Auditory changes in awake guinea pigs exposed to overcompressed music.

Exposure to loud sound during leisure time is identified as a significant risk factor for hearing by health authorities worldwide. The current standard that defines unsafe exposure rests on the equal-energy hypothesis, according to which the maximum recommended exposure is a tradeoff between level and daily exposure duration, a satisfactory recipe except for strongly non-Gaussian intense sounds such as gunshots. Nowadays, sound broadcast by music and videoconference streaming services makes extensive use of numerical dynamic range compression.

Non-invasive intracranial pressure monitoring for high-grade gliomas patients treated with radiotherapy: results of the GMaPIC trial.

Introduction: Patients with high-grade gliomas are at risk of developing increased intracranial hypertension (ICHT) in relation to the increase in volume of their tumor. ICP change cannot be measured by invasive method but can be estimated by using routine clinical signs, in combination with a standard imaging method, magnetic resonance imaging (MRI). A non-invasive monitoring of ICP could be of interest in high-grade glioma, in particular after radiotherapy treatment with as major side effect a cerebral oedema.

Psychometric Validation of a Hearing Screening Questionnaire for Preschoolers Based on Language Development Evaluation by Caregivers.

Introduction: This study aimed to validate three age-adjusted versions of a Hearing Screening Questionnaire for Preschoolers, in Brazilian Portuguese, based on parents' perception of their children's hearing and oral language.

Methods: Psychometric validation was conducted on three questionnaires, each comprising nine items with yes/no responses. Three items focused on hearing screening at birth, and six assessed hearing and oral language.

Pathophysiology of Postoperative Hearing Disorders after Vestibular Schwannoma Resection: Insights from Auditory Brainstem Response and Otoacoustic Emissions.

: In order to better understand the pathophysiology of surgically induced hearing loss after vestibular schwannoma (VS) surgery, we postoperatively analyzed the hearing status in a series of patients where hearing was at least partially preserved. : Hearing was assessed through tonal audiometry, speech discrimination score, maximum word recognition score (dissyllabic word lists-MaxIS), otoacoustic emissions (OAEs), and auditory brainstem response (ABR). The magnetic resonance imaging (MRI) tumor characterization was also noted.

Prevalence of hearing loss and health vulnerability in children aged 25 to 36 months: an analysis of spatial distribution.

Purpose: To analyze the association between hearing loss and health vulnerability in children aged 25 to 36 months.

Methods: Analytical observational cross-sectional study conducted through child hearing screening in nine day-care centers. The screening consisted of anamnesis, otoscopy, tympanometry, transient otoacoustic emissions, and pure tone audiometry.

Preserved Auditory Steady State Response and Envelope-Following Response in Severe Brainstem Dysfunction Highlight the Need for Cross-Checking.

Objectives: Commercially available auditory steady state response (ASSR) systems are widely used to obtain hearing thresholds in the pediatric population objectively. Children are often examined during natural or induced sleep so that the recorded ASSRs are of subcortical origin, the inferior colliculus being often designated as the main ASSR contributor in these conditions. This report presents data from a battery of auditory neurophysiological objective tests obtained in 3 cases of severe brainstem dysfunction in sleeping children.

The SNARE protein SNAP-25 is required for normal exocytosis at auditory hair cell ribbon synapses.

Hearing depends on fast and sustained calcium-dependent synaptic vesicle fusion at the ribbon synapses of cochlear inner hair cells (IHCs). The implication of the canonical neuronal SNARE complex in this exocytotic process has so far remained controversial. We investigated the role of SNAP-25, a key component of this complex, in hearing, by generating and analyzing a conditional knockout mouse model allowing a targeted postnatal deletion of in IHCs.

mutations cause hypogonadotropic hypogonadism with sensory and cognitive deficits that can be reversed in infantile mice.

The nitric oxide (NO) signaling pathway in hypothalamic neurons plays a key role in the regulation of the secretion of gonadotropin-releasing hormone (GnRH), which is crucial for reproduction. We hypothesized that a disruption of neuronal NO synthase (NOS1) activity underlies some forms of hypogonadotropic hypogonadism. Whole-exome sequencing was performed on a cohort of 341 probands with congenital hypogonadotropic hypogonadism to identify ultrarare variants in .

Impaired auditory neural performance, another dimension of hearing loss in type-2 diabetes mellitus.

Aim: To evaluate auditory performance in subjects with poorly controlled type-2 diabetes mellitus, using a simple test battery assessing sensitivity to pure tones and neuronal function.

Methods: Enrolled subjects, aged between 23 and 79 years, reported several auditory dysfunctions. They were tested using pure-tone audiometry, otoacoustic emissions for cochlear-function evaluation, and measurement of middle-ear muscle-reflex thresholds in search of an auditory neuropathy.

Wideband tympanometry patterns in relation to intracranial pressure.

Wideband tympanometry performs a more thorough analysis of middle-ear mechanics than the conventional single-frequency method with a 226-Hz probe tone. The present work examines the sensitivity of wideband tympanometry to the stiffness of the stapes-annular ligament system in relation to intracranial pressure (ICP) and labyrinthine fluid pressure. Here, body tilt allowed ICP to be set at different values.

Decreased Reemerging Auditory Brainstem Responses Under Ipsilateral Broadband Masking as a Marker of Noise-Induced Cochlear Synaptopathy.

Objectives: In mammals, a 2-hr exposure to an octave-band noise (OBN) at 100 to 108 dB SPL induces loss of synaptic ribbons between inner hair cells and auditory nerve fibers with high thresholds of response (hiT neurons), that encode high-intensity sounds. Here, we tackle the challenge of diagnosing this synaptopathy by a noninvasive functional audiological test, ultimately in humans, despite the expected absence of auditory-threshold elevation and of clear electrophysiological abnormality, hiT neuron contributions being hidden by those of more sensitive and robust neurons.

Design: The noise-induced synaptopathy was replicated in mice (at 94, 97, and 100 dB SPL; n = 7, 7, and 8, respectively, against 8 unexposed controls), without long-lasting auditory-threshold elevation despite a twofold decrease in ribbon-synapse number for the 100-dB OBN exposure.

Meniere's attack - a volume or pressure phenomenon?

Meniere's disease (MD) still raises since its discovery in 1860 pathophysiological and etiopathogenical issues. The main pathophysiological feature that has emerged for decades is an anatomic one, the endolymphatic hydrops (EH), defined by the inflation of the endolymphatic part of the membranous labyrinth. However, the causal relationship between EH and MD has not been proven.

Subcortical neural generators of the envelope-following response in sleeping children: A transfer function analysis.

Multiple auditory structures, from cochlea to cortex, phase-lock to the envelope of complex stimuli. The relative contributions of these structures to the human surface-recorded envelope-following response (EFR) are still uncertain. Identification of the active contributor(s) is complicated by the fact that even the simplest two-tone (f&f) stimulus, targeting its (f-f) envelope, evokes additional linear (f&f) and non-linear (2f-f) phase-locked components as well as a transient auditory brainstem response (ABR).

Ultrarare heterozygous pathogenic variants of genes causing dominant forms of early-onset deafness underlie severe presbycusis.

Presbycusis, or age-related hearing loss (ARHL), is a major public health issue. About half the phenotypic variance has been attributed to genetic factors. Here, we assessed the contribution to presbycusis of ultrarare pathogenic variants, considered indicative of Mendelian forms.

Auditory biophysics of endolymphatic hydrops.

Audiological tests in patients with Menière's disease reveal abnormal patterns relevant for diagnostic purposes with some success. Electrocochleography, otoacoustic emissions and immittance measurements share a moderate sensitivity but a good specificity. Their potential for monitoring the patients suggests means to understand the characteristic time course of Menière's disease and the pathophysiology behind its attacks.

Frequency selectivity of tonal language native speakers probed by suppression tuning curves of spontaneous otoacoustic emissions.

Native acquisition of a tonal language (TL) is related to enhanced abilities of pitch perception and production, compared to non-tonal language (NTL) native speakers. Moreover, differences in brain responses to both linguistically relevant and non-relevant pitch changes have been described in TL native speakers. It is so far unclear to which extent differences are present at the peripheral processing level of the cochlea.

Auditory Brainstem Changes in Timing may Underlie Hyperacusis in a Salicylate-induced Acute Rat Model.

Hyperacusis, an exaggerated, sometimes painful perception of loudness even for soft sounds, is a poorly understood distressing condition. While the involvement of modified gain of central auditory neurons and the influence of nonauditory brain regions are well-documented, the issue of where in the auditory system these abnormalities arise remains open, particularly when hyperacusis comes without sensorineural hearing loss. Here we used acute intraperitoneal administration of sodium salicylate (150 mg/kg) in rats, enough to produce > 10-dB decrease in acoustic startle threshold with mild hearing loss at low frequencies (<10 kHz).

Otogelin, otogelin-like, and stereocilin form links connecting outer hair cell stereocilia to each other and the tectorial membrane.

The function of outer hair cells (OHCs), the mechanical actuators of the cochlea, involves the anchoring of their tallest stereocilia in the tectorial membrane (TM), an acellular structure overlying the sensory epithelium. Otogelin and otogelin-like are TM proteins related to secreted epithelial mucins. Defects in either cause the DFNB18B and DFNB84B genetic forms of deafness, respectively, both characterized by congenital mild-to-moderate hearing impairment.

Biasing the semicircular canal cupula in excitatory direction decreases the gain of the vestibuloocular reflex for head impulses.

Background: It has been shown that cold caloric irrigation decreases the vestibulo-ocular reflex (VOR) gain in the vertically positioned lateral canal as measured by head impulse testing. This effect is most probably caused by a sustained deflection of the cupula in the inhibitory direction.

Objective: The aim of the present experiment was to answer the question if a sustained excitatory deflection increases the gain of the reflex in healthy volunteers.

Pejvakin-mediated pexophagy protects auditory hair cells against noise-induced damage.

Noise overexposure causes oxidative stress, leading to auditory hair cell damage. Adaptive peroxisome proliferation involving pejvakin, a peroxisome-associated protein from the gasdermin family, has been shown to protect against this harmful oxidative stress. However, the role of pejvakin in peroxisome dynamics and homeostasis remains unclear.

Dual AAV-mediated gene therapy restores hearing in a DFNB9 mouse model.

Autosomal recessive genetic forms (DFNB) account for most cases of profound congenital deafness. Adeno-associated virus (AAV)-based gene therapy is a promising therapeutic option, but is limited by a potentially short therapeutic window and the constrained packaging capacity of the vector. We focus here on the otoferlin gene underlying DFNB9, one of the most frequent genetic forms of congenital deafness.

Generalization of the primary tone phase variation method: An exclusive way of isolating the frequency-following response components.

The primary tone phase variation (PTPV) technique combines selective sub-averaging with systematic variation of the phases of multitone stimuli. Each response component having a known phase relationship with the stimulus components phases can be isolated in the time domain. The method was generalized to the frequency-following response (FFR) evoked by a two-tone ( and ) stimulus comprising both linear and non-linear, as well as transient components.

Vestibular-evoked myogenic potential triggered by galvanic vestibular stimulation may reveal subclinical alterations in human T-cell lymphotropic virus type 1-associated myelopathy.

Background: Vestibular-evoked myogenic potential triggered by galvanic vestibular stimulation (galvanic-VEMP) evaluates the motor spinal cord and identifies subclinical myelopathies. We used galvanic-VEMP to compare spinal cord function in individuals infected with human T-cell lymphotropic virus type 1 (HTLV-1) from asymptomatic status to HTLV-1-associated myelopathy (HAM).

Methodology/principal Findings: This cross-sectional study with 122 individuals included 26 HTLV-1-asymptomatic carriers, 26 individuals with possible HAM, 25 individuals with HAM, and 45 HTLV-1-seronegative individuals (controls).