Investigation of the relationship between cochlear gain reduction and speech-in-noise performance at positive and negative signal-to-noise ratios

The signal-to-noise ratio advantage of a directional microphone is achieved by reducing the sensitivity of the microphone to sounds from the sides and back. A fully adaptive directional microphone (one that automatically switches between an omnidirectional mode and various directional polar patterns) may allow the achievement of signal-to-noise (SNR) improvement with minimal loss on audibility to sounds that originate from the sides and back. To demonstrate such possibilities, this study compared the soundfield aided thresholds, speech in quiet at different input levels, and speech in noise performance of 17 hearing-impaired participants under three microphone modes (omnidirectional, fixed hypercardioid, and fully [or automatic] adaptive) as the stimuli were presented from 0° to 180° in 45° intervals. The results showed a significant azimuth effect only with the fixed directional microphone. In quiet, the fully adaptive microphone performed similarly as the omnidirectional microphone at all frequencies, input levels, and azimuths. In noise, the fully adaptive microphone achieved similar SNR improvement as the fixed directional microphone. Clinical implications of the results of this study were discussed.

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The Relationship Between Self-Perceived Hearing Ability and Binaural Speech-in-Noise Performance in Adults With Normal Pure-Tone Hearing

Perspectives of the ASHA Special Interest Groups ◽

10.1044/2021_persp-21-00032 ◽

2021 ◽

pp. 1-12

Author(s):

Christina M. Roup ◽

Amy Custer ◽

Julie Powell

Keyword(s):

Pure Tone ◽

Subscale Score ◽

Auditory Memory ◽

Global Score ◽

Noise Performance ◽

Normal Range ◽

Speech In Noise ◽

Hearing Ability ◽

The Relationship ◽

Hearing Abilities

Purpose This study examined the relationship between self-perceived hearing abilities and binaural speech-in-noise performance in young to middle-age adults with normal pure-tone hearing. Method Sixty-six adults with normal hearing (thresholds ≤ 25 dB HL at 250–8000 Hz) participated. Self-perceived hearing abilities were assessed using the Adult Auditory Performance Scale (AAPS). The AAPS provides a single global score of self-perceived hearing abilities and individual subscale scores for six listening conditions, namely, Quiet, Ideal, Noise, Multiple Inputs, Auditory Memory, and Auditory Attention. Binaural speech-in-noise performance was measured with the Listening in Spatialized Noise–Sentences Test (LiSN-S). Results Results revealed significant correlations between the AAPS and the LiSN-S. Listeners who scored higher on the AAPS (greater self-perceived hearing difficulty) performed poorer on the LiSN-S. The strongest correlations were observed between the AAPS Noise subscale score and the LiSN-S low- and high-cue conditions. Age was significantly correlated with both pure-tone hearing and the LiSN-S spatial advantage, with older participants exhibiting poorer thresholds and smaller spatial advantages. Pure-tone hearing was also significantly correlated with binaural speech-in-noise performance. Listeners with poorer thresholds performed poorer across multiple LiSN-S conditions. Linear regression revealed that a significant amount of the variance in LiSN-S performance was accounted for by pure-tone hearing as well as the AAPS global score and Noise subscale score. Conclusions Results demonstrate a clear relationship between an individual's self-perceived hearing ability and their binaural speech-in-noise performance. In addition, minimal threshold elevation within the normal range and age (i.e., middle adulthood) had a negative impact on binaural speech-in-noise performance. The results support the inclusion of speech-in-noise testing for all patients, even those whose pure-tone hearing falls within the traditional normal range.

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Sustained envelope periodicity representations are associated with speech-in-noise performance in difficult listening conditions for younger and older adults

Journal of Neurophysiology ◽

10.1152/jn.00845.2018 ◽

2019 ◽

Vol 122 (4) ◽

pp. 1685-1696 ◽

Cited By ~ 1

Author(s):

Carolyn M. McClaskey ◽

James W. Dias ◽

Kelly C. Harris

Keyword(s):

Older Adults ◽

Modulation Depth ◽

Phase Locking ◽

Modulation Frequency ◽

Normal Hearing ◽

Spectral Amplitude ◽

Noise Performance ◽

Speech In Noise ◽

Envelope Processing ◽

The Relationship

Temporal modulations are an important part of speech signals. An accurate perception of these time-varying qualities of sound is necessary for successful communication. The current study investigates the relationship between sustained envelope encoding and speech-in-noise perception in a cohort of normal-hearing younger (ages 18–30 yr, n = 22) and older adults (ages 55–90+ yr, n = 35) using the subcortical auditory steady-state response (ASSR). ASSRs were measured in response to the envelope of 400-ms amplitude-modulated (AM) tones with 3,000-Hz carrier frequencies and 80-Hz modulation frequencies. AM tones had modulation depths of 0, −4, and −8 dB relative to m = 1 ( m = 1, 0.631, and 0.398, respectively). The robustness, strength at modulation frequency, and synchrony of subcortical envelope encoding were quantified via time-domain correlations, spectral amplitude, and phase-locking value, respectively. Speech-in-noise ability was quantified via the QuickSIN test in the 0- and 5-dB signal-to-noise (SNR) conditions. All ASSR metrics increased with increasing modulation depth and there were no effects of age group. ASSR metrics in response to shallow modulation depths predicted 0-dB speech scores. Results demonstrate that sustained amplitude envelope processing in the brainstem relates to speech-in-noise abilities, but primarily in difficult listening conditions at low SNRs. These findings furthermore highlight the utility of shallow modulation depths for studying temporal processing. The absence of age effects in these data demonstrate that individual differences in the robustness, strength, and specificity of subcortical envelope processing, and not age, predict speech-in-noise performance in the most difficult listening conditions. NEW & NOTEWORTHY Failure to correctly understand speech in the presence of background noise is a significant problem for many normal-hearing adults and may impede healthy communication. The relationship between sustained envelope encoding in the brainstem and speech-in-noise perception remains to be clarified. The present study demonstrates that the strength, specificity, and robustness of the brainstem’s representations of sustained stimulus periodicity relates to speech-in-noise perception in older and younger normal-hearing adults, but only in highly challenging listening environments.

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Radiation Damage, Contrast and Statistics in High Resolution Biological Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100068291 ◽

1970 ◽

Vol 28 ◽

pp. 260-261

Author(s):

Robert M. Glaeser

Keyword(s):

High Resolution ◽

Particle Flux ◽

Unit Area ◽

Signal To Noise ◽

Resolution Image ◽

High Resolution Image ◽

Pass Through ◽

Counting Statistics ◽

The Relationship ◽

Picture Element

It is well known that a large flux of electrons must pass through a specimen in order to obtain a high resolution image while a smaller particle flux is satisfactory for a low resolution image. The minimum particle flux that is required depends upon the contrast in the image and the signal-to-noise (S/N) ratio at which the data are considered acceptable. For a given S/N associated with statistical fluxtuations, the relationship between contrast and “counting statistics” is s131_eqn1, where C = contrast; r2 is the area of a picture element corresponding to the resolution, r; N is the number of electrons incident per unit area of the specimen; f is the fraction of electrons that contribute to formation of the image, relative to the total number of electrons incident upon the object.

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Grain separation enhanced magnetic coercivity in Pt/Co multilayers.

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100151027 ◽

1993 ◽

Vol 51 ◽

pp. 1038-1039 ◽

Cited By ~ 1

Author(s):

G.A. Bertero ◽

R. Sinclair

Keyword(s):

Remanent Magnetization ◽

Strong Influence ◽

Uniaxial Anisotropy ◽

Magnetic Coupling ◽

Recording Media ◽

Magnetic Media ◽

Signal To Noise ◽

Out Of Plane ◽

Longitudinal Recording ◽

The Relationship

Pt/Co multilayers displaying perpendicular (out-of-plane) magnetic anisotropy and 100% perpendicular remanent magnetization are strong candidates as magnetic media for the next generation of magneto-optic recording devices. The magnetic coercivity, Hc, and uniaxial anisotropy energy, Ku, are two important materials parameters, among others, in the quest to achieving higher recording densities with acceptable signal to noise ratios (SNR). The relationship between Ku and Hc in these films is not a simple one since features such as grain boundaries, for example, can have a strong influence on Hc but affect Ku only in a secondary manner. In this regard grain boundary separation provides a way to minimize the grain-to-grain magnetic coupling which is known to result in larger coercivities and improved SNR as has been discussed extensively in the literature for conventional longitudinal recording media.We present here results from the deposition of two Pt/Co/Tb multilayers (A and B) which show significant differences in their coercive fields.

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Developmental Links Between Speech Perception in Noise, Singing, and Cortical Processing of Music in Children with Cochlear Implants

Music Perception An Interdisciplinary Journal ◽

10.1525/mp.2018.36.2.156 ◽

2018 ◽

Vol 36 (2) ◽

pp. 156-174 ◽

Cited By ~ 9

Author(s):

Ritva Torppa ◽

Andrew Faulkner ◽

Teija Kujala ◽

Minna Huotilainen ◽

Jari Lipsanen

Keyword(s):

Speech Perception ◽

Cochlear Implants ◽

Musical Instrument ◽

Noise Performance ◽

Speech Perception In Noise ◽

Speech In Noise ◽

Brain Responses ◽

Time Period ◽

Musical Sounds ◽

Auditory Skills

The perception of speech in noise is challenging for children with cochlear implants (CIs). Singing and musical instrument playing have been associated with improved auditory skills in normal-hearing (NH) children. Therefore, we assessed how children with CIs who sing informally develop in the perception of speech in noise compared to those who do not. We also sought evidence of links of speech perception in noise with MMN and P3a brain responses to musical sounds and studied effects of age and changes over a 14–17 month time period in the speech-in-noise performance of children with CIs. Compared to the NH group, the entire CI group was less tolerant of noise in speech perception, but both groups improved similarly. The CI singing group showed better speech-in-noise perception than the CI non-singing group. The perception of speech in noise in children with CIs was associated with the amplitude of MMN to a change of sound from piano to cymbal, and in the CI singing group only, with earlier P3a for changes in timbre. While our results cannot address causality, they suggest that singing and musical instrument playing may have a potential to enhance the perception of speech in noise in children with CIs.

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Electro-haptic hearing: Speech-in-noise performance in cochlear implant users is enhanced by tactile stimulation of the wrists

10.31234/osf.io/j6bn4 ◽

2019 ◽

Author(s):

Mark D. Fletcher ◽

Amatullah Hadeedi ◽

Tobias Goehring ◽

Sean R Mills

Keyword(s):

Cochlear Implant ◽

Speech Intelligibility ◽

Tactile Stimulation ◽

Electrical Signal ◽

Noise Performance ◽

Speech In Noise ◽

Non Invasive ◽

Real World Application ◽

Before And After ◽

Stimulation Of

Cochlear implant (CI) users receive only limited sound information through their implant, which means that they struggle to understand speech in noisy environments. Recent work has suggested that combining the electrical signal from the CI with a haptic signal that provides crucial missing sound information (“electro-haptic stimulation”; EHS) could improve speech-in-noise performance. The aim of the current study was to test whether EHS could enhance speech-in-noise performance in CI users using: (1) a tactile signal derived using an algorithm that could be applied in real time, (2) a stimulation site appropriate for a real-world application, and (3) a tactile signal that could readily be produced by a compact, portable device. We measured speech intelligibility in multi-talker noise with and without vibro-tactile stimulation of the wrist in CI users, before and after a short training regime. No effect of EHS was found before training, but after training EHS was found to improve the number of words correctly identified by an average of 8.3 %-points, with some users improving by more than 20 %-points. Our approach could offer an inexpensive and non-invasive means of improving speech-in-noise performance in CI users.

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Effect of Carnatic Music Listening Training on Speech in Noise Performance in Adults

Journal of Audiology & Otology ◽

10.7874/jao.2020.00255 ◽

2021 ◽

Vol 25 (1) ◽

pp. 22-26

Author(s):

Raksha Amemane ◽

Archana Gundmi ◽

Kishan Madikeri Mohan

Keyword(s):

Repeated Measures ◽

Functional Organization ◽

Control Group ◽

Music Listening ◽

Noise Performance ◽

Short Term ◽

Speech In Noise ◽

Carnatic Music ◽

Significant Difference ◽

And Control

Background and Objectives: Music listening has a concomitant effect on structural and functional organization of the brain. It helps in relaxation, mind training and neural strengthening. In relation to it, the present study was aimed to find the effect of Carnatic music listening training (MLT) on speech in noise performance in adults.Subjects and Methods: A total of 28 participants (40-70 years) were recruited in the study. Based on randomized control trial, they were divided into intervention and control group. Intervention group underwent a short-term MLT. Quick Speech-in-Noise in Kannada was used as an outcome measure.Results: Results were analysed using mixed method analysis of variance (ANOVA) and repeated measures ANOVA. There was a significant difference between intervention and control group post MLT. The results of the second continuum revealed no statistically significant difference between post training and follow-up scores in both the groups.Conclusions: In conclusion short-term MLT resulted in betterment of speech in noise performance. MLT can be hence used as a viable tool in formal auditory training for better prognosis.

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Evaluation of Automatic Directional Processing with Cochlear Implant Recipients

Journal of the American Academy of Audiology ◽

10.1055/s-0041-1733967 ◽

2021 ◽

Vol 32 (08) ◽

pp. 478-486

Author(s):

Lisa G. Potts ◽

Soo Jang ◽

Cory L. Hillis

Keyword(s):

Signal Processing ◽

Speech Recognition ◽

Cochlear Implant ◽

Mixed Model ◽

Dynamic Range ◽

Individual Variability ◽

Noise Performance ◽

Mixed Model Analysis ◽

Speech In Noise ◽

Speech Recognition In Noise

Abstract Background For cochlear implant (CI) recipients, speech recognition in noise is consistently poorer compared with recognition in quiet. Directional processing improves performance in noise and can be automatically activated based on acoustic scene analysis. The use of adaptive directionality with CI recipients is new and has not been investigated thoroughly, especially utilizing the recipients' preferred everyday signal processing, dynamic range, and/or noise reduction. Purpose This study utilized CI recipients' preferred everyday signal processing to evaluate four directional microphone options in a noisy environment to determine which option provides the best speech recognition in noise. A greater understanding of automatic directionality could ultimately improve CI recipients' speech-in-noise performance and better guide clinicians in programming. Study Sample Twenty-six unilateral and seven bilateral CI recipients with a mean age of 66 years and approximately 4 years of CI experience were included. Data Collection and Analysis Speech-in-noise performance was measured using eight loudspeakers in a 360-degree array with HINT sentences presented in restaurant noise. Four directional options were evaluated (automatic [SCAN], adaptive [Beam], fixed [Zoom], and Omni-directional) with participants' everyday use signal processing options active. A mixed-model analysis of variance (ANOVA) and pairwise comparisons were performed. Results Automatic directionality (SCAN) resulted in the best speech-in-noise performance, although not significantly better than Beam. Omni-directional performance was significantly poorer compared with the three other directional options. A varied number of participants performed their best with each of the four-directional options, with 16 performing best with automatic directionality. The majority of participants did not perform best with their everyday directional option. Conclusion The individual variability seen in this study suggests that CI recipients try with different directional options to find their ideal program. However, based on a CI recipient's motivation to try different programs, automatic directionality is an appropriate everyday processing option.

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