of the measure with contrastive features.
Method
Second-grade students (N = 299; 167 White, 106 African American, 26 other) completed measures of language variation and ability (the Diagnostic Evaluation of Language Variation–Screening Test and the Clinical Evaluation of Language Fundamentals–Fourth Edition [CELF-4]). The CELF-4 was scored with and without the recommended scoring modifications for children who spoke African American English.
Results
Partial correlations controlling for socioeconomic status revealed small to moderate correlations between measures of language ability and the use of NMAE features. Modified scoring yielded higher scores for children who spoke African American English and a reduced association between the use of NMAE features and CELF-4 scores. Modified scoring also affected the diagnostic accuracy of the CELF-4, resulting in a lower positive likelihood ratio and a higher negative likelihood ratio.
Conclusions
The decision to apply scoring modifications affects both the false positive and false negative rates. Implications for language assessment for children who speak NMAE dialects are discussed, including the need for further investigation.from #Audiology via ola Kala on Inoreader http://ift.tt/2unypzR
via IFTTT
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