Clinical features and prognostic factors of pediatric idiopathic sudden hearing loss from moderate to profound degree.

BACKGROUND: The pediatric idiopathic sudden sensorineural hearing loss (PISSNHL) is not rare in the clinics, however, the prognostic factors of PISSNHL are still unclear. OBJECTIVES: To investigate the clinical and audiologic characteristics associated with prognosis in PISSNHL. MATERIAL AND METHODS: Clinical and audiological characteristics and possible prognostic factors were retrospectively evaluated in 76 PISSNHL patients aged less than 19 years. RESULTS: Hearing loss was moderate in nine patients, severe in 21 patients, profound in 46 patients. Among five types of audiogram, 3.9% were classified as ascending, 11.8% as descending, 25.0% as flat, 55.3% as profound, and 3.9% as concave. The recovery rate according to Siegel's criteria was 55.3%. There was no significant difference between the recovery group and the poor recovery group in terms of age, sex, laterality of hearing loss, the onset of treatment, and accompanying symptoms (p > 0.05). The initial hearing levels and the audiogram type were significantly different in the two groups (p < 0.001) according to univariate analysis, while only the initial hearing level was significantly different (p = 0.046) according to multivariate analysis. CONCLUSIONS AND SIGNIFICANCE: Prognosis of PISSNHL was mainly related to initial hearing at onset. An initial hearing level greater than 80 dB was a poor prognostic factor.

Spectrally specific temporal analyses of spike-train responses to complex sounds: A unifying framework.

Significant scientific and translational questions remain in auditory neuroscience surrounding the neural correlates of perception. Relating perceptual and neural data collected from humans can be useful; however, human-based neural data are typically limited to evoked far-field responses, which lack anatomical and physiological specificity. Laboratory-controlled preclinical animal models offer the advantage of comparing single-unit and evoked responses from the same animals. This ability provides opportunities to develop invaluable insight into proper interpretations of evoked responses, which benefits both basic-science studies of neural mechanisms and translational applications, e.g., diagnostic development. However, these comparisons have been limited by a disconnect between the types of spectrotemporal analyses used with single-unit spike trains and evoked responses, which results because these response types are fundamentally different (point-process versus continuous-valued signals) even though the responses themselves are related. Here, we describe a unifying framework to study temporal coding of complex sounds that allows spike-train and evoked-response data to be analyzed and compared using the same advanced signal-processing techniques. The framework uses a set of peristimulus-time histograms computed from single-unit spike trains in response to polarity-alternating stimuli to allow advanced spectral analyses of both slow (envelope) and rapid (temporal fine structure) response components. Demonstrated benefits include: (1) novel spectrally specific temporal-coding measures that are less confounded by distortions due to hair-cell transduction, synaptic rectification, and neural stochasticity compared to previous metrics, e.g., the correlogram peak-height, (2) spectrally specific analyses of spike-train modulation coding (magnitude and phase), which can be directly compared to modern perceptually based models of speech intelligibility (e.g., that depend on modulation filter banks), and (3) superior spectral resolution in analyzing the neural representation of nonstationary sounds, such as speech and music. This unifying framework significantly expands the potential of preclinical animal models to advance our understanding of the physiological correlates of perceptual deficits in real-world listening following sensorineural hearing loss.

Clinical characteristics and correlation between hearing outcomes after different episodes of recurrent idiopathic sudden sensorineural hearing loss.

OBJECTIVES: Recurrent idiopathic sudden sensorineural hearing loss (ISSNHL) is a rare disease. In this study, we evaluated the correlations between hearing recovery after the first and recurrent episodes of ISSNHL and characterized the clinical features of different episodes of ISSNHL. METHODS: This retrospective study was conducted by reviewing medical records pertaining to the period 2008-2018. A total of 30 patients (16 male, 14 female) who had experienced at least two episodes of ISSNHL were included. All patients were had received steroid therapy (including systemic and IT) and/or hyperbaric oxygen therapy within 2 weeks after the onset of disease. The SDRG's criteria was used for the grading of hearing recovery. RESULTS: The median age at the first and second episode of ISSNHL was 48 and 53.5 years, respectively; a total of 30% of patients presented with vertigo in the first episode and 40% presented with vertigo in the second episode. The hearing outcomes of both episodes showed significant improvement after treatment. The rate of complete recovery after the first and second episodes was 46.67% and 33.33%, respectively. A significant positive correlation was observed between the treatment outcomes of the first and second episodes (r = 0.721, p < 0.001). CONCLUSION: In ISSNHL, hearing recovery after a recurrent episode is significantly correlated with the hearing outcome after the initial episode (p = 0.042). The treatment outcome of the first episode is a prognostic factor for the outcomes of recurrent episodes.

Usefulness of vertebrobasilar artery radiological finding as a predictive and prognostic factor for sudden sensorineural hearing loss.

OBJECTIVE: The association between sudden sensorineural hearing loss (SSNHL) and radiological findings of the vertebrobasilar artery is not well-known and little research has been done. We hypothesized that the radiological features of the vertebrobasilar artery contribute to the incidence and prognosis of SSNHL. METHODS: We retrospectively enrolled patients diagnosed with unilateral SSNHL (SSNHL group) and those with acute vestibular neuritis (AVN; control group) in our hospital. All patients underwent magnetic resonance imaging and computed tomography. We measured the following parameters on the radiological images: basilar artery diameter, direction and distance of basilar artery deviation, direction and distance of vertebral artery deviation, and incidence of vertebral artery obstruction. Pure tone audiometry (PTA) was performed in all patients. Follow up PTA between 1 week and 1 month after treatment was performed in the SSNHL group. RESULTS: A total of 244 SSNHL patients and 62 AVN patients were included in the analysis. Age, body mass index, and basilar artery diameter were found to be significantly associated with SSNHL. In the SSNHL group, patients were divided into three subgroups based on the consistency between the basilar artery deviation site and disease site. No significant difference was noted in initial PTA, final PTA, PTA recovery, and symptom improvement among the three groups. In case of the basilar artery, when the deviation and disease sites were in the opposite direction and the basilar artery diameter was >3.5 mm, diameter of basilar artery was positively correlated with PTA recovery. CONCLUSIONS: The strength of this study is that radiological evaluation of the vertebrobasilar artery was performed. Further research on the association between SSNHL and radiological features of the vertebrobasilar artery should be conducted to emphasize the importance of vascular assessment in SSNHL.

Effective sound therapy using a hearing aid and educational counseling in patients with chronic tinnitus.

OBJECTIVE: This study aimed to assess the effectiveness of our sound therapy with appropriate hearing aid fitting and periodic hearing aid adjustment in patients with chronic tinnitus. METHODS: We conducted a retrospective study. The study included 490 individuals who received treatment with hearing aids for chronic tinnitus at least for 3 months. To determine the effects of tinnitus on patients' quality of life, the participants completed a series of questionnaires, including the Tinnitus Handicap Inventory (THI), Visual Analogue Scale (VAS) for loudness and annoyance, and questionnaires of subjective symptom improvement. Data were collected at entry and 3 months and 1 year after treatment initiation. RESULTS: All 490 participants completed the questionnaires at 3 months; however, only 312 completed them at 1 year. The mean ± standard deviation THI score before treatment decreased significantly at 3 months (490 participants: 53 ± 25 to 11 ± 16 and 312 participants: 55 ± 24 to 12 ± 16) and 1 year (55 ± 24 to 9 ± 14) (P < 0.01). The mean VAS score for tinnitus loudness before treatment decreased significantly at 3 months (490 participants: 70 ± 22 to 25 ± 27 and 312 participants: 71 ± 22 to 27 ± 26) and 1 year (71 ± 22 to 21 ± 28) (P < 0.01). In addition, the mean VAS score for tinnitus annoyance before treatment decreased significantly at 3 months (490 participants: 75 ± 26 to 20 ± 26 and 312 participants: 75 ± 25 to 23 ± 27) and 1 year (75 ± 25 to 17 ± 26) (P < 0.01). Approximately 80% of patients noticed improvements in their tinnitus annoyance and loudness, as determined by their responses to the questionnaires of subjective symptom improvement. CONCLUSION: The results of this study suggest that treatment with sound therapy may ameliorate the symptoms of chronic tinnitus associated with hearing loss.

Cortical reorganization following auditory deprivation predicts cochlear implant performance in postlingually deaf adults.

Long-term hearing loss in postlingually deaf (PD) adults may lead to brain structural changes that affect the outcomes of cochlear implantation. We studied 94 PD patients who underwent cochlear implantation and 37 patients who were MRI-scanned within 2 weeks after the onset of sudden hearing loss and expected with minimal brain structural changes in relation to deafness. Compared with those with sudden hearing loss, we found lower gray matter (GM) probabilities in bilateral thalami, superior, middle, inferior temporal cortices as well as the central cortical regions corresponding to the movement and sensation of the lips, tongue, and larynx in the PD group. Among these brain areas, the GM in the middle temporal cortex showed negative correlation with disease duration, whereas the other areas displayed positive correlations. Left superior, middle temporal cortical, and bilateral thalamic GMs were the most accurate predictors of post-cochlear implantation word recognition scores (mean absolute error [MAE] = 10.1, r = .82), which was superior to clinical variables used (MAE: 12.1, p < .05). Using the combined brain morphological and clinical features, we achieved the best prediction of the outcome (MAE: 8.51, r = .90). Our findings suggest that the cross-modal plasticity allowing the superior temporal cortex and thalamus to process other modal sensory inputs reverses the initially lower volume when deafness becomes persistent. The middle temporal cortex processing higher-level language comprehension shows persistent negative correlations with disease duration, suggesting this area's association with degraded speech comprehensions due to long-term deafness. Morphological features combined with clinical variables might play a key role in predicting outcomes of cochlear implantation.

Comparison of Therapeutic Results with/without Additional Hyperbaric Oxygen Therapy in Idiopathic Sudden Sensorineural Hearing Loss: A Randomized Prospective Study.

OBJECTIVE: To assess the efficacy of the combination of hyperbaric oxygen (HBO) and pharmacological treatment in patients with idiopathic sudden sensorineural hearing loss (ISSNHL) and define patients amenable for HBO therapy. METHODS: Prospective, randomized, trial involving 136 cases with unilateral ISSNHL that were randomly divided into 2 groups: the pharmacological treatment (P) group and HBO + pharmacological treatment (HBO+P) group, which received additional HBO for 14 days besides the pharmacological treatments. Pure tone audiometry gain larger than 15 dBHL was defined as success, and the success rate of each group was calculated. RESULTS: The overall success rate of the HBO+P group and the P group is 60.6% (40/66) and 42.9% (30/70), respectively (p < 0.05). Furthermore, patients with mild-moderate baseline hearing loss, aged ≤50 years, receiving treatment in ≤14 days, or without accompanied dizziness/vertigo in the HBO+P group had higher success rate than the P group (p < 0.05). CONCLUSIONS: HBO combined with pharmacological treatments leads to better hearing recovery than pharmacological treatments alone.

Prediction of hearing outcomes by auditory steady-state response in patients with sudden sensorineural hearing loss.

BACKGROUND: There has been no report on the predictive value of auditory steady-state response (ASSR) in the hearing prognosis of sudden sensorineural hearing loss (SSNHL). AIMS/OBJECTIVES: To investigate whether ASSR can be a prognostic indicator of hearing outcome in patients with SSNHL after systemic steroid treatment. MATERIAL AND METHODS: Fifty-three patients with unilateral mild to severe SSNHL (≤90 dB HL at 0.5k, 1k, 2k, and 4 kHz, 4FA) were included. All patients received systemic high dose steroid therapy within one month after onset. The difference between the threshold levels measured by ASSR and PTA on the same day [ASSR - PTA] was calculated. The hearing recovery (HR) was defined as a < 30 dB HL of final degree of hearing loss and a > 15 dB HL of hearing gain. RESULTS: The HR (+) group showed significantly worse ASSR predicted threshold than pure-tone threshold in univariate (t(51) = 2.412, p = .020) and multivariate analysis (OR 0.910, p = .012). The [ASSR - PTA] threshold showed significantly moderate correlation with hearing gain (r = -0.303, p = .028). CONCLUSIONS: Worse ASSR predicted threshold than pure-tone threshold predicted poor hearing outcome after systemic steroid treatment in mild to severe unilateral SSNHL.

Relapse of rare diseases during COVID-19 pandemic: bicytopenia in an adult patient with thiamine-responsive megaloblastic anaemia.

Thiamine-responsive megaloblastic anaemia (TRMA) is a syndrome associated with megaloblastic anaemia, diabetes mellitus and sensorineural deafness, due to mutations in the SLC19A2gene, which codes for a thiamine carrier protein. Oral thiamine supplementation is the main treatment. We report the case of a 19-year-old man known for TRMA, who presented in the emergency department with bicytopenia (haemoglobin 5,4 g/dL, thrombocytes 38×109/L) revealed by dyspnea and chest pain. Investigations excluded bleeding, hemolysis, coagulopathy and iron deficiencies. A recent infection and an acute coronary syndrome have also been eliminated. We later found out that thiamine treatment had been discontinued three months before, due to general confinement in Tunisia during the COVID-19 pandemic. Parenteral administration of 100 mg of thiamine daily resulted in the recovery of haematopoiesis within three weeks.

Analysis of Click and Swept-Tone Auditory Brainstem Response Results for Moderate and Severe Sensorineural Hearing Loss.

INTRODUCTION: Auditory brainstem response (ABR) is one of the commonly used methods in clinical settings to evaluate the hearing sensitivity and auditory function. The current ABR measurement usually adopts click sound as the stimuli. However, there may be partial ABR amplitude attenuation due to the delay characteristics of the cochlear traveling wave along the basilar membrane. To solve that problem, a swept-tone method was proposed, in which the show-up time of different frequency components was adjusted to compensate the delay characteristics of the cochlear basilar membrane; therefore, different ABR subcomponents of different frequencies were synchronized. METHODS: The normal hearing group, moderate sensorineural hearing loss group, and severe sensorineural hearing loss group underwent click ABR and swept-tone ABR with different stimulus intensities. The latencies and amplitudes of waves I, III, and V in 2 detections were recorded. RESULTS: It was found that the latency of each of the recorded I, III, and V waves detected by swept-tone ABR was shorter than that by click ABR in both the control group and experimental groups. In addition, the amplitude of each of the recorded I, III, and V waves, except V waves under 60 dB nHL in the moderate sensorineural hearing loss group, detected by swept-tone ABR was larger than that by click ABR. The results also showed that the swept-tone ABR could measure the visible V waves at lower stimulus levels in the severe sensorineural hearing loss group. CONCLUSION: Swept-tone improves the ABR waveforms and helps to obtain more accurate threshold to some extent. Therefore, the proposed swept-tone ABR may provide a new solution for better morphology of ABR waveform, which can help to make more accurate diagnosis about the hearing functionality in the clinic.

Computer-assisted reading intervention for children with hearing impairment using cochlear implants: Effects on auditory event-related potentials and mismatch negativity.

OBJECTIVES: The primary aim was to find out whether a computer-assisted reading intervention program with a phonic approach can affect event-related (ERPs) and mismatch negativity (MMN) in hearing impaired (HI) children using cochlear implants (CIs). METHODS: This study involved a test group of 15 HI children with CIs and a control group of 14 normal hearing (NH) children. The children were 4 years and 10 months to 8 years and 1 month old. ERPs were recorded immediately before and after 4 weeks of training with a computer-assisted reading intervention, GraphoGame. A multi-feature paradigm, Optimum-1, was used, i.e. a standard stimulus alternated with five different deviants: gap intensity, pitch, location and duration. MMN was calculated from the mean amplitude ERP of each deviant minus the standard stimulus response in a specific time interval, 80 - 224 ms. Repeated measures ANOVA was used for the statistical analysis. RESULTS: The results did not show any significant changes with the computerassisted training in the ERPs and MMNs among the HI children with CIs. The presence of both MMN and a positive mismatch response (pMMR), which might reflect an immaturity, complicates interpreting the results in this age group. Individually, there was a mix of MMNs and pMMRs among all participants, pre and post training, and the change of each deviant after intervention was not predictable. CONCLUSIONS: There are no significant changes in ERP or MMN after intervention, however lack of significances must be interpreted with caution. Besides the presence of both MMNs and pMMRs, only modest changes are to be expected on an individual basis and small samples hinder making statistical conclusions regarding the training's effects. The study contributes to some more descriptive pieces of ERPs and MMNs among the HI children with CIs. The issues of MMN and pMMR are highlighted.

Hearing and Quality-of-Life Outcomes After Cochlear Implantation in Adult Hearing Aid Users 65 Years or Older: A Secondary Analysis of a Nonrandomized Clinical Trial.

Importance: Hearing loss, especially moderate to severe forms, has the potential to negatively affect an individual's physical, social, emotional, and cognitive well-being. Moreover, having ineffective binaural hearing increases difficulty understanding speech in noise and leads to a greater degree of social isolation and loneliness and a reduced quality of life (QoL). Objective: To explore the audiometric and holistic effects of cochlear implantation in a group of adults 65 years or older compared with an optimized bilateral hearing aid condition. Design, Setting, and Participants: This ad hoc secondary analysis of a prospective, single-subject, repeated-measures nonrandomized clinical trial included 13 cochlear implantation centers across the United States. Participants 65 years or older with postlingual bilateral moderate-to-profound sensorineural hearing loss with aided Consonant-Vowel Nucleus-Consonant (CNC) word scores in quiet of 40% or less in the ear to undergo implantation and 50% or less in the contralateral ear were included in the analysis. Baseline QoL testing was performed after 1 month of optimized bilateral hearing aid use. Participants were enrolled from February 20, 2017, to May 3, 2018, and follow-up was completed December 21, 2018. Data were analyzed from March 25, 2019, to March 31, 2020. Interventions: Unilateral implantation with a slim, modiolar cochlear implant device. Hearing aid use in the contralateral ear was required through the 6-month primary end-point interval. Main Outcomes and Measures: The primary objective was to evaluate speech perception before and 6 months after activation of a new cochlear implant. Secondary objectives were QoL metrics in the everyday listening condition before and 6 months after implantation. Results: Seventy participants (51 men [73%]) with a median age of 74 (range, 65-91) years were included in the analysis. No major adverse events occurred. Mixed-model analysis with estimated marginal means and 95% CIs compared preimplantation baseline performance with 6-month postimplantation performance. A clinically important improvement in CNC words was shown in the bimodal condition, with a mean difference of 37.2% (95% CI, 32.0%-42.4%), and in the unilateral (cochlear implant only) condition, with a mean difference of 44.1% (95% CI, 39.0%-49.2%). A clinically important improvement in noise (AzBio sentences signal-to-noise ratio of +10 dB) was also shown, with a mean difference of 21.6% (95% CI, 15.7%-27.5%) in the bimodal condition and 24.5% (95% CI, 18.3%-30.7%) in the unilateral condition. The Health Utilities Index Mark 3 multiple-attribute score improved by 0.186 (95% CI, 0.136-0.234); the Speech, Spatial, and Qualities of Hearing Scale total score improved by 2.58 (95% CI, 2.18-2.99); and a novel Device Use Questionnaire reported 94% of participants were satisfied with overall hearing in the everyday listening condition. Conclusions and Relevance: This subgroup analysis of patients 65 years or older enrolled in a within-subject clinical trial of cochlear implantation demonstrated clinically meaningful audiometric and QoL benefit with an acceptable risk profile. These findings suggest that cochlear implantation in older adults may facilitate the concept of healthy aging. Trial Registration: ClinicalTrials.gov Identifier: NCT03007472.

Diagnostic accuracy of CE Chirp.

OBJECTIVE: There has been an increase in the use of the CE-Chirp stimulus in automated auditory brainstem response (AABR) equipment for neonatal hearing screening. The purpose of this study is to evaluate the diagnostic accuracy of the LS CE-Chirp-evoked auditory brainstem response (ABR) compared to the click-evoked ABR for the identification of different degrees and configurations of sensorineural (SNHL) hearing loss. METHOD: 49 ears with mild to moderate SNHL were assessed: 16 ears with rising SNHL and 33 ears with sloping high frequency SNHL. Behavioural pure tone thresholds were obtained at 125-8000 Hz and ABR thresholds were measured using the click and LS CE-Chirp stimuli respectively. Click- and LS CE-Chirp-evoked thresholds were compared with each other and with behavioural pure tone average at 500, 1000, 2000 Hz (PTA), high frequency average at 2000, 4000, 8000 Hz (HFA) and low frequency average at 250, 500, 1000 Hz (LFA). Diagnostic accuracy of the two ABR stimuli was also compared by using ROC curves. RESULTS: Differences between click- and LS CE Chirp-evoked ABR, and behavioural thresholds were not statistically significant (p > 0.05). The highest significant correlations for ABR using clicks to behavioural thresholds was found at 2000 and 4000 Hz, whereas, the highest correlation for LS CE-Chirp ABRs to behavioural thresholds was found at 1000, 2000 and 4000 Hz (r > 0.7, p < 0.001). A very strong, positive correlation was found between both click (r = 0.805, p < 0.001) and LS CE-Chirp (r = 0.825, p < 0.001) and the behavioural PTA. LS CE-Chirp ABR thresholds were closer to mid and low frequency thresholds than the click ABR while the click-evoked thresholds were in closer proximity to HFA. Sensitivity and specificity and false negative rates were identical. Diagnostic accuracy of the LS CE-Chirp ABR was equal to or better than click for low (area under the curve (AUC) = 0.83), mid (AUC = 0.89) and high frequency hearing losses (AUC = 0.73). However, scatterplots indicated more frequent underestimation of behavioural pure tone thresholds at mid and high frequencies with the LS CE-Chirp than for the click ABR. CONCLUSION: The diagnostic accuracy of the LS CE Chirp-evoked ABR is equivalent or better than the click-evoked ABR. The importance of ongoing surveillance and consideration of ABR screening protocols is consequently emphasized.

The derived-band envelope following response and its sensitivity to sensorineural hearing deficits.

The envelope following response (EFR) has been proposed as a non-invasive marker of synaptopathy in animal models. However, its amplitude is affected by the spread of basilar-membrane excitation and other coexisting sensorineural hearing deficits. This study aims to (i) improve frequency specificity of the EFR by introducing a derived-band EFR (DBEFR) technique and (ii) investigate the effect of lifetime noise exposure, age and outer-hair-cell (OHC) damage on DBEFR magnitudes. Additionally, we adopt a modelling approach to validate the frequency-specificity of the DBEFR and test how different aspects of sensorineural hearing loss affect peripheral generators. The combined analysis of simulations and experimental data proposes that the DBEFRs extracted from the [2-6]-kHz frequency band is a sensitive and frequency-specific measure of synaptopathy in humans. Individual variability in DBEFR magnitudes among listeners with normal audiograms was explained by their self-reported amount of experienced lifetime noise-exposure and corresponded to amplitude variability predicted by synaptopathy. Older listeners consistently had reduced DBEFR magnitudes in comparison to young normal-hearing listeners, in correspondence to how age-induced synaptopathy affects EFRs and compromises temporal envelope encoding. To a lesser degree, OHC damage was also seen to affect the DBEFR magnitude, hence the DBEFR metric should ideally be combined with a sensitive marker of OHC damage to offer a differential diagnosis of synaptopathy in listeners with impaired audiograms.

Binaural cue sensitivity in cochlear implant recipients with acoustic hearing preservation.

Bilateral acoustic hearing in cochlear implant (CI) recipients with hearing preservation may allow access to binaural cues. Sensitivity to acoustic binaural cues has been shown in some listeners combining electric and acoustic stimulation (EAS), yet remains poorly understood and may be subject to limitations imposed by the electrical stimulation and/or amplification asymmetries. The purpose of this study was to investigate the effect of stimulus level, frequency-dependent gain, and the addition of unilateral electrical stimulation on sensitivity to low-frequency binaural cues. Thresholds were measured for interaural time and level differences (ITD and ILD) carried by a low-frequency, bandpass noise (100-800 Hz). 16 adult CI EAS listeners (mean age = 50.2 years) each participated in three listening conditions: acoustic hearing only at 90 dB SPL, acoustic hearing only at 60 dB SPL with frequency-dependent gain, and acoustic hearing plus unilateral CI at 60 dB SPL with frequency-dependent gain applied to the acoustic channels only. Results revealed thresholds within the ecologically relevant ITD and/or ILD range for most EAS listeners. No significant effects of presentation level, frequency-dependent gain, or the addition of unilateral electrical stimulation on the resultant thresholds for ITDs or ILDs were observed at the group level. Correlational analyses related ITD and ILD thresholds to the degree of EAS benefit (i.e., advantage of acoustic hearing in the implanted ear) for speech recognition in diffuse noise. There was a significant relationship between EAS benefit and ITD thresholds, but no statistically significant relationship between EAS benefit and ILD thresholds. In summary, the results of this study are not consistent with our previous data obtained with simulated EAS in normal-hearing listeners, which showed significant binaural interference by a unilateral electrical "distractor" (Van Ginkel et al., 2019). The difference between studies suggests that chronic exposure to unilateral electrical stimulation combined with bilateral acoustic stimulation may reduce interference effects, perhaps because listeners adapt to the presence of the constant but binaurally incongruous CI stimulus. These results are consistent with past studies that demonstrated no interference in spatial hearing tasks due to the addition of a unilateral CI in adult EAS listeners.

Uncovered p1 and p2 waves preceding the N3 vestibular evoked neurogenic potential in profound sensorineural hearing loss.

BACKGROUND: The N3 wave is a vestibular evoked neurogenic potential detected in some patients with profound sensorineural hearing loss (PSNHL) during brainstem auditory evoked potential (BAEP) analysis. In 1998, Kato et al. mentioned two electropositive waves preceding N3, which we named p1-p2, but no further description was given. OBJECTIVE: We sought to demonstrate the reproducibility of these waves and hypothesize on their anatomic origin. METHODS: We used two cohorts of patients with PSNHL. The first cohort comprised 10 patients with N3, allowing us to establish a new test with adequate electrophysiological conditions headed to detect p1-p2 waves (PN3EP). The second cohort consisted of two groups: group A comprised 10 patients in whom N3 was not detected; and group B comprised 20 patients presenting N3. PN3EP was performed in both groups, of which 50% had cervical myogenic vestibular evoked potentials (cVEMPs). RESULTS: Only group B presented p1-p2. The PN3EP facilitated the identification of p1-p2 over BAEP analysis, and their presence correlated well with cVEMPs. CONCLUSIONS: P1-p2 may be covered due to inadequate BAEP setting conditions, and could be generated in the distal neural path that generates the N3 wave.

Effects of Sensorineural Hearing Loss on Cortical Synchronization to Competing Speech during Selective Attention.

When selectively attending to a speech stream in multi-talker scenarios, low-frequency cortical activity is known to synchronize selectively to fluctuations in the attended speech signal. Older listeners with age-related sensorineural hearing loss (presbycusis) often struggle to understand speech in such situations, even when wearing a hearing aid. Yet, it is unclear whether a peripheral hearing loss degrades the attentional modulation of cortical speech tracking. Here, we used psychoacoustics and electroencephalography (EEG) in male and female human listeners to examine potential effects of hearing loss on EEG correlates of speech envelope synchronization in cortex. Behaviorally, older hearing-impaired (HI) listeners showed degraded speech-in-noise recognition and reduced temporal acuity compared with age-matched normal-hearing (NH) controls. During EEG recordings, we used a selective attention task with two spatially separated simultaneous speech streams where NH and HI listeners both showed high speech recognition performance. Low-frequency (<10 Hz) envelope-entrained EEG responses were enhanced in the HI listeners, both for the attended speech, but also for tone sequences modulated at slow rates (4 Hz) during passive listening. Compared with the attended speech, responses to the ignored stream were found to be reduced in both HI and NH listeners, allowing for the attended target to be classified from single-trial EEG data with similar high accuracy in the two groups. However, despite robust attention-modulated speech entrainment, the HI listeners rated the competing speech task to be more difficult. These results suggest that speech-in-noise problems experienced by older HI listeners are not necessarily associated with degraded attentional selection.SIGNIFICANCE STATEMENT People with age-related sensorineural hearing loss often struggle to follow speech in the presence of competing talkers. It is currently unclear whether hearing impairment may impair the ability to use selective attention to suppress distracting speech in situations when the distractor is well segregated from the target. Here, we report amplified envelope-entrained cortical EEG responses to attended speech and to simple tones modulated at speech rates (4 Hz) in listeners with age-related hearing loss. Critically, despite increased self-reported listening difficulties, cortical synchronization to speech mixtures was robustly modulated by selective attention in listeners with hearing loss. This allowed the attended talker to be classified from single-trial EEG responses with high accuracy in both older hearing-impaired listeners and age-matched normal-hearing controls.

Narrow-band ripple glide direction discrimination and its relationship to frequency selectivity estimated using psychophysical tuning curves.

The highest spectral ripple density at which the discrimination of ripple glide direction was possible (STRtdir task) was assessed for one-octave wide (narrowband) stimuli with center frequencies of 500, 1000, 2000, and 4000 Hz and for a broadband stimulus. A pink noise lowpass filtered at the lower edge frequency of the rippled-noise stimuli was used to mask possible combination ripples. The relationship between thresholds measured using the STRtdir task and estimates of the sharpness of tuning (Q10) derived from fast psychophysical tuning curves was assessed for subjects with normal hearing (NH) and cochlear hearing loss (CHL). The STRtdir thresholds for the narrowband stimuli were highly correlated with Q10 values for the same center frequency, supporting the idea that STRtdir thresholds for the narrowband stimuli provide a good measure of frequency resolution. Both the STRtdir thresholds and the Q10 values were lower (worse) for the subjects with CHL than for the subjects with NH. For both the NH and CHL subjects, mean STRtdir thresholds for the broadband stimulus were not significantly higher (better) than for the narrowband stimuli, suggesting little or no ability to combine information across center frequencies.

A model of auditory brainstem response wave I morphology.

Use of the auditory brainstem response (ABR) in research has increased in the search for physiological correlates of noise-induced damage to the cochlea. The extraction of data from the ABR has traditionally relied on visual determination of peaks and troughs to calculate metrics such as wave amplitude. Visual determination can be reliable when evaluated by trained, experienced personnel, but noisy waveforms and overlapping waves produce uncertain data. The present study proposes and validates a method of fitting summed Gaussian functions to the summating potential and wave I of the ABR. This method could be useful to the research community studying these potentials by providing more accurate measures of wave amplitude than by visual determination.

Recurrences in Sudden Sensorineural Hearing Loss: A Long-Term Observational Study.

Purpose Long-term outcomes of sudden sensorineural hearing loss (SSNHL) are poorly studied. The recurrence rate is heterogeneous, and the prognosis of relapses is uncertain. The aim of this retrospective study was to evaluate the recurrence rate of SSNHL and to analyze the correlation with clinical and audiometric characteristics. Method Seventy-three patients with idiopatic SSNHL were evaluated. Clinical and audiometric features were recorded. Seventy patients (95.8%) had at least a 2-year follow-up, whereas 50 (68.4%) had a 5-year follow-up. Results Two- and 5-year recurrence rates were 5.60% and 10.34%, respectively. Mean time lapse between 1st episode and recurrence was 29.33 ± 26.60 months. About 70% of patients had a partial recovery at recurrence. The same ear was affected in 42.8% of patients, the contralateral ear was affected in 42.8% of patients, and recurrence was bilateral in 14.4% of cases. Recurrence correlated only with the presence of tinnitus during follow-up. However, the small number of participants with recurrence represented a limiting factor of our study. Conclusions Recurrences of SSNHL are rare events that can involve ipsilateral or contralateral ear. Further studies are necessary to identify predictors of recurrence.