One of the main mechanisms used by neurons and glial cells to promote repair following brain injury is to upregulate activity-dependent molecules such as insulin-like growth factor 1 (IGF-1) and interleukin-1β (IL-1β). In the auditory system, IGF-1 is crucial for restoring synaptic transmission following hearing loss; however, whether IL-1β is also involved in this process is unknown. In this study, we evaluated the expression of IGF-1 and IL-1β within neurons and glial cells of the ventral cochlear nucleus in adult rats at 1, 7, 15 and 30 days following bilateral cochlear ablation. After the lesion, significant increases in both the overall mean gray levels of IGF-1 immunostaining and the mean gray levels within cells of the cochlear nucleus were observed at 1, 7 and 15 days compared with control animals. The expression and distribution of IL-1β in the ventral cochlear nucleus of ablated animals was temporally and spatially correlated with IGF-1. We also observed a lack of colocalization between IGF-1 and IL-1β with either astrocytes or microglia at any of the time points following ablation. These results suggest that the upregulation of IGF-1 and IL-1β levels within neurons - but not within glial cells - may reflect a plastic mechanism involved in repairing synaptic homeostasis of the overall cellular environment of the cochlear nucleus following bilateral cochlear ablation. J. Comp. Neurol., 2013. © 2013 Wiley Periodicals, Inc.

Second language (L2) instruction programs often ask learners to repeat aloud words spoken by a native speaker. However, recent research on retrieval practice has suggested that imitating native pronunciation might be less effective than drill instruction, wherein the learner is required to produce the L2 words from memory (and given feedback). We contrasted the effectiveness of imitation and retrieval practice drills on learning L2 spoken vocabulary. Learners viewed pictures of objects and heard their names; in the imitation condition, they heard and then repeated aloud each name, whereas in the retrieval practice condition, they tried to produce the name before hearing it. On a final test administered either immediately after training (Exp. 1) or after a 2-day delay (Exp. 2), retrieval practice produced better comprehension of the L2 words, better ability to produce the L2 words, and no loss of pronunciation quality.

IMPORTANCE The unpredictability of idiopathic sudden sensorineural hearing loss (ISSNHL) presents a challenge to preventive care. Our study confirms the potentially important role of the 3-T magnetic resonance imaging (MRI), and in particular of the 3-dimensional fluid-attenuated inversion-recovery (3D-FLAIR) sequence, in the diagnosis and prognosis of ISSNHL to guide medical treatment.

OBJECTIVE

To confirm the diagnostic, clinical, and prognostic role of 3D-FLAIR MRI in patients with idiopathic sudden sensorineural hearing loss (ISSNHL). DESIGN, SETTING, AND PATIENTS Retrospective study in a tertiary referral center with a consecutive sample of 23 patients diagnosed as having unilateral ISSNHL from January 2010 to March 2011. EXPOSURES Patients underwent 3D-FLAIR MRI at 3 T to evaluate ISSNHL, and the MRI images were compared with those belonging to a random group of 20 age-matched healthy patients. MAIN OUTCOMES AND MEASURES Precontrast and postcontrast high-intensity 3D-FLAIR MRI findings in patients with ISSNHL and the correlation with clinical findings.

RESULTS

Thirteen patients showed high-intensity signals in the affected inner ear on precontrast and postcontrast 3D-FLAIR MRI (57%). From the analysis of different MRI sequences, we posited 3 radiologic patterns likely correlated with mild hemorrhage, acute inflammation, and presence or absence of blood-labyrinth or nerve barrier (BLB) breakdown. Hypersignal on 3D-FLAIR MRI was positively associated with pretreatment hearing loss (P = .04) and presence of vertigo (P = .04). A strict correlation also existed between distribution of the signal (vestibule, semicircular canals) and clinical features (vertigo) (P = .04).

CONCLUSIONS

AND RELEVANCE Use of 3D-FLAIR MRI at 3 T may contribute to the elucidation of pathologic conditions in the inner ears of patients with ISSNHL and provide new radiologic indicators (mild hemorrhage, acute inflammation, presence or absence of BLB breakdown) that might assume the role of prognostic factors.

Hearing loss is the most frequent sensory disorder. It affects 3 in 1000 newborns. It is genetically heterogeneous with 60 causally-related genes identified to date. Mutations in GJB2 gene account for half of all cases of non-syndromic deafness. The aim of this study was to determine the relative frequency of GJB2 allele variants in Tunisia. In this study, we screened 138 patients with congenital hearing loss belonging to 131 families originating from different parts of Tunisia for mutations in GJB2 gene. GJB2 mutations were found in 39% of families (51/131). The most common mutation was c.35delG accounting for 35% of all cases (46/131). The second most frequent mutation was p.E47X present in 3.8% of families. Four identified mutations in our cohort have not been reported in Tunisia; p.V37I, c.235delC, p.G130A and the splice site mutation IVS1+1G>A (0.76%). These previously described mutations were detected only in families originating from Northern and not from other geographical regions in Tunisia. In conclusion we have confirmed the high frequency of c.35delG in Tunisia which represents 85.4% of all GJB2 mutant alleles. We have also extended the mutational spectrum of GJB2 gene in Tunisia and revealed a more pronounced allelic heterogeneity in the North compared to the rest of the country.

ObjectiveCochlear nerve deficiency (CND) is increasingly diagnosed in children with sensorineural hearing loss (SNHL). We sought to determine the prevalence of CND, its imaging characteristics, and correlations with audiologic phenotype in children with unilateral SNHL.DesignCase series with chart review.SettingTertiary pediatric hospital.Subjects/MethodsIn 128 consecutive children with unilateral SNHL who underwent high-resolution magnetic resonance imaging, the diameters, area, and signal intensity of the cochlear nerve (CN) were measured and normalized to the ipsilateral facial nerve. Presence of CND was determined by comparison to normative data. Relationships among hearing loss severity, progression, and nerve size were investigated.ResultsCochlear nerve deficiency was present in 26% of children with unilateral SNHL. Its prevalence was higher (48%) in severe to profound SNHL, especially when in infants (100%). Width of the bony cochlear nerve canal (BCNC) correlated strongly with relative CN diameter, density, and area (R = 0.5); furthermore, a narrow BCNC (<1.7 mm) strongly predicted CND. Severity of hearing loss modestly correlated with nerve size, although significant variability was observed. Progression never occurred unless there were other inner ear malformations, whereas in the non-CND group, it occurred in 22%. Ophthalmologic abnormalities were very common (67%) in CND children, particularly oculomotor disturbances.ConclusionCochlear nerve deficiency is a common cause of unilateral SNHL, particularly in congenital unilateral deafness. Width of the BCNC effectively predicts CND, a finding useful when only computed tomography imaging is available. In an ear with CND, hearing can be expected to remain stable over time. Diagnosis should prompt evaluation by an ophthalmologist.

To investigate the relationship of bilirubin/albumin (B/A) ratio and acidosis with abnormal brainstem auditory evoked potentials (BAEPs) in neonates with severe hyperbilirubinemia and its clinical significance.A total of 967 neonates with severe hyperbilirubinemia between November 2008 and October 2009 were enrolled in the study. They were divided into two groups according to their BAEPs: normal BAEP group (n=799) and abnormal BAEP group (n=168). Univariate analysis and age-stratified Chi-square test were used to determine the relationship of B/A ratio and acidosis with BAEP.The univariate analysis showed that the abnormal BAEP group had significantly lower pH and base excess values and a significantly higher B/A ratio compared with the normal BAEP group (P<0.05). The age-stratified Chi-square test showed that neonates with acidosis or with a B/A ratio greater than 1.0 had a significantly higher incidence of abnormal BAEPs than those without acidosis or with a B/A ratio less than 1.0 in any age (days) group of neonates with severe hyperbilirubinemia (P<0.05).High B/A ratio and acidosis are the risk factors for abnormal BAEPs in neonates with severe hyperbilirubinemia, which is the case for those in any age group. In order to reduce the incidence of hearing loss in any age group of neonates with severe hyperbilirubinemia, we should correct the acidosis and lower the B/A ratio as soon as possible.

Abstract

Conclusion:

Active middle ear implant (AMEI) implantation in children and adolescents is safe and provides improved hearing results. No statistical difference in hearing outcomes was shown in the group of patients affected by chronic middle ear diseases versus aural atresia. Also, the transducer location (round window versus oval window placement) did not lead to different outcomes in hearing abilities.

Objectives:

(1) To assess the hearing outcomes with the active implant Vibrant Soundbridge (VSB) in children and adolescents. (2) To evaluate whether functional results of the subjects in the study could depend on the hearing loss etiology (chronic middle ear diseases versus aural atresia) or on transducer location (round window versus oval window placement).

Methods:

The study was carried out with a retrospective, single-subject, repeated measures design, and included 22 children and adolescents with conductive or mixed hearing loss due to aural atresia or chronic middle ear diseases. Preoperative and postoperative pure tone air conduction (AC) and bone conduction (BC) thresholds were measured to demonstrate implantation safety. Free-field warble tone and speech audiometry were performed to assess postoperative hearing abilities with and without the VSB.

Results:

No significant changes in mean BC or AC thresholds between preoperative and postoperative conditions were seen in the 22 patients. Mean PTA4 functional gain was 30.7 dB. Averaged over all 22 patients, word recognition at 65 dB SPL changed from an average of 19% in the unaided postoperative condition to 97% in the VSB-aided condition. Functional results were independent of hearing loss etiology and transducer location.

Abstract

Conclusions:

Physicians should consider additional treatment strategies for Meniere's disease patients with a long history of disease and hearing loss in the secondary affected ear and also provide psychological support regarding future progressive bilateral hearing loss.

Objectives:

To treat intractable Meniere's disease patients effectively, we need to understand the psychological condition of each patient. We examined the state of neurosis and depression in patients and correlated this with demographic and background information.

Methods:

Between 1998 and 2009, we enrolled 207 patients with intractable Meniere's disease in this prospective study. We used the Cornell Medical Index and the Self-rating Depression Scale to evaluate their psychological condition. We also obtained demographic and background information relating to sex, age, duration of disease, vertigo frequency, hearing level in bilateral sides, and plasma vasopressin level.

Results:

Neurosis and depression was diagnosed in 40.1% and 60.4%, respectively, of patients with intractable Meniere's disease. Our results showed that surgical treatment significantly improved vertigo and hearing ability in patients with no psychological symptoms compared with those exhibiting psychological symptoms. Patients with a longer duration and worse hearing level in the secondary affected ear had a significantly higher incidence of mental illness than those with a shorter duration and better level of hearing.

Auditory training involves active listening to auditory stimuli and aims to improve performance in auditory tasks. As such, auditory training is a potential intervention for the management of people with hearing loss.This systematic review (PROSPERO 2011: CRD42011001406) evaluated the published evidence-base for the efficacy of individual computer-based auditory training to improve speech intelligibility, cognition and communication abilities in adults with hearing loss, with or without hearing aids or cochlear implants.A systematic search of eight databases and key journals identified 229 articles published since 1996, 13 of which met the inclusion criteria. Data were independently extracted and reviewed by the two authors. Study quality was assessed using ten pre-defined scientific and intervention-specific measures.Auditory training resulted in improved performance for trained tasks in 9/10 articles that reported on-task outcomes. Although significant generalisation of learning was shown to untrained measures of speech intelligibility (11/13 articles), cognition (1/1 articles) and self-reported hearing abilities (1/2 articles), improvements were small and not robust. Where reported, compliance with computer-based auditory training was high, and retention of learning was shown at post-training follow-ups. Published evidence was of very-low to moderate study quality.Our findings demonstrate that published evidence for the efficacy of individual computer-based auditory training for adults with hearing loss is not robust and therefore cannot be reliably used to guide intervention at this time. We identify a need for high-quality evidence to further examine the efficacy of computer-based auditory training for people with hearing loss.

OBJECTIVES:

: The purpose of the present investigation was to define for young, middle-aged, and older adults the optimal frequency (cies) to record both the cervical vestibular-evoked myogenic potential (cVEMP) and the ocular vestibular-evoked myogenic potential (oVEMP). Further, this study aimed to describe age-related changes in the tuning of these two vestibular-evoked myogenic potentials.

DESIGN:

: This was a prospective study. Participants were 39 healthy adults (mean age 46.3 ± 15.7 years; range = 22 to 78 years; 15 men) equally divided into 3 age groups of 13 participants each: young adult (18 to 39 years), middle age (40 to 59 years), and old adult (≥60 years). cVEMPs and oVEMPs were recorded using air-conduction tone bursts at stimulus frequencies of 125, 250, 500, 750, 1000, 1500, and 2000 Hz presented at 127 dB pSPL.

RESULTS::

There was a significant main effect of age group and frequency on the amplitude of both the cVEMP and the oVEMP. Amplitudes were largest for the Young adult group for the cVEMP and for the young adult and Middle age group for the oVEMP. The largest average peak-to-peak amplitude occurred in response to a 750 Hz tone burst for both responses. No significant differences in mean amplitude of the cVEMP or oVEMP were observed for 500, 750, or 1000 Hz stimuli. There was a significant interaction of age group and frequency for the cVEMP, suggesting a loss of tuning for the old adult group. Compared with the young adult group, the tuning of the cVEMP and oVEMP for the older adjults appeared to shift to a higher frequency.

CONCLUSION:

: There is no sharp tuning in the saccule and utricle. Instead, there is a range of best frequencies that may be used to evoke the cVEMP and oVEMP responses. The results of the present investigation also demonstrate that the optimal stimulus frequency to elicit a VEMP may change with age. Accordingly, 500 Hz may not be the ideal frequency to elicit VEMPs for all age groups. For this reason, in cases where the VEMP response is absent at 500 Hz it is recommended that attempts be made to record the VEMP for tone-burst frequencies of 750 or 1000 Hz.