Παρασκευή 22 Σεπτεμβρίου 2017

Validating a Rapid, Automated Test of Spatial Release From Masking

Purpose
To evaluate the test–retest reliability of a headphone-based spatial release from a masking task with two maskers (referred to here as the SR2) and to describe its relationship to the same test done over loudspeakers in an anechoic chamber (the SR2A). We explore what thresholds tell us about certain populations (such as older individuals or individuals with hearing impairment) and discuss how the SR2 might be useful in the clinic.
Method
Fifty-four participants completed speech intelligibility tests in which a target phrase and two masking phrases from the Coordinate Response Measure corpus (Bolia, Nelson, Ericson, & Simpson, 2000) were presented either via earphones using a virtual spatial array or via loudspeakers in an anechoic chamber. For the SR2, the target sentence was always at 0° azimuth angle, and the maskers were either colocated at 0° or positioned at ± 45°. For the SR2A, the target was located at 0°, and the maskers were colocated or located at ± 15°, ± 30°, ± 45°, ± 90°, or ± 135°. Spatial release from masking was determined as the difference between thresholds in the colocated condition and each spatially separated condition. All participants completed the SR2 at least twice, and 29 of the individuals who completed the SR2 at least twice also participated in the SR2A. In a second experiment, 40 participants completed the SR2 8 times, and the changes in performance were evaluated as a function of test repetition.
Results
Mean thresholds were slightly better on the SR2 after the first repetition but were consistent across 8 subsequent testing sessions. Performance was consistent for the SR2A, regardless of the number of times testing was repeated. The SR2, which simulates 45° separations of target and maskers, produced spatially separated thresholds that were similar to thresholds obtained with 30° of separation in the anechoic chamber. Over headphones and in the anechoic chamber, pure-tone average was a strong predictor of spatial release, whereas age only reached significance for colocated conditions.
Conclusions
The SR2 is a reliable and effective method of testing spatial release from masking, suitable for screening abnormal listening abilities and for tracking rehabilitation over time. Future work should focus on developing and validating rapid, automated testing to identify the ability of listeners to benefit from high-frequency amplification, smaller spatial separations, and larger spectral differences among talkers.

from #Audiology via ola Kala on Inoreader http://article/doi/10.1044/2017_AJA-17-0013/2655026/Validating-a-Rapid-Automated-Test-of-Spatial
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Characteristics and Treatment Outcomes of Benign Paroxysmal Positional Vertigo in a Cohort of Veterans

Background
The Mountain Home Veterans Affairs (VA) Medical Center has been diagnosing and treating veterans with benign paroxysmal positional vertigo (BPPV) for almost 2 decades. The clinic protocol includes a 2-week follow-up visit to determine the treatment outcome of the canalith repositioning treatment (CRT). To date, the characteristics of BPPV and treatment efficacy have not been reported in a cohort of veterans with BPPV.
Purpose
To determine the prevalence and characteristics of veterans diagnosed with BPPV in a Veterans Affairs Medical Center Audiology Clinic and to examine treatment outcomes.
Research Design
Retrospective chart review.
Study Sample
A total of 102 veterans who tested positive for BPPV in the Vestibular Clinic at the Mountain Home VA Medical Center from March 2010 to August 2011.
Results
In 102 veterans who were diagnosed with BPPV, the posterior semicircular canal was most often involved (75%), motion-provoked vertigo was the most common symptom (84%), and the majority (43%) were diagnosed with BPPV in their sixth decade. The prevalence of BPPV in the Audiology Vestibular Clinic was 15.6%. Forty-one percent of veterans reported a symptom onset within 12 months of treatment for BPPV; however, 36% reported their symptoms began > 36 months prior to treatment. CRT was effective (negative Dix–Hallpike/roll test) in most veterans (86%) following 1 treatment appointment (M = 1.6), but more than half reported incomplete symptom resolution (residual dizziness) at the follow-up appointment. Eighteen percent of veterans experienced a recurrence (M = 1.8 years; SD = 1.7 years).
Conclusions
The characteristics and treatment outcomes of BPPV in our veteran cohort was similar to what has been reported in the general population. Future work should focus on improving the timeliness of evaluation and treatment of BPPV and examining the time course and management of residual dizziness.

from #Audiology via ola Kala on Inoreader http://article/doi/10.1044/2017_AJA-16-0118/2654846/Characteristics-and-Treatment-Outcomes-of-Benign
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Validating a Rapid, Automated Test of Spatial Release From Masking

Purpose
To evaluate the test–retest reliability of a headphone-based spatial release from a masking task with two maskers (referred to here as the SR2) and to describe its relationship to the same test done over loudspeakers in an anechoic chamber (the SR2A). We explore what thresholds tell us about certain populations (such as older individuals or individuals with hearing impairment) and discuss how the SR2 might be useful in the clinic.
Method
Fifty-four participants completed speech intelligibility tests in which a target phrase and two masking phrases from the Coordinate Response Measure corpus (Bolia, Nelson, Ericson, & Simpson, 2000) were presented either via earphones using a virtual spatial array or via loudspeakers in an anechoic chamber. For the SR2, the target sentence was always at 0° azimuth angle, and the maskers were either colocated at 0° or positioned at ± 45°. For the SR2A, the target was located at 0°, and the maskers were colocated or located at ± 15°, ± 30°, ± 45°, ± 90°, or ± 135°. Spatial release from masking was determined as the difference between thresholds in the colocated condition and each spatially separated condition. All participants completed the SR2 at least twice, and 29 of the individuals who completed the SR2 at least twice also participated in the SR2A. In a second experiment, 40 participants completed the SR2 8 times, and the changes in performance were evaluated as a function of test repetition.
Results
Mean thresholds were slightly better on the SR2 after the first repetition but were consistent across 8 subsequent testing sessions. Performance was consistent for the SR2A, regardless of the number of times testing was repeated. The SR2, which simulates 45° separations of target and maskers, produced spatially separated thresholds that were similar to thresholds obtained with 30° of separation in the anechoic chamber. Over headphones and in the anechoic chamber, pure-tone average was a strong predictor of spatial release, whereas age only reached significance for colocated conditions.
Conclusions
The SR2 is a reliable and effective method of testing spatial release from masking, suitable for screening abnormal listening abilities and for tracking rehabilitation over time. Future work should focus on developing and validating rapid, automated testing to identify the ability of listeners to benefit from high-frequency amplification, smaller spatial separations, and larger spectral differences among talkers.

from #Audiology via ola Kala on Inoreader http://article/doi/10.1044/2017_AJA-17-0013/2655026/Validating-a-Rapid-Automated-Test-of-Spatial
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Characteristics and Treatment Outcomes of Benign Paroxysmal Positional Vertigo in a Cohort of Veterans

Background
The Mountain Home Veterans Affairs (VA) Medical Center has been diagnosing and treating veterans with benign paroxysmal positional vertigo (BPPV) for almost 2 decades. The clinic protocol includes a 2-week follow-up visit to determine the treatment outcome of the canalith repositioning treatment (CRT). To date, the characteristics of BPPV and treatment efficacy have not been reported in a cohort of veterans with BPPV.
Purpose
To determine the prevalence and characteristics of veterans diagnosed with BPPV in a Veterans Affairs Medical Center Audiology Clinic and to examine treatment outcomes.
Research Design
Retrospective chart review.
Study Sample
A total of 102 veterans who tested positive for BPPV in the Vestibular Clinic at the Mountain Home VA Medical Center from March 2010 to August 2011.
Results
In 102 veterans who were diagnosed with BPPV, the posterior semicircular canal was most often involved (75%), motion-provoked vertigo was the most common symptom (84%), and the majority (43%) were diagnosed with BPPV in their sixth decade. The prevalence of BPPV in the Audiology Vestibular Clinic was 15.6%. Forty-one percent of veterans reported a symptom onset within 12 months of treatment for BPPV; however, 36% reported their symptoms began > 36 months prior to treatment. CRT was effective (negative Dix–Hallpike/roll test) in most veterans (86%) following 1 treatment appointment (M = 1.6), but more than half reported incomplete symptom resolution (residual dizziness) at the follow-up appointment. Eighteen percent of veterans experienced a recurrence (M = 1.8 years; SD = 1.7 years).
Conclusions
The characteristics and treatment outcomes of BPPV in our veteran cohort was similar to what has been reported in the general population. Future work should focus on improving the timeliness of evaluation and treatment of BPPV and examining the time course and management of residual dizziness.

from #Audiology via ola Kala on Inoreader http://article/doi/10.1044/2017_AJA-16-0118/2654846/Characteristics-and-Treatment-Outcomes-of-Benign
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Validating a Rapid, Automated Test of Spatial Release From Masking

Purpose
To evaluate the test–retest reliability of a headphone-based spatial release from a masking task with two maskers (referred to here as the SR2) and to describe its relationship to the same test done over loudspeakers in an anechoic chamber (the SR2A). We explore what thresholds tell us about certain populations (such as older individuals or individuals with hearing impairment) and discuss how the SR2 might be useful in the clinic.
Method
Fifty-four participants completed speech intelligibility tests in which a target phrase and two masking phrases from the Coordinate Response Measure corpus (Bolia, Nelson, Ericson, & Simpson, 2000) were presented either via earphones using a virtual spatial array or via loudspeakers in an anechoic chamber. For the SR2, the target sentence was always at 0° azimuth angle, and the maskers were either colocated at 0° or positioned at ± 45°. For the SR2A, the target was located at 0°, and the maskers were colocated or located at ± 15°, ± 30°, ± 45°, ± 90°, or ± 135°. Spatial release from masking was determined as the difference between thresholds in the colocated condition and each spatially separated condition. All participants completed the SR2 at least twice, and 29 of the individuals who completed the SR2 at least twice also participated in the SR2A. In a second experiment, 40 participants completed the SR2 8 times, and the changes in performance were evaluated as a function of test repetition.
Results
Mean thresholds were slightly better on the SR2 after the first repetition but were consistent across 8 subsequent testing sessions. Performance was consistent for the SR2A, regardless of the number of times testing was repeated. The SR2, which simulates 45° separations of target and maskers, produced spatially separated thresholds that were similar to thresholds obtained with 30° of separation in the anechoic chamber. Over headphones and in the anechoic chamber, pure-tone average was a strong predictor of spatial release, whereas age only reached significance for colocated conditions.
Conclusions
The SR2 is a reliable and effective method of testing spatial release from masking, suitable for screening abnormal listening abilities and for tracking rehabilitation over time. Future work should focus on developing and validating rapid, automated testing to identify the ability of listeners to benefit from high-frequency amplification, smaller spatial separations, and larger spectral differences among talkers.

from #Audiology via xlomafota13 on Inoreader http://article/doi/10.1044/2017_AJA-17-0013/2655026/Validating-a-Rapid-Automated-Test-of-Spatial
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Characteristics and Treatment Outcomes of Benign Paroxysmal Positional Vertigo in a Cohort of Veterans

Background
The Mountain Home Veterans Affairs (VA) Medical Center has been diagnosing and treating veterans with benign paroxysmal positional vertigo (BPPV) for almost 2 decades. The clinic protocol includes a 2-week follow-up visit to determine the treatment outcome of the canalith repositioning treatment (CRT). To date, the characteristics of BPPV and treatment efficacy have not been reported in a cohort of veterans with BPPV.
Purpose
To determine the prevalence and characteristics of veterans diagnosed with BPPV in a Veterans Affairs Medical Center Audiology Clinic and to examine treatment outcomes.
Research Design
Retrospective chart review.
Study Sample
A total of 102 veterans who tested positive for BPPV in the Vestibular Clinic at the Mountain Home VA Medical Center from March 2010 to August 2011.
Results
In 102 veterans who were diagnosed with BPPV, the posterior semicircular canal was most often involved (75%), motion-provoked vertigo was the most common symptom (84%), and the majority (43%) were diagnosed with BPPV in their sixth decade. The prevalence of BPPV in the Audiology Vestibular Clinic was 15.6%. Forty-one percent of veterans reported a symptom onset within 12 months of treatment for BPPV; however, 36% reported their symptoms began > 36 months prior to treatment. CRT was effective (negative Dix–Hallpike/roll test) in most veterans (86%) following 1 treatment appointment (M = 1.6), but more than half reported incomplete symptom resolution (residual dizziness) at the follow-up appointment. Eighteen percent of veterans experienced a recurrence (M = 1.8 years; SD = 1.7 years).
Conclusions
The characteristics and treatment outcomes of BPPV in our veteran cohort was similar to what has been reported in the general population. Future work should focus on improving the timeliness of evaluation and treatment of BPPV and examining the time course and management of residual dizziness.

from #Audiology via xlomafota13 on Inoreader http://article/doi/10.1044/2017_AJA-16-0118/2654846/Characteristics-and-Treatment-Outcomes-of-Benign
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How African American English-Speaking First Graders Segment and Rhyme Words and Nonwords With Final Consonant Clusters

Purpose
This study explored how typically developing 1st grade African American English (AAE) speakers differ from mainstream American English (MAE) speakers in the completion of 2 common phonological awareness tasks (rhyming and phoneme segmentation) when the stimulus items were consonant–vowel–consonant–consonant (CVCC) words and nonwords.
Method
Forty-nine 1st graders met criteria for 2 dialect groups: AAE and MAE. Three conditions were tested in each rhyme and segmentation task: Real Words No Model, Real Words With a Model, and Nonwords With a Model.
Results
The AAE group had significantly more responses that rhymed CVCC words with consonant–vowel–consonant words and segmented CVCC words as consonant–vowel–consonant than the MAE group across all experimental conditions. In the rhyming task, the presence of a model in the real word condition elicited more reduced final cluster responses for both groups. In the segmentation task, the MAE group was at ceiling, so only the AAE group changed across the different stimulus presentations and reduced the final cluster less often when given a model.
Conclusion
Rhyming and phoneme segmentation performance can be influenced by a child's dialect when CVCC words are used.

from #Audiology via ola Kala on Inoreader http://article/doi/10.1044/2017_LSHSS-16-0062/2655088/How-African-American-EnglishSpeaking-First-Graders
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Emergent Literacy Skills in Preschool Children With Hearing Loss Who Use Spoken Language: Initial Findings From the Early Language and Literacy Acquisition (ELLA) Study

Purpose
The purpose of this study was to compare change in emergent literacy skills of preschool children with and without hearing loss over a 6-month period.
Method
Participants included 19 children with hearing loss and 14 children with normal hearing. Children with hearing loss used amplification and spoken language. Participants completed measures of oral language, phonological processing, and print knowledge twice at a 6-month interval. A series of repeated-measures analyses of variance were used to compare change across groups.
Results
Main effects of time were observed for all variables except phonological recoding. Main effects of group were observed for vocabulary, morphosyntax, phonological memory, and concepts of print. Interaction effects were observed for phonological awareness and concepts of print.
Conclusions
Children with hearing loss performed more poorly than children with normal hearing on measures of oral language, phonological memory, and conceptual print knowledge. Two interaction effects were present. For phonological awareness and concepts of print, children with hearing loss demonstrated less positive change than children with normal hearing. Although children with hearing loss generally demonstrated a positive growth in emergent literacy skills, their initial performance was lower than that of children with normal hearing, and rates of change were not sufficient to catch up to the peers over time.

from #Audiology via ola Kala on Inoreader http://article/doi/10.1044/2017_LSHSS-17-0023/2655089/Emergent-Literacy-Skills-in-Preschool-Children
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How African American English-Speaking First Graders Segment and Rhyme Words and Nonwords With Final Consonant Clusters

Purpose
This study explored how typically developing 1st grade African American English (AAE) speakers differ from mainstream American English (MAE) speakers in the completion of 2 common phonological awareness tasks (rhyming and phoneme segmentation) when the stimulus items were consonant–vowel–consonant–consonant (CVCC) words and nonwords.
Method
Forty-nine 1st graders met criteria for 2 dialect groups: AAE and MAE. Three conditions were tested in each rhyme and segmentation task: Real Words No Model, Real Words With a Model, and Nonwords With a Model.
Results
The AAE group had significantly more responses that rhymed CVCC words with consonant–vowel–consonant words and segmented CVCC words as consonant–vowel–consonant than the MAE group across all experimental conditions. In the rhyming task, the presence of a model in the real word condition elicited more reduced final cluster responses for both groups. In the segmentation task, the MAE group was at ceiling, so only the AAE group changed across the different stimulus presentations and reduced the final cluster less often when given a model.
Conclusion
Rhyming and phoneme segmentation performance can be influenced by a child's dialect when CVCC words are used.

from #Audiology via xlomafota13 on Inoreader http://article/doi/10.1044/2017_LSHSS-16-0062/2655088/How-African-American-EnglishSpeaking-First-Graders
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Emergent Literacy Skills in Preschool Children With Hearing Loss Who Use Spoken Language: Initial Findings From the Early Language and Literacy Acquisition (ELLA) Study

Purpose
The purpose of this study was to compare change in emergent literacy skills of preschool children with and without hearing loss over a 6-month period.
Method
Participants included 19 children with hearing loss and 14 children with normal hearing. Children with hearing loss used amplification and spoken language. Participants completed measures of oral language, phonological processing, and print knowledge twice at a 6-month interval. A series of repeated-measures analyses of variance were used to compare change across groups.
Results
Main effects of time were observed for all variables except phonological recoding. Main effects of group were observed for vocabulary, morphosyntax, phonological memory, and concepts of print. Interaction effects were observed for phonological awareness and concepts of print.
Conclusions
Children with hearing loss performed more poorly than children with normal hearing on measures of oral language, phonological memory, and conceptual print knowledge. Two interaction effects were present. For phonological awareness and concepts of print, children with hearing loss demonstrated less positive change than children with normal hearing. Although children with hearing loss generally demonstrated a positive growth in emergent literacy skills, their initial performance was lower than that of children with normal hearing, and rates of change were not sufficient to catch up to the peers over time.

from #Audiology via xlomafota13 on Inoreader http://article/doi/10.1044/2017_LSHSS-17-0023/2655089/Emergent-Literacy-Skills-in-Preschool-Children
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How African American English-Speaking First Graders Segment and Rhyme Words and Nonwords With Final Consonant Clusters

Purpose
This study explored how typically developing 1st grade African American English (AAE) speakers differ from mainstream American English (MAE) speakers in the completion of 2 common phonological awareness tasks (rhyming and phoneme segmentation) when the stimulus items were consonant–vowel–consonant–consonant (CVCC) words and nonwords.
Method
Forty-nine 1st graders met criteria for 2 dialect groups: AAE and MAE. Three conditions were tested in each rhyme and segmentation task: Real Words No Model, Real Words With a Model, and Nonwords With a Model.
Results
The AAE group had significantly more responses that rhymed CVCC words with consonant–vowel–consonant words and segmented CVCC words as consonant–vowel–consonant than the MAE group across all experimental conditions. In the rhyming task, the presence of a model in the real word condition elicited more reduced final cluster responses for both groups. In the segmentation task, the MAE group was at ceiling, so only the AAE group changed across the different stimulus presentations and reduced the final cluster less often when given a model.
Conclusion
Rhyming and phoneme segmentation performance can be influenced by a child's dialect when CVCC words are used.

from #Audiology via ola Kala on Inoreader http://article/doi/10.1044/2017_LSHSS-16-0062/2655088/How-African-American-EnglishSpeaking-First-Graders
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Emergent Literacy Skills in Preschool Children With Hearing Loss Who Use Spoken Language: Initial Findings From the Early Language and Literacy Acquisition (ELLA) Study

Purpose
The purpose of this study was to compare change in emergent literacy skills of preschool children with and without hearing loss over a 6-month period.
Method
Participants included 19 children with hearing loss and 14 children with normal hearing. Children with hearing loss used amplification and spoken language. Participants completed measures of oral language, phonological processing, and print knowledge twice at a 6-month interval. A series of repeated-measures analyses of variance were used to compare change across groups.
Results
Main effects of time were observed for all variables except phonological recoding. Main effects of group were observed for vocabulary, morphosyntax, phonological memory, and concepts of print. Interaction effects were observed for phonological awareness and concepts of print.
Conclusions
Children with hearing loss performed more poorly than children with normal hearing on measures of oral language, phonological memory, and conceptual print knowledge. Two interaction effects were present. For phonological awareness and concepts of print, children with hearing loss demonstrated less positive change than children with normal hearing. Although children with hearing loss generally demonstrated a positive growth in emergent literacy skills, their initial performance was lower than that of children with normal hearing, and rates of change were not sufficient to catch up to the peers over time.

from #Audiology via ola Kala on Inoreader http://article/doi/10.1044/2017_LSHSS-17-0023/2655089/Emergent-Literacy-Skills-in-Preschool-Children
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The heterospecific calling song can improve conspecific signal detection in a bushcricket species

grey_pxl.gif

Publication date: Available online 21 September 2017
Source:Hearing Research
Author(s): Zainab A.S. Abdelatti, Manfred Hartbauer
In forest clearings of the Malaysian rainforest, chirping and trilling Mecopoda species often live in sympatry. We investigated whether a phenomenon known as stochastic resonance (SR) improved the ability of individuals to detect a low-frequent signal component typical of chirps when members of the heterospecific trilling species were simultaneously active. This phenomenon may explain the fact that the chirping species upholds entrainment to the conspecific song in the presence of the trill. Therefore, we evaluated the response probability of an ascending auditory neuron (TN-1) in individuals of the chirping Mecopoda species to triple-pulsed 2, 8 and 20 kHz signals that were broadcast 1 dB below the hearing threshold while increasing the intensity of either white noise or a typical triller song.Our results demonstrate the existence of SR over a rather broad range of signal-to-noise ratios (SNRs) of input signals when periodic 2 kHz and 20 kHz signals were presented at the same time as white noise. Using the chirp-specific 2 kHz signal as a stimulus, the maximum TN-1 response probability frequently exceeded the 50% threshold if the trill was broadcast simultaneously. Playback of an 8 kHz signal, a common frequency band component of the trill, yielded a similar result. Nevertheless, using the trill as a masker, the signal-related TN-1 spiking probability was rather variable. The variability on an individual level resulted from correlations between the phase relationship of the signal and syllables of the trill. For the first time, these results demonstrate the existence of SR in acoustically-communicating insects and suggest that the calling song of heterospecifics may facilitate the detection of a subthreshold signal component in certain situations. The results of the simulation of sound propagation in a computer model suggest a wide range of sender-receiver distances in which the triller can help to improve the detection of subthreshold signals in the chirping species.



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Pulsatile tinnitus: Causes, symptoms, and treatment

Tinnitus is where a person hears sounds within the ear, such as ringing. Pulsatile tinnitus is when the sounds are in time to the beat of their pulse.

from #Audiology via xlomafota13 on Inoreader http://ift.tt/2jR4Rqw
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The heterospecific calling song can improve conspecific signal detection in a bushcricket species

grey_pxl.gif

Publication date: Available online 21 September 2017
Source:Hearing Research
Author(s): Zainab A.S. Abdelatti, Manfred Hartbauer
In forest clearings of the Malaysian rainforest, chirping and trilling Mecopoda species often live in sympatry. We investigated whether a phenomenon known as stochastic resonance (SR) improved the ability of individuals to detect a low-frequent signal component typical of chirps when members of the heterospecific trilling species were simultaneously active. This phenomenon may explain the fact that the chirping species upholds entrainment to the conspecific song in the presence of the trill. Therefore, we evaluated the response probability of an ascending auditory neuron (TN-1) in individuals of the chirping Mecopoda species to triple-pulsed 2, 8 and 20 kHz signals that were broadcast 1 dB below the hearing threshold while increasing the intensity of either white noise or a typical triller song.Our results demonstrate the existence of SR over a rather broad range of signal-to-noise ratios (SNRs) of input signals when periodic 2 kHz and 20 kHz signals were presented at the same time as white noise. Using the chirp-specific 2 kHz signal as a stimulus, the maximum TN-1 response probability frequently exceeded the 50% threshold if the trill was broadcast simultaneously. Playback of an 8 kHz signal, a common frequency band component of the trill, yielded a similar result. Nevertheless, using the trill as a masker, the signal-related TN-1 spiking probability was rather variable. The variability on an individual level resulted from correlations between the phase relationship of the signal and syllables of the trill. For the first time, these results demonstrate the existence of SR in acoustically-communicating insects and suggest that the calling song of heterospecifics may facilitate the detection of a subthreshold signal component in certain situations. The results of the simulation of sound propagation in a computer model suggest a wide range of sender-receiver distances in which the triller can help to improve the detection of subthreshold signals in the chirping species.



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The heterospecific calling song can improve conspecific signal detection in a bushcricket species

grey_pxl.gif

Publication date: Available online 21 September 2017
Source:Hearing Research
Author(s): Zainab A.S. Abdelatti, Manfred Hartbauer
In forest clearings of the Malaysian rainforest, chirping and trilling Mecopoda species often live in sympatry. We investigated whether a phenomenon known as stochastic resonance (SR) improved the ability of individuals to detect a low-frequent signal component typical of chirps when members of the heterospecific trilling species were simultaneously active. This phenomenon may explain the fact that the chirping species upholds entrainment to the conspecific song in the presence of the trill. Therefore, we evaluated the response probability of an ascending auditory neuron (TN-1) in individuals of the chirping Mecopoda species to triple-pulsed 2, 8 and 20 kHz signals that were broadcast 1 dB below the hearing threshold while increasing the intensity of either white noise or a typical triller song.Our results demonstrate the existence of SR over a rather broad range of signal-to-noise ratios (SNRs) of input signals when periodic 2 kHz and 20 kHz signals were presented at the same time as white noise. Using the chirp-specific 2 kHz signal as a stimulus, the maximum TN-1 response probability frequently exceeded the 50% threshold if the trill was broadcast simultaneously. Playback of an 8 kHz signal, a common frequency band component of the trill, yielded a similar result. Nevertheless, using the trill as a masker, the signal-related TN-1 spiking probability was rather variable. The variability on an individual level resulted from correlations between the phase relationship of the signal and syllables of the trill. For the first time, these results demonstrate the existence of SR in acoustically-communicating insects and suggest that the calling song of heterospecifics may facilitate the detection of a subthreshold signal component in certain situations. The results of the simulation of sound propagation in a computer model suggest a wide range of sender-receiver distances in which the triller can help to improve the detection of subthreshold signals in the chirping species.



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Pulsatile tinnitus: Causes, symptoms, and treatment

Tinnitus is where a person hears sounds within the ear, such as ringing. Pulsatile tinnitus is when the sounds are in time to the beat of their pulse.

from #Audiology via ola Kala on Inoreader http://ift.tt/2jR4Rqw
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Pulsatile tinnitus: Causes, symptoms, and treatment

Tinnitus is where a person hears sounds within the ear, such as ringing. Pulsatile tinnitus is when the sounds are in time to the beat of their pulse.

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Does Standing at Work Help Performance?

How much time do you spend sitting every day? Between commuting, working, eating, watching tv, etc., the sedentary hours add up. The negative health effects of long hours of sit time are fairly well known and include chronic disease, and psychological concerns. Seeing a potential market, several companies designed standing workstations, even desks with treadmills attached. While these sit-to-stand desks are trending, is there any evidence to support their use?



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