Hearing Research
Origins of thalamic and cortical projections to the posterior auditory field in congenitally deaf cats
Tuesday, June 14, 2016, 11:30
Publication date: Available online 13 June 2016
Source:Hearing Research
Author(s): Blake E. Butler, Nicole Chabot, Andrej Kral, Stephen G. Lomber
Crossmodal plasticity takes place following sensory loss, such that areas that normally process the missing modality are reorganized to provide compensatory function in the remaining sensory systems. For example, congenitally deaf cats outperform normal hearing animals on localization of visual stimuli presented in the periphery, and this advantage has been shown to be mediated by the posterior auditory field (PAF). In order to determine the nature of the anatomical differences that underlie this phenomenon, we injected a retrograde tracer into PAF of congenitally deaf animals and quantified the thalamic and cortical projections to this field. The pattern of projections from areas throughout the brain was determined to be qualitatively similar to that previously demonstrated in normal hearing animals, but with twice as many projections arising from non-auditory cortical areas. In addition, small ectopic projections were observed from a number of fields in visual cortex, including areas 19, 20a, 20b, and 21b, and area 7 of parietal cortex. These areas did not show projections to PAF in cats deafened ototoxically near the onset of hearing, and provide a possible mechanism for crossmodal reorganization of PAF. These, along with the possible contributions of other mechanisms, are considered.
Source:Hearing Research
Author(s): Blake E. Butler, Nicole Chabot, Andrej Kral, Stephen G. Lomber
Crossmodal plasticity takes place following sensory loss, such that areas that normally process the missing modality are reorganized to provide compensatory function in the remaining sensory systems. For example, congenitally deaf cats outperform normal hearing animals on localization of visual stimuli presented in the periphery, and this advantage has been shown to be mediated by the posterior auditory field (PAF). In order to determine the nature of the anatomical differences that underlie this phenomenon, we injected a retrograde tracer into PAF of congenitally deaf animals and quantified the thalamic and cortical projections to this field. The pattern of projections from areas throughout the brain was determined to be qualitatively similar to that previously demonstrated in normal hearing animals, but with twice as many projections arising from non-auditory cortical areas. In addition, small ectopic projections were observed from a number of fields in visual cortex, including areas 19, 20a, 20b, and 21b, and area 7 of parietal cortex. These areas did not show projections to PAF in cats deafened ototoxically near the onset of hearing, and provide a possible mechanism for crossmodal reorganization of PAF. These, along with the possible contributions of other mechanisms, are considered.
Tags: Hearing and Balance
The Journal of the Acoustical Society of America: JASA EXPRESS LETTERS
Measured depth-dependence of waveguide invariant in shallow water with a summer profile
Altan Turgut, Laurie T. Fialkowski And Jeffrey A. Schindall · Tuesday, June 14, 2016, 0:04
Acoustic-intensity striation patterns were measured in the time-frequency domain using an L-shaped array and two simultaneously towed broadband (350–650 Hz) sources at depths above and below the thermocline under summer profile conditions. Distributions of the waveguide invariant parameter β, extracted from the acoustic striation patterns,peak at different values when receivers are above or below the thermocline for a sourcethat is below the thermocline. However, the distributions show similar characteristics when the source is above the thermocline. Experimental results are verified by a numerical analysis of phase slowness, group slowness, and relative amplitudes of acoustic modes.
Tags: Hearing and Balance
The Journal of the Acoustical Society of America: Most Recent Articles
Measured depth-dependence of waveguide invariant in shallow water with a summer profile
Altan Turgut, Laurie T. Fialkowski And Jeffrey A. Schindall · Monday, June 13, 2016, 23:26
Acoustic-intensity striation patterns were measured in the time-frequency domain using an L-shaped array and two simultaneously towed broadband (350–650 Hz) sources at depths above and below the thermocline under summer profile conditions. Distributions of the waveguide invariant parameter β, extracted from the acoustic striation patterns,peak at different values when receivers are above or below the thermocline for a sourcethat is below the thermocline. However, the distributions show similar characteristics when the source is above the thermocline. Experimental results are verified by a numerical analysis of phase slowness, group slowness, and relative amplitudes of acoustic modes.
Tags: Hearing and Balance
The Journal of the Acoustical Society of America: Most Recent Articles
Effect of acoustic fine structure cues on the recognition of auditory-only and audiovisual speech
Hartmut Meister, Katrin Fuersen, Stefan Schreitmueller And Martin Walger · Monday, June 13, 2016, 23:26
This study addressed the hypothesis that an improvement in speech recognition due to combined envelope and fine structure cues is greater in the audiovisual than the auditory modality. Normal hearing listeners were presented with envelope vocoded speech in combination with low-pass filtered speech. The benefit of adding acoustic low-frequency fine structure to acoustic envelope cues was significantly greater for audiovisual than for auditory-only speech. It is suggested that this is due to complementary information of the different acoustic and visual cues. The results have potential implications for the assessment of bimodal cochlear implant fittings or electroacoustic stimulation.
Tags: Hearing and Balance
The Journal of the Acoustical Society of America
Measured depth-dependence of waveguide invariant in shallow water with a summer profile
Altan Turgut, Laurie T. Fialkowski And Jeffrey A. Schindall · Monday, June 13, 2016, 20:02
Acoustic-intensity striation patterns were measured in the time-frequency domain using an L-shaped array and two simultaneously towed broadband (350–650 Hz) sources at depths above and below the thermocline under summer profile conditions. Distributions of the waveguide invariant parameter β, extracted from the acoustic striation patterns,peak at different values when receivers are above or below the thermocline for a sourcethat is below the thermocline. However, the distributions show similar characteristics when the source is above the thermocline. Experimental results are verified by a numerical analysis of phase slowness, group slowness, and relative amplitudes of acoustic modes.
Tags: Hearing and Balance
The Journal of the Acoustical Society of America
Effect of acoustic fine structure cues on the recognition of auditory-only and audiovisual speech
Hartmut Meister, Katrin Fuersen, Stefan Schreitmueller And Martin Walger · Monday, June 13, 2016, 20:02
This study addressed the hypothesis that an improvement in speech recognition due to combined envelope and fine structure cues is greater in the audiovisual than the auditory modality. Normal hearing listeners were presented with envelope vocoded speech in combination with low-pass filtered speech. The benefit of adding acoustic low-frequency fine structure to acoustic envelope cues was significantly greater for audiovisual than for auditory-only speech. It is suggested that this is due to complementary information of the different acoustic and visual cues. The results have potential implications for the assessment of bimodal cochlear implant fittings or electroacoustic stimulation.
Tags: Hearing and Balance
Audiology
20Q: Pediatric Vestibular Disorders and the Role of the Audiologist
Monday, June 13, 2016, 7:24
1. Pediatric assessment of dizziness? That's something new for me. It's new for a lot of us, but truth be told, there has never been a more exciting time to be in this area of Audiology. New research in pediatric vestibular assessment and management has opened our eyes to the developmental consequences of balance impairments. 2. You say "developmental"—I remember something about the vestibular system having several end organs? Right you are! In fact, there are five organs in the peripheral vestibular system with each one serving a different purpose. These five organs (three semicircular canals and two otolith organs) are connected to the two branches of the vestibular nerve (i.e. inferior and superior). All five end organs are functional at birth.
Tags: Hearing and Balance
American Academy of Audiology
Perceptions of Internet Delivery of Hearing Aids
Jacobson, Gary P. · Sunday, June 12, 2016, 13:28
Tags: Hearing and Balance
American Academy of Audiology
Clinical Outcomes of the Cochlear™ Nucleus® 5 Cochlear Implant System and SmartSound™ 2 Signal Processing
Runge, Christina L. · Sunday, June 12, 2016, 13:28
Tags: Hearing and Balance
American Academy of Audiology
Perceptions Toward Internet-Based Delivery of Hearing Aids among Older Hearing-Impaired Adults
Chandra, Navshika · Sunday, June 12, 2016, 13:28
Tags: Hearing and Balance
American Academy of Audiology
The Dichotic Digits difference Test (DDdT): Development, Normative Data, and Test‐Retest Reliability Studies Part 1
Cameron, Sharon · Sunday, June 12, 2016, 13:28
Tags: Hearing and Balance
American Academy of Audiology
Investigating the Interaction between Dichotic Deficits and Cognitive Abilities Using the Dichotic Digits difference Test (DDdT) Part 2
Cameron, Sharon · Sunday, June 12, 2016, 13:28
Tags: Hearing and Balance
American Academy of Audiology
Factors Affecting Speech Discrimination in Children with Cochlear Implants: Evidence from Early-Implanted Infants
Phan, Jennifer · Sunday, June 12, 2016, 13:28
Tags: Hearing and Balance
American Academy of Audiology
Perception of Small Frequency Differences in Children with Auditory Processing Disorder or Specific Language Impairment
Rota-donahue, Christine · Sunday, June 12, 2016, 13:28
Tags: Hearing and Balance
Gait & Posture
Required coefficient of friction during level walking is predictive of slipping
Saturday, June 11, 2016, 15:24
Publication date: Available online 11 June 2016
Source:Gait & Posture
Author(s): Kurt E. Beschorner, Devon L. Albert, Mark S. Redfern
The required coefficient of friction (RCOF) is frequently reported in the literature as an indicator of slip propensity. This study aimed to further develop slip prediction models based on RCOF by examining slips under moderately slippery conditions where the RCOF was approximately equal to the available coefficient of friction. Baseline RCOFs were found for normal walking trials and then an unexpected slip was introduced with a moderately slippery boot-floor contaminant combination for thirty-one subjects. Slip outcomes (i.e., whether a subject experienced a slip) were assessed based on the displacement of a marker placed on the heel. A logistic regression analysis was used to model the impact of RCOF on slipping. Results showed that subjects who walked with a greater RCOF were found to have a higher probability of slipping. The predicted probability of a slip across the RCOF ranged from 3% to 95% and an increase of 0.01 in RCOF was associated with a slipping odds ratio of 1.7. Thus, modest differences in RCOF can have a dramatic impact on slip propensity. This study shows that RCOF can be a sensitive and valid predictor of slipping in realistic frictional environments.
Source:Gait & Posture
Author(s): Kurt E. Beschorner, Devon L. Albert, Mark S. Redfern
The required coefficient of friction (RCOF) is frequently reported in the literature as an indicator of slip propensity. This study aimed to further develop slip prediction models based on RCOF by examining slips under moderately slippery conditions where the RCOF was approximately equal to the available coefficient of friction. Baseline RCOFs were found for normal walking trials and then an unexpected slip was introduced with a moderately slippery boot-floor contaminant combination for thirty-one subjects. Slip outcomes (i.e., whether a subject experienced a slip) were assessed based on the displacement of a marker placed on the heel. A logistic regression analysis was used to model the impact of RCOF on slipping. Results showed that subjects who walked with a greater RCOF were found to have a higher probability of slipping. The predicted probability of a slip across the RCOF ranged from 3% to 95% and an increase of 0.01 in RCOF was associated with a slipping odds ratio of 1.7. Thus, modest differences in RCOF can have a dramatic impact on slip propensity. This study shows that RCOF can be a sensitive and valid predictor of slipping in realistic frictional environments.
Tags: Hearing and Balance
Audiology and neurotology
Audiological Monitoring in Children Treated with Platinum Chemotherapy
Friday, June 10, 2016, 16:31
Platinum compounds constitute the standard treatment for solid tumors in pediatric oncology. The purpose of this study is to assess the impact of platinum compounds in the development of ototoxicity in children following chemotherapy. This study included 160 patients treated with cisplatin and carboplatin for malignant solid diseases from 2007 to 2014. Their audiograms were classified according to the Boston SIOP ototoxicity scale. Twenty-five percent of the children treated with platinum compounds developed ototoxicity. The incidence of ototoxicity was correlated with the type of platinum derivative (i.e. cisplatin vs. carboplatin), coadministration of both drugs and concomitant cranial radiotherapy, but not with sex and age. Cumulative dose was correlated only with the cisplatin administration. Nine patients (8.6%) showed further progression of hearing impairment after the end of chemotherapy. The low rate of ototoxicity suggests the pivotal role of auditory monitoring in children treated with platinum compounds in order to be able to identify hearing loss at an early stage and to provide, jointly with pediatric oncologists, strategies to reduce further progression of cochlear toxicity.
Audiol Neurotol 2016;21:203-211
Audiol Neurotol 2016;21:203-211
Tags: Hearing and Balance
Gait & Posture
The effect of viewing a virtual environment through a head-mounted display on balance
Friday, June 10, 2016, 15:17
Publication date: Available online 10 June 2016
Source:Gait & Posture
Author(s): Maxime T. Robert, Laurent Ballaz, Martin Lemay
Introduction In the next few years, several head-mounted displays (HMD) will be publicly released making virtual reality more accessible. HMD are expected to be widely popular at home for gaming but also in clinical settings, notably for training and rehabilitation. HMD can be used in both seated and standing positions; however, presently, the impact of HMD on balance remains largely unknown. It is therefore crucial to examine the impact of viewing a virtual environment through a HMD on standing balance. Objectives To compare static and dynamic balance in a virtual environment perceived through a HMD and the physical environment. The visual representation of the virtual environment was based on filmed image of the physical environment and was therefore highly similar. Design This is an observational study in healthy adults. Results No significant difference was observed between the two environments for static balance. However, dynamic balance was more perturbed in the virtual environment when compared to that of the physical environment. Conclusions HMD should be used with caution because of its detrimental impact on dynamic balance. Sensorimotor conflict possibly explains the impact of HMD on balance.
Source:Gait & Posture
Author(s): Maxime T. Robert, Laurent Ballaz, Martin Lemay
Introduction In the next few years, several head-mounted displays (HMD) will be publicly released making virtual reality more accessible. HMD are expected to be widely popular at home for gaming but also in clinical settings, notably for training and rehabilitation. HMD can be used in both seated and standing positions; however, presently, the impact of HMD on balance remains largely unknown. It is therefore crucial to examine the impact of viewing a virtual environment through a HMD on standing balance. Objectives To compare static and dynamic balance in a virtual environment perceived through a HMD and the physical environment. The visual representation of the virtual environment was based on filmed image of the physical environment and was therefore highly similar. Design This is an observational study in healthy adults. Results No significant difference was observed between the two environments for static balance. However, dynamic balance was more perturbed in the virtual environment when compared to that of the physical environment. Conclusions HMD should be used with caution because of its detrimental impact on dynamic balance. Sensorimotor conflict possibly explains the impact of HMD on balance.
Tags: Hearing and Balance
Gait & Posture
In vivo kinematic study of the tarsal joints complex based on fluoroscopic 3D-2D registration technique
Friday, June 10, 2016, 15:17
Publication date: Available online 10 June 2016
Source:Gait & Posture
Author(s): M.D. Chen Wang, Xiang Geng, Shaobai Wang, M.D. Xin Ma, M.D. Xu Wang, M.D. Jiazhang Huang, M.D. Chao Zhang, M.S. Li Chen, Junsheng Yang, Kan Wang
The tarsal bones articulate with each other and demonstrate complicated kinematic characteristics. The in vivo motions of these tarsal joints during normal gait are still unclear. Seven healthy subjects were recruited and fourteen feet in total were tested in current study. Three dimensional models of the tarsal bones were first created using CT scanning. Corresponding local 3D coordinate systems of each tarsal bone was subsequently established for 6DOF motion decompositions. The fluoroscopy system captured the lateral fluoroscopic images of the targeted tarsal region whilst the subject was walking. Seven key pose images during the stance phase were selected and 3D to 2D bone model registrations were performed on each image to determine joint positions. The 6DOF motions of each tarsal joint during gait were then obtained by connecting these positions together. The TNJ (talo-navicular joint) exhibited the largest ROMs (range of motion) on all rotational directions with 7.39±2.75°of dorsi/plantarflexion, 21.12±4.68°of inversion/eversion, and 16.11±4.44°of internal/external rotation. From heel strike to midstance, the TNJ, STJ (subtalar joint), and CCJ (calcaneao-cuboid joint) were associated with 5.97°, 5.04°, and 3.93°of dorsiflexion; 15.46°, 8.21°, and 5.82°of eversion; and 9.75°, 7.6°, and 4.99°of external rotation, respectively. Likewise, from midstance to heel off, the TNJ, STJ, and CCJ were associated with 6.39, 6.19°, and 4.47°of plantarflexion; 18.57°, 11.86°, and 6.32°of inversion and 13.95°, 9.66°, and 7.58°of internal rotation, respectively. In conclusion, among the tarsal joints, the TNJ exhibited the greatest rotational mobility. Synchronous and homodromous rotational motions were detected for TNJ, STJ, and CCJ during the stance phase.
Source:Gait & Posture
Author(s): M.D. Chen Wang, Xiang Geng, Shaobai Wang, M.D. Xin Ma, M.D. Xu Wang, M.D. Jiazhang Huang, M.D. Chao Zhang, M.S. Li Chen, Junsheng Yang, Kan Wang
The tarsal bones articulate with each other and demonstrate complicated kinematic characteristics. The in vivo motions of these tarsal joints during normal gait are still unclear. Seven healthy subjects were recruited and fourteen feet in total were tested in current study. Three dimensional models of the tarsal bones were first created using CT scanning. Corresponding local 3D coordinate systems of each tarsal bone was subsequently established for 6DOF motion decompositions. The fluoroscopy system captured the lateral fluoroscopic images of the targeted tarsal region whilst the subject was walking. Seven key pose images during the stance phase were selected and 3D to 2D bone model registrations were performed on each image to determine joint positions. The 6DOF motions of each tarsal joint during gait were then obtained by connecting these positions together. The TNJ (talo-navicular joint) exhibited the largest ROMs (range of motion) on all rotational directions with 7.39±2.75°of dorsi/plantarflexion, 21.12±4.68°of inversion/eversion, and 16.11±4.44°of internal/external rotation. From heel strike to midstance, the TNJ, STJ (subtalar joint), and CCJ (calcaneao-cuboid joint) were associated with 5.97°, 5.04°, and 3.93°of dorsiflexion; 15.46°, 8.21°, and 5.82°of eversion; and 9.75°, 7.6°, and 4.99°of external rotation, respectively. Likewise, from midstance to heel off, the TNJ, STJ, and CCJ were associated with 6.39, 6.19°, and 4.47°of plantarflexion; 18.57°, 11.86°, and 6.32°of inversion and 13.95°, 9.66°, and 7.58°of internal rotation, respectively. In conclusion, among the tarsal joints, the TNJ exhibited the greatest rotational mobility. Synchronous and homodromous rotational motions were detected for TNJ, STJ, and CCJ during the stance phase.
Tags: Hearing and Balance
Hearing Research
Neural correlates of auditory scale illusion
Friday, June 10, 2016, 11:20
Publication date: Available online 9 June 2016
Source:Hearing Research
Author(s): Shinya Kuriki, Ryousuke Numao, Iku Nemoto
The auditory illusory perception "scale illusion" occurs when ascending and descending musical scale tones are delivered in a dichotic manner, such that the higher or lower tone at each instant is presented alternately to the right and left ears. Resulting tone sequences have a zigzag pitch in one ear and the reversed (zagzig) pitch in the other ear. Most listeners hear illusory smooth pitch sequences of up-down and down-up streams in the two ears separated in higher and lower halves of the scale. Although many behavioral studies have been conducted, how and where in the brain the illusory percept is formed have not been elucidated. In this study, we conducted functional magnetic resonance imaging using sequential tones that induced scale illusion (ILL) and those that mimicked the percept of scale illusion (PCP), and we compared the activation responses evoked by those stimuli by region-of-interest analysis. We examined the effects of adaptation, i.e., the attenuation of response that occurs when close-frequency sounds are repeated, which might interfere with the changes in activation by the illusion process. Results of the activation difference of the two stimuli, measured at varied tempi of tone presentation, in the superior temporal auditory cortex were not explained by adaptation. Instead, excess activation of the ILL stimulus from the PCP stimulus at moderate tempi (83 and 126 bpm) was significant in the posterior auditory cortex with rightward superiority, while significant prefrontal activation was dominant at the highest tempo (245 bpm). We suggest that the area of the planum temporale posterior to the primary auditory cortex is mainly involved in the illusion formation, and that the illusion-related process is strongly dependent on the rate of tone presentation.
Source:Hearing Research
Author(s): Shinya Kuriki, Ryousuke Numao, Iku Nemoto
The auditory illusory perception "scale illusion" occurs when ascending and descending musical scale tones are delivered in a dichotic manner, such that the higher or lower tone at each instant is presented alternately to the right and left ears. Resulting tone sequences have a zigzag pitch in one ear and the reversed (zagzig) pitch in the other ear. Most listeners hear illusory smooth pitch sequences of up-down and down-up streams in the two ears separated in higher and lower halves of the scale. Although many behavioral studies have been conducted, how and where in the brain the illusory percept is formed have not been elucidated. In this study, we conducted functional magnetic resonance imaging using sequential tones that induced scale illusion (ILL) and those that mimicked the percept of scale illusion (PCP), and we compared the activation responses evoked by those stimuli by region-of-interest analysis. We examined the effects of adaptation, i.e., the attenuation of response that occurs when close-frequency sounds are repeated, which might interfere with the changes in activation by the illusion process. Results of the activation difference of the two stimuli, measured at varied tempi of tone presentation, in the superior temporal auditory cortex were not explained by adaptation. Instead, excess activation of the ILL stimulus from the PCP stimulus at moderate tempi (83 and 126 bpm) was significant in the posterior auditory cortex with rightward superiority, while significant prefrontal activation was dominant at the highest tempo (245 bpm). We suggest that the area of the planum temporale posterior to the primary auditory cortex is mainly involved in the illusion formation, and that the illusion-related process is strongly dependent on the rate of tone presentation.
Tags: Hearing and Balance
Hearing Research
Species-dependent role of crossmodal connectivity among the primary sensory cortices
Friday, June 10, 2016, 11:20
Publication date: Available online 9 June 2016
Source:Hearing Research
Author(s): M. Alex Meredith, Stephen G. Lomber
When a major sense is lost, crossmodal plasticity substitutes functional processing from the remaining, intact senses. Recent studies of deafness-induced crossmodal plasticity in different subregions of auditory cortex indicate that the phenomenon is largely based on the "unmasking" of existing inputs. However, there is not yet a consensus on the sources or effects of crossmodal inputs to primary sensory cortical areas. In the present review, a rigorous re-examination of the experimental literature indicates that connections between different primary sensory cortices consistently occur in rodents, while primary-to-primary projections are absent/inconsistent in non-rodents such as cats and monkeys. These observations suggest that crossmodal plasticity that involves primary sensory areas are likely to exhibit species-specific distinctions.
Source:Hearing Research
Author(s): M. Alex Meredith, Stephen G. Lomber
When a major sense is lost, crossmodal plasticity substitutes functional processing from the remaining, intact senses. Recent studies of deafness-induced crossmodal plasticity in different subregions of auditory cortex indicate that the phenomenon is largely based on the "unmasking" of existing inputs. However, there is not yet a consensus on the sources or effects of crossmodal inputs to primary sensory cortical areas. In the present review, a rigorous re-examination of the experimental literature indicates that connections between different primary sensory cortices consistently occur in rodents, while primary-to-primary projections are absent/inconsistent in non-rodents such as cats and monkeys. These observations suggest that crossmodal plasticity that involves primary sensory areas are likely to exhibit species-specific distinctions.
Graphical abstract
Tags: Hearing and Balance
The Journal of the Acoustical Society of America: Most Recent Articles
Optimal design of a hysteretic vibration absorber using fixed-points theory
Wai On Wong · Friday, June 10, 2016, 7:16
H ∞ optimum parameters of a dynamic vibration absorber (DVA) using a hysteretic or structural damping element have been derived analytically for suppressing vibration of a single degree-of-freedom (SDOF) system excited by harmonic forces or due to ground motions. Although the frequency response function of the traditional DVA (TDVA) withviscous damping may be converted to that of the hysteretic DVA (HDVA) using the equivalent viscous damping coefficient, it is found that the two frequency response functions are not equivalent after the optimization process. Therefore, the optimum parameters of the HDVA are derived using the fixed-points theory rather than converted directly from the TDVA model. The analytical results show that the optimized hysteretic vibration absorber can provide a similar vibration reduction effect as the optimized traditional dynamic vibration absorber at the resonance of a SDOF primary vibrating system. Advantages as well as the limitations of the fixed-points theory for the H ∞optimization of the hysteretic dynamic vibration absorbers using the fixed-points theory are discussed.
Tags: Hearing and Balance
The Journal of the Acoustical Society of America: Most Recent Articles
The influence of native-language tones on lexical access in the second language
Anthony Shook And Viorica Marian · Friday, June 10, 2016, 7:16
When listening to speech in a second language, bilinguals' perception of acoustic-phonetic properties is often influenced by the features that are important in the native language of the bilingual. Furthermore, changes in the perception of segmental contrasts due to L1 experience can influence L2 lexical access during comprehension. The present study investigates whether the effect of L1 experience on L2 processing seen at the segmental level extends to suprasegmental processing. In an eye-tracking task, Mandarin–English bilinguals heard an auditorily presented English word and selected which of two visually presented Chinese characters represented the correct Mandarin translation. The pitch contour of the spoken word was manipulated to either match or mismatch the lexical tone of the Mandarin translation. Results revealed that bilinguals were significantly faster to correctly identify the target and made earlier eyemovements to targets when the suprasegmental information of the word spoken in English matched that of its Mandarin translation. The findings provide compelling evidence for bilinguals' sensitivity to suprasegmental tone information, even when listening to a non-tonal language. These results have important implications for the effect of L1 experience on L2 lexical access and language interaction in bilinguals, and are consistent with a highly interactive account of language processing.
Tags: Hearing and Balance
The Journal of the Acoustical Society of America: Most Recent Articles
Auditory sensitivity in aquatic animalsa)
Klaus Lucke, Arthur N. Popper, Anthony D. Hawkins, Tomonari Akamatsu, Michel André, Brian K. Branstetter, Marc Lammers, Craig A. Radford, Amanda L. Stansbury And T. Aran Mooney · Friday, June 10, 2016, 7:16
A critical concern with respect to marine animal acoustics is the issue of hearing"sensitivity," as it is widely used as a criterion for the onset of noise-induced effects.Important aspects of research on sensitivity to sound by marine animals include: uncertainties regarding how well these species detect and respond to different sounds;the masking effects of man-made sounds on the detection of biologically importantsounds; the question how internal state, motivation, context, and previous experience affect their behavioral responses; and the long-term and cumulative effects of soundexposure. If we are to better understand the sensitivity of marine animals to sound we must concentrate research on these questions. In order to assess population level and ecological community impacts new approaches can possibly be adopted from other disciplines and applied to marine fauna.
Tags: Hearing and Balance
The Journal of the Acoustical Society of America: Most Recent Articles
Comparing the effects of age on amplitude modulation and frequency modulation detection
Nicolas Wallaert, Brian C. J. Moore And Christian Lorenzi · Friday, June 10, 2016, 7:16
Frequency modulation (FM) and amplitude modulation (AM) detection thresholds were measured at 40 dB sensation level for young (22–28 yrs) and older (44–66 yrs) listeners with normal audiograms for a carrier frequency of 500 Hz and modulation rates of 2 and 20 Hz. The number of modulation cycles, N, varied between 2 and 9. For FM detection,uninformative AM at the same rate as the FM was superimposed to disrupt excitation-pattern cues. For both groups, AM and FM detection thresholds were lower for the 2-Hz than for the 20-Hz rate, and AM and FM detection thresholds decreased with increasingN. Thresholds were higher for older than for younger listeners, especially for FMdetection at 2 Hz, possibly reflecting the effect of age on the use of temporal-fine-structure cues for 2-Hz FM detection. The effect of increasing N was similar across groups for both AM and FM. However, at 20 Hz, older listeners showed a greater effect of increasing N than younger listeners for both AM and FM. The results suggest that ageing reduces sensitivity to both excitation-pattern and temporal-fine-structure cues for modulation detection, but more so for the latter, while sparing temporal integration of these cues at low modulation rates.
Tags: Hearing and Balance
Audiology
Reducing Listening Effort via primax Hearing Technology
Thursday, June 09, 2016, 19:12
When listening situations become noisier or more challenging, this is even more important. However, beyond improving speech intelligibility, another indicator of the effectiveness of hearing aid fittings that has sometimes been overlooked is the cognitive demands, or listening effort required for speech understanding to take place. This is why it is important to not only improve speech understanding, but also make speech understanding easy. This is the underlying goal of the new Signia primax™ platform ― to improve speech intelligibility and reduce listening effort for the wearer.
Tags: Hearing and Balance
Hearing Research
Postnatal maturation of auditory-nerve response heterogeneity as seen in spatial gradients of synapse morphology in the inner hair cell area
Thursday, June 09, 2016, 11:17
Publication date: Available online 8 June 2016
Source:Hearing Research
Author(s): Leslie D. Liberman, M. Charles Liberman
Auditory nerve fibers in the adult ear are divided into functional subgroups according to spontaneous rate (SR) and threshold sensitivity. The high-threshold, low-SR fibers are morphologically and spatially distinct from the low-threshold high-SR fibers at their synaptic contacts with inner hair cells. This distinction between SR groups in the adult ear is visible in confocal microscopy as complementary size gradients of presynaptic ribbons and post-synaptic glutamate receptor patches across the modiolar-pillar and habenular-cuticular axes in the inner hair cell area. The aim of the present study was to track the post-natal development of this morphological gradient, in mouse, to determine the earliest age at which this important aspect of cochlear organization is fully mature. Here we show, using morphometric analysis of the organ of Corti immunostained for pre- and post-synaptic markers of efferent and afferent innervation, that this SR-based morphological gradient is not fully established until postnatal day 28, well after other features, such as synaptic counts and efferent innervation density in both the inner and outer hair cell areas, appear fully mature.
Source:Hearing Research
Author(s): Leslie D. Liberman, M. Charles Liberman
Auditory nerve fibers in the adult ear are divided into functional subgroups according to spontaneous rate (SR) and threshold sensitivity. The high-threshold, low-SR fibers are morphologically and spatially distinct from the low-threshold high-SR fibers at their synaptic contacts with inner hair cells. This distinction between SR groups in the adult ear is visible in confocal microscopy as complementary size gradients of presynaptic ribbons and post-synaptic glutamate receptor patches across the modiolar-pillar and habenular-cuticular axes in the inner hair cell area. The aim of the present study was to track the post-natal development of this morphological gradient, in mouse, to determine the earliest age at which this important aspect of cochlear organization is fully mature. Here we show, using morphometric analysis of the organ of Corti immunostained for pre- and post-synaptic markers of efferent and afferent innervation, that this SR-based morphological gradient is not fully established until postnatal day 28, well after other features, such as synaptic counts and efferent innervation density in both the inner and outer hair cell areas, appear fully mature.
Tags: Hearing and Balance
The Journal of the Acoustical Society of America
Optimal design of a hysteretic vibration absorber using fixed-points theory
Wai On Wong · Wednesday, June 08, 2016, 23:43
H ∞ optimum parameters of a dynamic vibration absorber (DVA) using a hysteretic or structural damping element have been derived analytically for suppressing vibration of a single degree-of-freedom (SDOF) system excited by harmonic forces or due to ground motions. Although the frequency response function of the traditional DVA (TDVA) withviscous damping may be converted to that of the hysteretic DVA (HDVA) using the equivalent viscous damping coefficient, it is found that the two frequency response functions are not equivalent after the optimization process. Therefore, the optimum parameters of the HDVA are derived using the fixed-points theory rather than converted directly from the TDVA model. The analytical results show that the optimized hysteretic vibration absorber can provide a similar vibration reduction effect as the optimized traditional dynamic vibration absorber at the resonance of a SDOF primary vibrating system. Advantages as well as the limitations of the fixed-points theory for the H ∞optimization of the hysteretic dynamic vibration absorbers using the fixed-points theory are discussed.
Tags: Hearing and Balance
The Journal of the Acoustical Society of America
The influence of native-language tones on lexical access in the second language
Anthony Shook And Viorica Marian · Wednesday, June 08, 2016, 23:43
When listening to speech in a second language, bilinguals' perception of acoustic-phonetic properties is often influenced by the features that are important in the native language of the bilingual. Furthermore, changes in the perception of segmental contrasts due to L1 experience can influence L2 lexical access during comprehension. The present study investigates whether the effect of L1 experience on L2 processing seen at the segmental level extends to suprasegmental processing. In an eye-tracking task, Mandarin–English bilinguals heard an auditorily presented English word and selected which of two visually presented Chinese characters represented the correct Mandarin translation. The pitch contour of the spoken word was manipulated to either match or mismatch the lexical tone of the Mandarin translation. Results revealed that bilinguals were significantly faster to correctly identify the target and made earlier eyemovements to targets when the suprasegmental information of the word spoken in English matched that of its Mandarin translation. The findings provide compelling evidence for bilinguals' sensitivity to suprasegmental tone information, even when listening to a non-tonal language. These results have important implications for the effect of L1 experience on L2 lexical access and language interaction in bilinguals, and are consistent with a highly interactive account of language processing.
Tags: Hearing and Balance
The Journal of the Acoustical Society of America
Auditory sensitivity in aquatic animalsa)
Klaus Lucke, Arthur N. Popper, Anthony D. Hawkins, Tomonari Akamatsu, Michel André, Brian K. Branstetter, Marc Lammers, Craig A. Radford, Amanda L. Stansbury And T. Aran Mooney · Wednesday, June 08, 2016, 23:43
A critical concern with respect to marine animal acoustics is the issue of hearing"sensitivity," as it is widely used as a criterion for the onset of noise-induced effects.Important aspects of research on sensitivity to sound by marine animals include: uncertainties regarding how well these species detect and respond to different sounds;the masking effects of man-made sounds on the detection of biologically importantsounds; the question how internal state, motivation, context, and previous experience affect their behavioral responses; and the long-term and cumulative effects of soundexposure. If we are to better understand the sensitivity of marine animals to sound we must concentrate research on these questions. In order to assess population level and ecological community impacts new approaches can possibly be adopted from other disciplines and applied to marine fauna.
Tags: Hearing and Balance
The Journal of the Acoustical Society of America
Comparing the effects of age on amplitude modulation and frequency modulation detection
Nicolas Wallaert, Brian C. J. Moore And Christian Lorenzi · Wednesday, June 08, 2016, 23:43
Frequency modulation (FM) and amplitude modulation (AM) detection thresholds were measured at 40 dB sensation level for young (22–28 yrs) and older (44–66 yrs) listeners with normal audiograms for a carrier frequency of 500 Hz and modulation rates of 2 and 20 Hz. The number of modulation cycles, N, varied between 2 and 9. For FM detection,uninformative AM at the same rate as the FM was superimposed to disrupt excitation-pattern cues. For both groups, AM and FM detection thresholds were lower for the 2-Hz than for the 20-Hz rate, and AM and FM detection thresholds decreased with increasingN. Thresholds were higher for older than for younger listeners, especially for FMdetection at 2 Hz, possibly reflecting the effect of age on the use of temporal-fine-structure cues for 2-Hz FM detection. The effect of increasing N was similar across groups for both AM and FM. However, at 20 Hz, older listeners showed a greater effect of increasing N than younger listeners for both AM and FM. The results suggest that ageing reduces sensitivity to both excitation-pattern and temporal-fine-structure cues for modulation detection, but more so for the latter, while sparing temporal integration of these cues at low modulation rates.
Tags: Hearing and Balance
Gait & Posture
Relationship between trunk and foot accelerations during walking in healthy adults
Wednesday, June 08, 2016, 23:13
Publication date: Available online 8 June 2016
Source:Gait & Posture
Author(s): Jordan J. Craig, Adam Bruetsch, Jessie M. Huisinga
Source:Gait & Posture
Author(s): Jordan J. Craig, Adam Bruetsch, Jessie M. Huisinga
Tags: Hearing and Balance
Gait & Posture
Variability of gait speed during six minutes walking test in COPD and cystic fibrosis patients
Wednesday, June 08, 2016, 23:13
Publication date: Available online 8 June 2016
Source:Gait & Posture
Author(s): Gregory Reychler, Margaux Debatisse, Patrick Lebecque, Thierry Pieters, Giuseppe Liistro, Sophie Gohy
Background Recently, gait speed reached an increasing importance in the management of respiratory patients. The aim of this retrospective study was to compare walking speed and physiological adaptations during the 6MWT in COPD and CF patients. Methods 6MWT performed by COPD and CF patients were retrospectively reviewed. Global and sequential walking speeds were measured on six minutes and every sequence of two minutes respectively. Heart rate, oxygen saturation and dyspnea were analyzed. Results 78 and 246 tests from CF and COPD patients were reviewed respectively. FEV1 (52.3 vs 56.2% pred) and FVC (72.5 vs 73.8% pred) were similar between both diseases. However, 6MWT in patients with CF were characterized by significantly higher heart rate, global walking speed and walking distance (+68%) while dyspnea evolutions and the proportions of patients presenting walking speed decline over the 6minutes were significantly lower. Conclusion Walking speed and cardio-respiratory parameters evolution during 6MWT differ between COPD and CF patients.
Source:Gait & Posture
Author(s): Gregory Reychler, Margaux Debatisse, Patrick Lebecque, Thierry Pieters, Giuseppe Liistro, Sophie Gohy
Background Recently, gait speed reached an increasing importance in the management of respiratory patients. The aim of this retrospective study was to compare walking speed and physiological adaptations during the 6MWT in COPD and CF patients. Methods 6MWT performed by COPD and CF patients were retrospectively reviewed. Global and sequential walking speeds were measured on six minutes and every sequence of two minutes respectively. Heart rate, oxygen saturation and dyspnea were analyzed. Results 78 and 246 tests from CF and COPD patients were reviewed respectively. FEV1 (52.3 vs 56.2% pred) and FVC (72.5 vs 73.8% pred) were similar between both diseases. However, 6MWT in patients with CF were characterized by significantly higher heart rate, global walking speed and walking distance (+68%) while dyspnea evolutions and the proportions of patients presenting walking speed decline over the 6minutes were significantly lower. Conclusion Walking speed and cardio-respiratory parameters evolution during 6MWT differ between COPD and CF patients.
Tags: Hearing and Balance
Gait & Posture
A new method to calculate external mechanical work using force-platform data in ecological situations in humans: application to Parkinson's disease
Wednesday, June 08, 2016, 23:13
Publication date: Available online 7 June 2016
Source:Gait & Posture
Author(s): Vincent Gigot, Virginie Van Wymelbeke, Davy Laroche, Thomas Mouillot, Agnès Jacquin-Piques, Matthieu Rossé, Michel Tavan, Laurent Brondel
Background and aim To accurately quantify the cost of physical activity and to evaluate the different components of energy expenditure in humans, it is necessary to evaluate external mechanical work (WEXT). Large platform systems surpass other currently used techniques. Here, we describe a calculation method for force-platforms to calculate long-term WEXT. Methods Each force-platform (2.46 x 1.60 m and 3.80 x 2.48 m) rests on 4 piezoelectric sensors. During long periods of recording, a drift in the speed of displacement of the center of mass (necessary to calculate WEXT) is generated. To suppress this drift, wavelet decomposition is used to low-pass filter the source signal. By using wavelet decomposition coefficients, the source signal can be recovered. To check the validity of WEXT calculations after signal processing, an oscillating pendulum system was first used; then, 10 healthy subjects performed a standardized exercise (squatting exercise). A medical application is also reported in eight Parkinsonian patients during the timed "get-up and go" test and compared with the same test in ten healthy subjects. Results Values of WEXT with the oscillating pendulum showed that the system was accurate and reliable. During the squatting exercise, the average measured WEXT was 0.4% lower than theoretical work. WEXT and mechanical work efficiency during the "get-up and go" test in Parkinson's disease patients in comparison with that of healthy subjects were very coherent. Conclusions This method has numerous applications for studying physical activity and mechanical work efficiency in physiological and pathological conditions.
Source:Gait & Posture
Author(s): Vincent Gigot, Virginie Van Wymelbeke, Davy Laroche, Thomas Mouillot, Agnès Jacquin-Piques, Matthieu Rossé, Michel Tavan, Laurent Brondel
Background and aim To accurately quantify the cost of physical activity and to evaluate the different components of energy expenditure in humans, it is necessary to evaluate external mechanical work (WEXT). Large platform systems surpass other currently used techniques. Here, we describe a calculation method for force-platforms to calculate long-term WEXT. Methods Each force-platform (2.46 x 1.60 m and 3.80 x 2.48 m) rests on 4 piezoelectric sensors. During long periods of recording, a drift in the speed of displacement of the center of mass (necessary to calculate WEXT) is generated. To suppress this drift, wavelet decomposition is used to low-pass filter the source signal. By using wavelet decomposition coefficients, the source signal can be recovered. To check the validity of WEXT calculations after signal processing, an oscillating pendulum system was first used; then, 10 healthy subjects performed a standardized exercise (squatting exercise). A medical application is also reported in eight Parkinsonian patients during the timed "get-up and go" test and compared with the same test in ten healthy subjects. Results Values of WEXT with the oscillating pendulum showed that the system was accurate and reliable. During the squatting exercise, the average measured WEXT was 0.4% lower than theoretical work. WEXT and mechanical work efficiency during the "get-up and go" test in Parkinson's disease patients in comparison with that of healthy subjects were very coherent. Conclusions This method has numerous applications for studying physical activity and mechanical work efficiency in physiological and pathological conditions.
Tags: Hearing and Balance
Gait & Posture
Sit-to-Walk and Sit-to-Stand-and-Walk Task Dynamics are Maintained during Rising at an Elevated Seat-Height Independent of Lead-Limb in Healthy Individuals
Tuesday, June 07, 2016, 23:13
Publication date: Available online 7 June 2016
Source:Gait & Posture
Author(s): Gareth D. Jones, Darren C. James, Michael Thacker, Eleanor J. Jones, David A. Green
Introduction Sit-to-walk (STW) is a common transitional motor task not usually included in rehabilitation. Typically, sit-to-stand (STS), pause, then gait initiation (GI) before walking is used, which we term sit-to-stand-and-walk (STSW). Separation between centre-of-pressure (COP) and whole-body centre-of-mass (BCOM) during GI is associated with dynamic postural stability. Rising from seats higher than knee-height (KH) is more achievable for patients, but whether this and/or lead-limb significantly affects task dynamics is unclear. This study tested whether rising from seat-heights and lead-limb affects STW and STSW task dynamics in young healthy individuals. Methods Ten (5F) young (29±7.7 years) participants performed STW and STSW from a standardised position. Five trials of each task were completed at 100 and 120%KH leading with dominant and non-dominant legs. Four force-plates and optical motion capture delineated key movement events and phases with effect of seat-height and lead-limb determined by 2-way ANOVA within tasks. Results At 120%KH, lower peak vertical ground-reaction-forces (vGRFs) and vertical BCOM velocities were observed during rising irrespective of lead-limb. No other parameters differed between seat-heights or lead-limbs. During GI in STSW there was more lateral, and less posterior, COP excursion than expected. Conclusion Reduction in vGRFs and velocity during rising at 120%KH is consistent with reduced effort in young healthy individuals and is likely therefore to be an appropriate seat-height for patients. Lead-limb had no effect upon STSW or STW parameters suggesting that normative data independent of lead-limb can be utilised to monitor motor rehabilitation should differences be observed in patients. STSW should be considered an independent movement transition.
Source:Gait & Posture
Author(s): Gareth D. Jones, Darren C. James, Michael Thacker, Eleanor J. Jones, David A. Green
Introduction Sit-to-walk (STW) is a common transitional motor task not usually included in rehabilitation. Typically, sit-to-stand (STS), pause, then gait initiation (GI) before walking is used, which we term sit-to-stand-and-walk (STSW). Separation between centre-of-pressure (COP) and whole-body centre-of-mass (BCOM) during GI is associated with dynamic postural stability. Rising from seats higher than knee-height (KH) is more achievable for patients, but whether this and/or lead-limb significantly affects task dynamics is unclear. This study tested whether rising from seat-heights and lead-limb affects STW and STSW task dynamics in young healthy individuals. Methods Ten (5F) young (29±7.7 years) participants performed STW and STSW from a standardised position. Five trials of each task were completed at 100 and 120%KH leading with dominant and non-dominant legs. Four force-plates and optical motion capture delineated key movement events and phases with effect of seat-height and lead-limb determined by 2-way ANOVA within tasks. Results At 120%KH, lower peak vertical ground-reaction-forces (vGRFs) and vertical BCOM velocities were observed during rising irrespective of lead-limb. No other parameters differed between seat-heights or lead-limbs. During GI in STSW there was more lateral, and less posterior, COP excursion than expected. Conclusion Reduction in vGRFs and velocity during rising at 120%KH is consistent with reduced effort in young healthy individuals and is likely therefore to be an appropriate seat-height for patients. Lead-limb had no effect upon STSW or STW parameters suggesting that normative data independent of lead-limb can be utilised to monitor motor rehabilitation should differences be observed in patients. STSW should be considered an independent movement transition.
Tags: Hearing and Balance
from #Med Blogs by Alexandros G.Sfakianakis via Alexandros G.Sfakianakis on Inoreader http://ift.tt/1Xn2IyM
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from #Med Blogs by Alexandros G.Sfakianakis via Alexandros G.Sfakianakis on Inoreader http://ift.tt/25ZUbDQ
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