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In the developing brain, groups of neurons organize into functional circuits that direct diverse behaviors. One such behavior is the evolutionarily conserved acoustic startle response, which in zebrafish is mediated by a well-defined hindbrain circuit. While numerous molecular pathways that guide neurons to their synaptic partners have been identified, it is unclear if and to what extent distinct neuron populations in the startle circuit utilize shared molecular pathways to ensure coordinated development. Here, we show that the planar cell polarity (PCP)-associated atypical cadherins Celsr3 and Celsr2, as well as the Celsr binding partner Frizzled 3a/Fzd3a, are critical for axon guidance of two neuron types that form synapses with each other: the command-like neuron Mauthner cells that drive the acoustic startle escape response, and spiral fiber neurons which provide excitatory input to Mauthner cells. We find that Mauthner axon growth towards synaptic targets is vital for Mauthner survival. We also demonstrate that symmetric spiral fiber input to Mauthner cells is critical for escape direction, which is necessary to respond to directional threats. Moreover, we identify distinct roles for Celsr3 and Celsr2, as Celsr3 is required for startle circuit development while Celsr2 is dispensable, though Celsr2 can partially compensate for loss of Celsr3 in Mauthner cells. This contrasts with facial branchiomotor neuron migration in the hindbrain, which requires Celsr2 while we find that Celsr3 is dispensable. Combined, our data uncover critical and distinct roles for individual PCP components during assembly of the acoustic startle hindbrain circuit. Author summary: The assembly of neuronal circuits that drive behavior requires coordination of molecular pathways that govern neuron development and connectivity. Disruption of circuit development can lead to behavioral dysfunction, but understanding how circuits develop in vivo, especially in the immensely complex human brain, poses a significant challenge. Here, we leverage a well-characterized circuit driving a conserved protective behavior, the acoustic startle response, in the developing zebrafish to investigate molecular pathways driving circuit assembly. We discovered that proteins in the planar cell polarity (PCP) pathway are critical for development of two neuron types in the startle hindbrain circuit: the large paired "Mauthner neurons," which mediate the acoustic startle fast escape, and a group of specialized Mauthner-activating "spiral fiber neurons." We found that the PCP atypical cadherin Celsr3 guides Mauthner axon growth towards and into the spinal cord, where Mauthner axons form connections with motor neurons essential for the startle response. Additionally, we uncovered unique and overlapping roles for Celsr3 and the related Celsr2 protein in hindbrain circuit development, shedding light on their specific functions in neurodevelopment. Overall, our findings in zebrafish illustrate how the conserved PCP pathway orchestrates circuit assembly and influences behavior. [ABSTRACT FROM AUTHOR]

Neonicotinoids are the most widely used class of insecticides in the United States (U.S.). and the world. Consistent with their high use and persistence, neonicotinoids are often found contaminating drinking water and food. They are also detected in human urine, breast milk, amniotic and cerebrospinal fluids, as well as the brains of treated rodents. Neonicotinoids were once thought to pose little neurotoxic risk to humans, but a growing body of research challenges that assumption. In this study we provide the first comprehensive assessment of unpublished rodent developmental neurotoxicity (DNT) studies on five neonicotinoids that were submitted to the U.S. Environmental Protection Agency (EPA) by neonicotinoid manufacturers. Groups of female rats were administered three different doses of a neonicotinoid during pregnancy and lactation, and their offspring subjected to various neurological tests and brain measurements. We identified nicotine-like effects such as reduced brain size, indicative of neuronal cell loss. Statistically significant shrinkage of brain tissue was observed in high-dose offspring for five neonicotinoids: acetamiprid, clothianidin, imidacloprid, thiacloprid, and thiamethoxam. Two brain regions reduced in the rodent studies-the corpus callosum and caudateputa mentend to be smaller in people diagnosed with attention-deficit hyperactivity disorder (ADHD), and in children of mothers who smoked during pregnancy, suggesting a possible link between perinatal neonicotinoid exposure and ADHD. A decreased auditory startle reflex was reported for acetamiprid at all doses and was statistically significant in the mid- and high-dose offspring, and for clothianidin in juvenile high-dose females. No mid- or low-dose brain morphometric data were submitted for acetamiprid, imidacloprid, or thiacloprid. Thiamethoxam mid- and low-dose brain morphometric data were provided to EPA upon request. Only partial mid-dose brain morphometry data were submitted for clothianidin, but no low-dose data. Yet despite this lack of data, EPA concluded that only the high-dose brain morphometric effects were treatment-related-setting the mid-dose as the study's No Observed Adverse Effect Level (NOAEL) or failing to find a definitive NOAEL for acetamiprid, clothianidin, imidacloprid, thiacloprid and thiamethoxam. We found numerous deficiencies in EPA's regulatory oversight and data analyses. EPA dismissed statistically significant adverse effects, accepted substandard DNT studies despite lack of valid positive control data, and allowed neonicotinoid registrants to unduly influence agency decision-making. We conclude that perinatal exposure to neonicotinoids and their metabolites induces adverse, nicotine-like neurotoxic effects in rodent bioassays, and that the exposure limits set by EPA for human exposure are either not protective or not supported by available neurotoxicity data. We propose regulatory changes to empower EPA to better protect public health from developmental neurotoxins like neonicotinoids. [ABSTRACT FROM AUTHOR]

Introduction Cornelia de Lange Syndrome (CdLS) is a genetic disorder in which individuals may present sensorineural and/or conductive hearing loss, and the results of behavioral auditory assessments are not accurate. Objective To characterize the audiological profile of individuals with CdLS through behavioral, electroacoustic, and electrophysiological audiological assessments. Methods The study included 13 individuals of both sexes, aged between 3 and 26 years, with diagnoses confirmed through genetic studies. The following procedures were performed: medical history survey, otoscopy (pure-tone audiometry [PTA], speech audiometry, and acoustic immittance measures), and auditory brainstem response (ABR). Results In total 62.50% of the participants who underwent PTA had abnormal results (all of which were mild), with a predominance of bilateral conductive hearing loss (60%). Regarding tympanometry, 76.93% had abnormal results, most frequently type B (85.72% on the right and 88.89% on the left ear). Acoustic reflexes showed results compatible with tympanometry changes. Changes in ABR latency values compatible with middle-ear impairment were found in 8 of them (66.66%) – 3 had bilateral (37.50%), and 5 had unilateral impairments (62.50%). Conclusion Mild hearing loss was identified in 62.5% of the individuals with CdLS who underwent the behavioral audiological assessment. In the acoustic immittance measures, 76.9% of the participants presented a tympanometry curve characteristic of middle-ear changes. Acoustic reflexes were absent in 84.6% of the subjects. In the ABR, no changes were identified in auditory pathway integrity. On the other hand, changes in the absolute latency values were found, which are characteristic of conductive hearing loss. [ABSTRACT FROM AUTHOR]

Yakshagana is an India's traditional folk theatre musical dance drama. The purpose of the study is to profile audiological characteristics and document hearing-related symptoms in Yakshagana artists. A cross-sectional study was performed on 96 Yakshagana artists. Participants' demographic data were captured, and audiological evaluations, including high frequency audiometry (HFA), tympanometry, acoustic reflex threshold and transient evoked otoacoustic emission (TEOAE), were performed. The majority of the individuals had minimal and mild hearing loss. The mean scores of pure tone thresholds were greater at 4 kHz and 8 kHz. The majority of the HFA thresholds at 10 kHz, 12.5 kHz, and 16 kHz indicated no responses, which can be accredited to the fact that noise-induced hearing loss (NIHL) first affects the higher frequencies. TEOAE analysis showed a greater percentage of failures in the higher frequencies, particularly at 3 and 4 kHz in both ears, which can be an indicator of bilateral cochlear damage. These findings indicate that Yakshagana artists are at risk of hearing loss due to noise exposure. Hearing evaluation and regular monitoring of hearing thresholds is advisable for this population as it can impact their careers. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of previous occupational noise exposure in older adults with hearing loss on (1) audiometric configuration and acoustic reflex (AR) thresholds and (2) self-reported hearing abilities and hearing aid (HA) effectiveness. Design: A prospective observational study. Study sample: The study included 1176 adults (≥60 years) with bilateral sensorineural hearing loss. Pure-tone audiometry, AR thresholds, and responses to the abbreviated version of the Speech, Spatial, and Qualities of Hearing Scale (SSQ12) and the International Outcome Inventory for Hearing Aids (IOI-HA) questionnaire were obtained, along with information about previous occupational noise exposure. Results: Greater occupational noise exposure was associated with a higher prevalence of steeply sloping audiograms in men and women and a 0.32 (95% CI: −0.57; −0.06) scale points lower mean SSQ12 total score among noise-exposed men. AR thresholds did not show a significant relation to noise-exposure status, but hearing thresholds at a given frequency were related to elevated AR thresholds at the same frequency. Conclusions: A noise exposure history is linked to steeper audiograms in older adults with hearing loss as well as to poorer self-reported hearing abilities in noise-exposed men. More attention to older adults with previous noise exposure is warranted in hearing rehabilitation. [ABSTRACT FROM AUTHOR]

Background: In humans, saccular acoustic sensitivity has been confirmed. The aim of this study was to determine the scores of the word-in-noise perception test at the saccular acoustic sensitivity level. Methodology: In this randomized clinical trial study, 101 participants in the age group of 14 to 25 years with normal hearing and middle ear function, detectable vestibular evoked myogenic potentials (VEMP), normal states of mental health, and night sleep were investigated. The scores of word-in-noise perception and word-in-noise discrimination tests were evaluated for each person at two intensity levels, most comfortable level (MCL) and saccular acoustic sensitivity. Mann-Whitney was used for the multiple comparisons. Results: There was a significant difference between the scores of the word-in-noise perception test at MCL and saccular acoustic sensitivity (U = 3971.50, Z = − 2.10, p' = 0.04), and also between the scores of the word-in-noise discrimination test at the MCL compared to saccular acoustic sensitivity (U = 399.89, Z = − 2.49, p' = 0.04). Word-in-noise discrimination scores in MCL (U = 3484.00, Z = -3.72, p' = 0.00) and saccular acoustic sensitivity (U = 705.50, Z = − 3.78, p' = 0.00) were higher than word-in-noise perception. Conclusions: Word-in-noise perception and word-in-noise discrimination scores are higher in saccular acoustic sensitivity level than MCL, suggesting that the vestibular system participates in loud speech perception. Also, in people with normal hearing thresholds, word-in-noise perception scores will be lower than word-in-noise discrimination scores for both loud and common intensity levels. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study is to investigate the age-related changes of the Contralateral Acoustic Reflex Suppression (CARS) test in individuals with normal hearing and to provide age-related normal values. Method: The study included 66 individuals aged 18-65 years. The participants were divided into three age groups, respectively, 18-30 years, 31-45 years, and 46--65 years. Acoustic reflex threshold and acoustic reflex amplitude measurements were performed at frequencies of 500, 1000, and 2000 Hz in the presence and absence of suppressive noise from the contralateral ear. Results: In the comparison of suppression amounts according to age groups, the highest suppression amount at all frequencies was observed in the 18-30 years age group. Conclusions: It is known that changes in the function of the efferent hearing system occur due to aging. In the CARS test, a decrease in the amount of suppression produced by the efferent system has been observed due to aging. [ABSTRACT FROM AUTHOR]

Objective: Hearing disorders are common among music professionals, as they are frequently exposed to sound levels exceeding 100 dB(A). By assessing auditory fatigue, situations that are deleterious for hearing could be identified, allowing the deployment of preventive measures before permanent impairment occurs. However, little is known about the factors contributing to auditory fatigue. The objective is to determine the exposure parameters most influencing auditory fatigue during occupational exposure to amplified music. Design: Auditory fatigue was defined as variations of both pure tone auditory (ΔPTA) and efferent reflex thresholds (ΔER) during the workday. Noise exposure was monitored and information on the volunteers was gathered using a questionnaire. Study sample: The population consisted of 43 adult volunteers exposed to amplified music (sound, light or stage technicians, security agents, barmen) and 24 unexposed administrative agents. Results: ΔPTA and ΔER were positively correlated with the energy of noise exposure and its stability over time, i.e a steady noise tends to create more auditory fatigue. Conclusion: In addition to a global decrease of music levels and a systematic use of hearing protection, our results advocate for the provision of quiet periods within noise exposures as they reduce auditory fatigue accumulation and long-term risks for hearing. [ABSTRACT FROM AUTHOR]

Rodent models of tinnitus are commonly used to study its mechanisms and potential treatments. Tinnitus can be identified by changes in the gap-induced prepulse inhibition of the acoustic startle (GPIAS), most commonly by using pressure detectors to measure the whole-body startle (WBS). Unfortunately, the WBS habituates quickly, the measuring system can introduce mechanical oscillations and the response shows considerable variability. We have instead used a motion tracking system to measure the localized motion of small reflective markers in response to an acoustic startle reflex in guinea pigs and mice. For guinea pigs, the pinna had the largest responses both in terms of displacement between pairs of markers and in terms of the speed of the reflex movement. Smaller, but still reliable responses were observed with markers on the thorax, abdomen and back. The peak speed of the pinna reflex was the most sensitive measure for calculating GPIAS in the guinea pig. Recording the pinna reflex in mice proved impractical due to removal of the markers during grooming. However, recordings from their back and tail allowed us to measure the peak speed and the twitch amplitude (area under curve) of reflex responses and both analysis methods showed robust GPIAS. When mice were administered high doses of sodium salicylate, which induces tinnitus in humans, there was a significant reduction in GPIAS, consistent with the presence of tinnitus. Thus, measurement of the peak speed or twitch amplitude of pinna, back and tail markers provides a reliable assessment of tinnitus in rodents. [ABSTRACT FROM AUTHOR]

Objective: The study aimed to compare ipsilateral and contralateral electrically evoked stapedial reflex thresholds in children with a unilateral cochlear implant surgically implanted either through Veria or posterior tympanotomy approaches. Methods: Forty-nine children using cochlear implants were studied, of whom 27 underwent the Veria approach and 22 underwent the posterior tympanotomy approach. The electrically evoked stapedius reflex thresholds were measured ipsilaterally and contralaterally by stimulating four equally spaced electrodes. Results: The ipsilateral electrically evoked stapedius reflex threshold was absent in all four electrodes in the children implanted using the Veria approach. However, the ipsilateral electrically evoked stapedius reflex threshold was present in 70 per cent of the children implanted using the posterior tympanotomy approach. The contralateral electrically evoked stapedius reflex threshold was present in most of the children for both surgical approaches. Conclusion: The presence of the ipsilateral electrically evoked stapedius reflex threshold varies depending on the surgical technique used for cochlear implantation. However, contralateral reflexes are present in the majority of children using cochlear implants, irrespective of the surgical approach. [ABSTRACT FROM AUTHOR]

The study investigated the relationship between the strength of the medial olivocochlear reflex (measured via contralateral inhibition of otoacoustic emissions) and speech perception in noise (obtained from behavioural identification task) through meta-analyses. A systematic review and random-effects meta-analysis of studies investigating the relationship in neurotypical adults was performed. The systematic search (in PubMed, Scopus, Science Direct and Google Scholar databases) revealed 21 eligible studies, which were critically appraised using the NIH tool for Observational Cohort and Cross-Sectional Studies. Meta-analysis was performed on 17 studies (374 participants) with fair to good quality. The results revealed that the medial olivocochlear reflex accounts for less than 1% of the variations in speech perception in noise in neurotypical individuals. Sub-group analyses conducted to address a few methodological differences also revealed no discernible association between the two variables. The results reveal no modulatory effect of the medial olivocochlear reflex assessed using contralateral inhibition of otoacoustic emission on the ability to perceive speech in noise. However, more data utilising alternative measures of medial olivocochlear reflex strength is necessary before drawing any conclusions about the role of the medial olivocochlear bundle in speech perception in noise. [ABSTRACT FROM AUTHOR]

Background: This study examined the relationship between behavioural thresholds as measured by pure tone audiometry and electrophysiological thresholds measured by the Auditory Steady-State Response (ASSR) in children with normal hearing and sensorineural hearing loss. Materials and Methods: After being assessed, 45 children of both sexes, ranging in age from 5 to 15, were split into four groups: 10 with moderate to moderately severe sensorineural hearing loss (G2M); 10 with steeply sloping sensorineural hearing loss (G2D); 10 with profound and severe sensorineural hearing loss (G2S); and 15 with normal hearing (G1). ASSR, tympanometry, acoustic reflex testing, pure tone audiometry, and speech audiometry (SRT and SDT) were performed. Results: The electrophysiological maximum in the group with normal hearing thresholds varied from 19 to 27 dB NA. The correlation in the group with moderate to moderately severe hearing loss was 0.42–0.74. The correlation in the steeply sloping hearing loss group was 0.68–0.94. The correlation in the group of people with profound and severe hearing loss was 0.59–0.86. The normal hearing group's mean differences in ASSR threshold and audiometric threshold ranged from −0.3 to 12 dB, in the moderate and moderately severe hearing loss group from −9 to 2 dB, in the steeply sloping hearing loss group from 1.4 to 7.5 dB, and in the severe and profound hearing loss group from −0.40 to 8.5 dB. Conclusion: As expected, there was no strong relationship between behavioural and electrophysiological thresholds in the group with normal hearing. But in children with hearing loss, there was a strong correlation between electrophysiological and behavioural thresholds; this relationship was especially evident in children with severe and profound hearing loss and those with steeply sloping hearing loss. [ABSTRACT FROM AUTHOR]

Objectives: Acoustic immittancemetry measurement is made using a probe tone or click stimulus at a frequency of 226 Hz, which is included in the audiological test battery. This study aims to compare tympanometric peak pressure (TPP), static acoustic admittance (Ytm), equivalent external ear canal volume (Vea) and tympanometric width (TW) values measured with probe tone and click stimulus at 226 Hz frequency. Design: Measurements were made with a probe tone and click stimulus at frequency of 226 Hz in 60 ears of 30 adult individuals with normal hearing between the ages of 18–26. In the measurements TPP, Ytm, Vea and TW values were determined for both ears. Results: In two different tympanogram measurement results using 226 Hz click stimulus and 226 Hz probe tone were a statistically significant difference was found between Ytm, Vea and TW values in the left ear (p < 0.05) and a statistically significant difference was found between Ytm and Vea values in the right ear (p < 0.05). There was no significant difference between the right ear TPP and TW values, left ear TPP value (p > 0.05). Conclusıon: The current findings show that the comment of right and left ear tympanogram results should be evaluated according to two different measurement results using 226 Hz click stimulus and 226 Hz probe tone. [ABSTRACT FROM AUTHOR]

Background: Idiopathic intracranial hypertension (IIH) can affect both hearing and balance due to increased inner ear pressure. Aims/Objectives: This study aimed to evaluate the impact of increased inner ear pressure on hearing and balance in patients with IIH using auditory and vestibular tests. Material and Methods: Twenty-four IIH patients and 28 healthy controls underwent oVEMP, pure tone audiometry, tympanometry, and acoustic reflex tests pre-lumbar punctures. IIH patients received acetazolamide. Pre- and post-treatment results, tinnitus, and vertigo scores were compared. Post-treatment oVEMP and audiometry results were compared between groups. Results: Pre-treatment oVEMP showed a significant left N1 latency difference (p = 0.049). Post-treatment, left ear amplitude (p = 0.035) and both ear amplitude ratios (p = 0.044 and p = 0.047) increased significantly. Audiometry had no significant changes (p < 0.05). Tinnitus and vertigo scores decreased significantly (p ≤ 0.001). Conclusion: Prolonged oVEMP latency suggests IIH may impact the brain stem and vestibular nerve, while increased amplitude values indicate peripheral vestibular involvement. IIH affects hearing across all frequencies, especially at 4000 Hz, impacting both hearing and balance. Significance: Understanding the effects of IIH on auditory and vestibular functions can guide effective treatments, improving quality of life for patients by addressing both hearing and balance issues. [ABSTRACT FROM AUTHOR]

Objective: This study aims to evaluate efferent auditory system by medial olivocochlear (MOC) reflex on patients with multiple sclerosis (MS). Material and Methods: 53 participants with normal hearing (30 MS patients and 23 control group) was involved in the study. MS patients divided in two groups as “patients without definable brainstem lesion (Group 1, n=15)” and “patients with definable brainstem lesion (Group 2, n=15)” by cranial magnetic resonance imaging. All participants had pure tone audiometry, acoustic reflex test, transient evoked otoacoustic emission (TEOAE) amplitude measurements [with 80 ±4 dB peak equivalent sound pressure level (peSPL) click stimulus]. MOC pathway evaluated with contralateral suppresion measurement is made by 65 dB peSPL linear click stimulus with 50 dB SPL white noise on contralateral ear. Results: TEOAE signal to noise-ration (SNR) amplitudes on right ear on 2,000 and 2,800 Hz are found to be higher on control group than Group 2 (p<0.05). In the left ear, SNR amplitudes with 4,000 Hz in Group 1 and control group is higher than Group 2 (p<0.05). In terms of MOC reflex positivity ratio; there is no statistically meaningful difference (p>0.05). Mean suppresion in the control group’s left ears found to be higher than Group 2 left ears (p<0.05). Conclusion: Our results demonstrated TEOAE SNR amplitude reduction in MS patients with brainstem involvement. Even though no MOC reflex positivity ratio difference was found between groups, control groups suppression level on the left side found to be superior to Group 2. In MS patients, because of brainstem involvement; TEAOE SNR amplitudes and suppresion levels may decrease. [ABSTRACT FROM AUTHOR]

Background: Hearing loss (HL) is a common congenital disease present at birth, happening in approximately one to three of every 1000 healthy newborns. Evoked otoacoustic emission (OAE) is extremely useful in infant hearing screening. Tympanometry is a test that measures the changes of the acoustic impedance (AI) of the tympanic ossicular system (TOS). Objective: This study aimed to evaluate the role of high-frequency tympanometry (HFT) in neonatal hearing screening (NHS), and to study the prevalence of HL in a sample of newborns. Patients and methods: This Cross-sectional study included 100 neonates who were tested in three stages, first stage was screening by transient evoked otoacouastic emissions (TEOAE) and HFT at primary health care centers, second and third stages was audiological diagnosis at the Audiology Unit of Mansoura New General Hospital. Results: Tympanometry (1000Hz) was with type A in 152 ears and type B in 48 ears. Ipsilateral acoustic reflexes were present in 146 ears and absent in 54 ears. In 2nd step, tympanometry (1000Hz) was type A in 29 right ears and 29 in left ears and type B in 8 right ears and 8 left ears. In 3rd step, tympanometry (1000Hz) with type A was in 22 ears and type B in 4 ears. Normal click auditory brainstem response (ABR) threshold was found in 17 ears and abnormal click ABR threshold was found in 9 ears. Conclusion: 1000 Hz tympanometry has to be a component of the NHS test battery. The HFT has to be considered for NHS programs to detect the middle ear pathological conditions in infants. [ABSTRACT FROM AUTHOR]

BACKGROUND: The internal perception of sound in the absence of external auditory stimulation is what is meant to describe the condition known as tinnitus. Tinnitus is one of three Otoneurologic manifestations, along with sensorineural hearing loss and dizziness, which are frequently the primary individuals' complaint. Tinnitus is the most common of these three symptoms. AIM: Determination of relationship between vestibular function and tinnitus in normal hearing subjects METHODS: Thirty subjects complained of tinnitus without hearing loss were included, and were divided into 2 groups, group 1: included 40 tinnitus ear, and group 2; included 20 non tinnitus ear. RESULTS In terms of pure tone threshold, assessment SRT, WDS%, acoustic reflexes parameters, cervical vestibular evoked myogenic potential (cVEMPs) latencies, and peak amplitude, there was no statistically difference between the tinnitus and non-tinnitus groups. There was a statistically in-significant variation between the amplitude ratio of caloric response and sex, there was also statistically in-significant relation between tinnitus duration and vestibular function (P13 and N23 latency). CONCLUSIONS: We concluded that; Tinnitus have a link with an aberrant caloric response. [ABSTRACT FROM AUTHOR]

Background: A fifteen-week-old infant was presented for chiropractic care with the mother listing concerns that the infant could not participate in life the way she should. The infant was behind on all her milestones, was showing head asymmetry, and inability to to lift her head or respond to caregivers the way she should. Intervention: The infant commenced a course of chiropractic care, during which the patient was adjusted using the Diversified technique, with assistance from the baby drop piece, vibrations, hands-on adjusting, Sacro-occipital technique basics and cranial adjusting. Dural support was used, along with Activator methods and logan, all of which were modified for age-appropriateness. Outcomes: In addition to significant improvements in her subluxations, the infant was able to make strong leaps forward in tone, responses and reflex integration. She was able to fully regain age-appropriate developmental milestones and undertake strength and skill-based tests appropriate to her age. Parents remarked that she was like a completely different child. Conclusion: This case report illustrates an instance in which a child's developmental trajectory was significantly changed by chiropractic care. Given the outcomes of this case, the impact of chiropractic care on infant development is warranted. [ABSTRACT FROM AUTHOR]

The paper considers an implant of the human inner ear as an electroacoustic system. The implant serves to partially restore human hearing by direct impact on the nerve endings of the coil with electrical impulses. Electrical stimulation of the auditory nerve, in turn, leads to auditory sensations. A block diagram of an implant using an ultrasonic communication line between the external and internal parts of the system is selected. A theoretical study of the influence of parameters on the frequency properties and sensitivity of the ultrasonic line of acoustic information transmission was carried out, which is based on a mathematical algorithm that implements the calculation of the sensitivity of the transmission channel depending on the frequency and channel parameters. A multilayer model of the communication line was chosen for calculations, which contains emitting and receiving piezo plates, two protectors to ensure safe contact between the receiving and emitting piezo plates and bio tissue, an intermediate layer of bio tissue, two dampers that are adjacent to the emitter and receiver, respectively. At the same time, it is considered that the dampers have limited dimensions. As a result, the influence of individual design parameters of the transmission line on the maximum sensitivity of the line and its frequency characteristic is theoretically researched. [ABSTRACT FROM AUTHOR]

The present study attempted to understand the association between Auditory neuropathy spectrum disorder (ANSD) and Sickle cell anemia (SCA) and to recognize possible causative factors for the presence of ANSD in SCA individuals. Two cases, 24 years male and 17years female with a laboratory-confirmed diagnosis of Sickle cell anemia underwent detailed audiological evaluation i.e., pure tone audiometry, speech audiometry, immittance audiometry, otoacoustic emission, and auditory brainstem responses. Audiological evaluation revealed a bilateral moderate low-frequency sensorineural hearing loss in male and bilateral moderately severe sensorineural Hearing loss in female case with elevated Speech Recognition Threshold and poor Speech Identification Scores. 'A' type tympanogram with the absence of Acoustic reflexes and the presence of Otoacoustic emission with no distinct and reproducible peak V in Auditory Brainstem Response (ABR) at 90 dBnHL with the presence of ringing cochlear microphonics on polarity reversal collectively indicating bilateral ANSD in both cases. ANSD and SCA are reported to have a genetic basis of etiology. There might be possibilities that one genetic condition may be common in manifesting both conditions or one genetic condition can cause the presence of another genetic condition or can exaggerate the evolution of another genetic condition. Also, abnormal ABR findings indicate the possibility of neuropathological involvement in isolation or in combination with genetic abnormalities that need detailed investigation to understand non-genetic causative factors. Thus, paved the path for further research in this line and might provide better rehabilitative options. [ABSTRACT FROM AUTHOR]

Feldspar vein-intrusive metagabbro is a special geological structure, and different stress angles have an important influence on the fracture mode and deformation characteristics of metagabbro. A Brazilian splitting test on feldspar vein-intrusive metagabbro was performed using three distinct stress angles (0°, 45°, and 90°), and acoustic emission signals and strain characteristics were monitored synchronously during the test. The results showed that the damage pattern of the feldspar vein-intrusive metagabbro was related to the feldspar mineral perforation damage on the main rupture surface. With the increase in stress angle, the percentage of high peak frequency increased gradually. The phenomenon of strain lagging stress appeared in the rock samples before the peak damage. The feldspar minerals played a controlling role in the expansion of microcracks in the feldspar vein-intrusive metagabbro. Significant differences in the local deformation coordination of rocks under different stress angles were observed. The deformation coordination of rock samples with a stress angle of 0° was much lower than that of other rock samples. This study is of great significance for the understanding of the deformation and damage laws of similar geological structures and also provides an important theoretical basis for the stability of deep chambers. [ABSTRACT FROM AUTHOR]

Several viruses are known to have a negative impact on hearing health. The global prevalence of COVID-19 means that it is crucial to understand whether and how SARS-CoV2 affects hearing. Evidence to date is mixed, with studies frequently exhibiting limitations in the methodological approaches used or the populations sampled, leading to a substantial risk of bias. This study addressed many of these limitations. A comprehensive battery of measures was administered, including lab-based behavioural and physiological measures, as well as self-report instruments. Performance was thoroughly assessed across the auditory system, including measures of cochlear function, neural function and auditory perception. Hypotheses and analyses were pre-registered. Participants who were hospitalised as a result of COVID-19 (n = 57) were compared with a well-matched control group (n = 40) who had also been hospitalised but had never had COVID-19. We find no evidence to support the hypothesis that COVID-19 is associated with deficits in auditory function on any auditory test measure. Of all the confirmatory analyses, only the self-report measure of hearing decline indicated any difference between groups. Results do not support the hypothesis that COVID-19 infection has a significant long-term impact on the auditory system. [ABSTRACT FROM AUTHOR]

The purpose of this pilot study was to evaluate the magnitude of the medial olivocochlear reflex (MOCR) estimated by the reduction in tone-burst evoked otoacoustic emissions (TBOAEs) measured at three levels and at three frequencies in response to fixed contralateral white noise. Results were compared with commonly used click-evoked otoacoustic emissions (CEOAEs). TBOAEs and CEOAEs, with and without contralateral 60 dB SPL white noise, were measured in response to stimulation at 55, 65, and 75 dB peSPL. In each subject, the set of measurements was performed twice. Of particular interest were the MOCR and its repeatability. 15 normally hearing persons (13 women, average age 32.3 years, SD = 8.1). For both CEOAE and TBOAEs, the reliability of the MOCR was much better for broadband measurements than for half-octave-band filtered estimates. At the same time, the reliability of MOCR in half-octave bands was higher for TBOAEs than for CEOAEs, especially at 2 and 4 kHz. For general applications where broadband MOCR is of interest, the highest magnitude and reliability is provided by CEOAEs. However, TBOAEs may be better if a particular frequency band is of interest. [ABSTRACT FROM AUTHOR]

Background: Otosclerosis is one of the leading causes of conductive hearing loss with an intact tympanic membrane in adults. The stapedius tendon is routinely transected during stapes surgery. This study aimed to evaluate the success rates of stapedectomy with preservation of the stapedial muscle tendon compared to stapedectomy without preservation of the stapedial muscle tendon in the operative management of otosclerosis. Methods: This is a retrospective study. It was conducted in the Otorhinolaryngology Department, Faculty of Medicine, Zagazig University, from October 2018 to January 2021. The sample size was 36 cases, arranged into two groups: the first group with preservation, and the second group with a cut of the stapedial tendon. The size of each group is 18 cases. Results: There was no significant difference between both groups in hearing improvement, but there was a significant difference between both groups in post-operative tinnitus improvement and acoustic reflex preservation. Conclusions: Preservation of the stapedial tendon in the surgical treatment of otosclerosis is associated with improvement in functional outcomes as well as providing the patient with a stapedial reflex that has a primary protective effect against strong acoustic stimuli. [ABSTRACT FROM AUTHOR]

Introduction: Chronic adolescent stress profoundly affects prefrontal cortical networks regulating top‐down behavior control. However, the neurobiological pathways contributing to stress‐induced alterations in the brain and behavior remain largely unknown. Chronic stress influences brain growth factors and immune responses, which may, in turn, disrupt the maturation and function of prefrontal cortical networks. The tumor necrosis factor alpha‐converting enzyme/a disintegrin and metalloproteinase 17 (TACE/ADAM17) is a sheddase with essential functions in brain maturation, behavior, and inflammatory responses. This study aimed to determine the impact of stress on the prefrontal cortex and whether TACE/ADAM17 plays a role in these responses. Methods: We used a Lewis rat model that incorporates critical elements of chronic psychosocial stress, such as uncontrollability, unpredictability, lack of social support, and re‐experiencing of trauma. Results: Chronic stress during adolescence reduced the acoustic startle reflex and social interactions while increasing extracellular free water content and TACE/ADAM17 mRNA levels in the medial prefrontal cortex. Chronic stress altered various ethological behavioral domains in the observation home cages (decreased ingestive behaviors and increased walking, grooming, and rearing behaviors). A group of rats was injected intracerebrally either with a novel Accell™ SMARTpool TACE/ADAM17 siRNA or a corresponding siRNA vehicle (control). The RNAscope Multiplex Fluorescent v2 Assay was used to visualize mRNA expression. Automated puncta quantification and analyses demonstrated that TACE/ADAM17 siRNA administration reduced TACE/ADAM17 mRNA levels in the medial prefrontal cortex (59% reduction relative to control). We found that the rats that received prefrontal cortical TACE/ADAM17 siRNA administration exhibited altered eating patterns (e.g., increased food intake and time in the feeding zone during the light cycle). Conclusion: This study supports that the prefrontal cortex is sensitive to adolescent chronic stress and suggests that TACE/ADAM17 may be involved in the brain responses to stress. [ABSTRACT FROM AUTHOR]

Background: Acoustic telemetry is an important tool to study the movement of aquatic animals. However, studies have focussed on particular groups of easily tagged species. The development of effective tagging methods for ecologically important benthic species, such as sea stars, remains a challenge due to autotomy and their remarkable capacity to expel any foreign material. We tested three methods to surgically attach acoustic transmitters to the common sea star Asterias rubens; two methods attached the tag to the aboral side of the central body and the third attached the transmitter to the aboral side of an arm. Laboratory experiments evaluated each method in terms of survivability, tag retention, associated injuries, and changes in feeding behaviour and physical condition. Results: Laboratory results were highly variable; however, all tagging methods caused significant injury to the epidermis and deeper tissue around the attachment site over periods greater than 4 weeks. Attaching a tag by horizontally piercing the central body (method HPC) had minimal effects in the short-term (2–3 weeks) and this method was used for a pilot tagging study in the field, where 10 sea stars were tagged and placed within an existing acoustic telemetry array. Although, the interpretation of field data was challenging due to the characteristic slow movement of sea stars, movements of a similar magnitude to previous studies were identified during the 2–4 weeks after sea stars were tagged and released. However, this apparent period of tagging success was followed by a reduction in movement that, when viewed in conjunction with laboratory results, potentially indicated a deterioration in the sea stars' physical condition. Conclusions: While acoustic telemetry continues to provide novel insights into the ecology of a wide variety of marine species, species-specific effects of tagging should be evaluated before starting field studies. If the autonomous study of benthic movement is to expand beyond hard-bodied macroinvertebrates current methodological and analytical challenges must be addressed. [ABSTRACT FROM AUTHOR]

Introduction: The acoustic reflex is the active response of the middle ear to loud sounds, altering the mechanical transfer function of the acoustic energy into the inner ear. Our goal was to observe the effect of the acoustic reflex on the tympanic membrane by identifying a significant nonlinear increase in membrane oscillations. Methods: By using interferometric spectrally encoded endoscopy, we record the membrane oscillations over time in response to a loud, 200-ms-long acoustic stimulus. Results: A gradual reflex activation is measured between approximately 40 and 100 ms, manifested as a linear 42% increase in the umbo oscillation amplitude. Conclusion: The measured oscillations correlate well with those expected from a mechanical model of a damped harmonic oscillator, and the results of this work demonstrate the potential of interferometric spectrally encoded endoscopy to observe unique dynamical processes in the tympanic membrane and in the middle ear. [ABSTRACT FROM AUTHOR]

Fronting of the vowels /u, ʊ, o/ is observed throughout most North American English varieties, but has been analyzed mainly in terms of acoustics rather than articulation. Because an increase in F2, the acoustic correlate of vowel fronting, can be the result of any gesture that shortens the front cavity of the vocal tract, acoustic data alone do not reveal the combination of tongue fronting and/or lip unrounding that speakers use to produce fronted vowels. It is furthermore unresolved to what extent the articulation of fronted back vowels varies according to consonantal context and how the tongue and lips contribute to the F2 trajectory throughout the vowel. This paper presents articulatory and acoustic data on fronted back vowels from two varieties of American English: coastal Southern California and South Carolina. Through analysis of dynamic acoustic, ultrasound, and lip video data, it is shown that speakers of both varieties produce fronted /u, ʊ, o/ with rounded lips, and that high F2 observed for these vowels is associated with a front-central tongue position rather than unrounded lips. Examination of time-varying formant trajectories and articulatory configurations shows that the degree of vowel-internal F2 change is predominantly determined by coarticulatory influence of the coda. [ABSTRACT FROM AUTHOR]

Background: Sleep deprivation (SD) impairs pre-stimulus inhibition, but the effect of quetiapine (QET) remains largely unknown. Objective: This study aimed to investigate the behavioral and cognitive effects of QET in both naïve and sleep-deprived rats. Materials and methods: Seven groups (n = 49) of male Wistar Albino rats were used in this study. SD was performed using the modified multiple platform technique in a water tank for 72 h. Our study consists of two experiments investigating the effect of QET on pre-pulse inhibition (PPI) of the acoustic startle reflex. The first experiment tested the effect of short- and long-term administration of QET on PPI response in non-sleeping (NSD) rats. The second experiment used 72 h REM sleep deprivation as a model for SD-induced impairment of the PPI response. Here, we tested the effect of QET on the % PPI of SD rats by short- and long-term intraperitoneal injection at the last 90 min of sleep SD and immediately subsequently tested for PPI. Results: 72 h SD impaired PPI, reduced startle amplitude, and attenuated the PPI% at + 4 dB, + 8 dB, and + 16 dB prepulse intensities. 10 mg/kg short and long-term QET administration completely improved sensorimotor gating deficit, increased startle amplitude, and restored the impaired PPI% at + 4 dB, + 8 dB, and + 16 dB after 72 h SD in rats. Conclusion: Our results showed short- and long-term administration of QET improved sensorimotor gating deficit in 72 h SD. Further research is required for the etiology of insomnia and the dose-related behavioral effects of QET. [ABSTRACT FROM AUTHOR]

Anuran communication is largely based on acoustic signals, but different sensory modes are also widespread, including visual communication using body color traits as a way of signaling. The Brazilian treefrog, Boana albomarginata, has a complex behavioral repertoire presenting several call types and performing gestures as visual signals. This species has a greenish body color with orange patches on the flanks and thighs. These patches become visible when males are in a calling posture or performing visual signals such as leg kicking and limb lifting, suggesting that they might use the patches as visual cues. We sampled seven populations, using call recordings and photographs to access males call and color traits. We demonstrate that there is variation in color and call properties across populations. Additionally, we observe variation in the relationship between color traits and call properties in different populations, revealing that only two populations exhibit a significant correlation between color and call traits. Further, while call properties and color traits were not related with individual body size, they were associated with body condition. The results indicate a universal pattern across populations for call properties, wherein males in better condition consistently displayed lower-pitched calls, longer calls, and shorter intervals between calls. Regarding color traits, males in better condition in four out of the seven evaluated populations exhibited larger orange patch sizes, lower orange hue values, and higher hue contrasts. Although we observed some level of relation among color, call, and body traits, there is not a universal pattern across all populations. Significance statement: Animal social interactions are mediated by signals transmitted through different sensory modes (i.e., acoustic, chemical, tactile, and visual), and more than one of these modalities can compose the behavioral repertoire of one species. Using photographs and acoustic recordings of Boana albomarginata males in natural environments, we documented geographic variation in both signals, call and color, and investigated their potential to convey individual body size and condition. Our findings reveal that both signals were correlated with individual body condition. In addition, color traits were associated with call properties in some populations. [ABSTRACT FROM AUTHOR]

The clinical audiology test battery often involves playing physically simple sounds with questionable ecological value to the listener. In this technical report, we revisit how valid this approach is using an automated, involuntary auditory response; the acoustic reflex threshold (ART). The ART was estimated four times in each individual in a quasi-random ordering of task conditions. The baseline condition (referred to as Neutral) measured the ART following a standard clinical practice. Three experimental conditions were then used in which a secondary task was performed whilst the reflex was measured: auditory attention, auditory distraction and visual distraction tasks. Thirty-eight participants (27 males) with a mean age of 23 years were tested. All participants were audiometrically healthy. The ART was elevated when a visual task was performed at the same time as the measurements were taken. Performing an auditory task did not affect the ART. These data indicate that simple audiometric measures widely used in the clinic, can be affected by central, non-auditory processes even in healthy, normal-hearing volunteers. The role of cognition and attention on auditory responses will become ever more important in the coming years. [ABSTRACT FROM AUTHOR]

The ability of individuals with visual impairment to recognize an obstacle by hearing is called "obstacle sense". This ability is facilitated while they are moving, though the exact reason remains unknown. This study aims to clarify which acoustical factors may contribute to obstacle sense, especially obstacle distance perception. First, we conducted a comparative experiment regarding obstacle distance localization by individuals who are blind (N = 5, five men with blindness aged 22–42 (average: 29.8)) while they were standing and walking. The results indicate that the localized distance was more accurate while walking than while standing. Subsequently, the head rotation angle while walking and acoustic characteristics with respect to obstacle distance and head rotation angle were investigated. The peaks of the absolute head rotation angle during walking ranged from 2.78° to 11.11° (average: 6.55°, S.D.: 2.05°). Regarding acoustic characteristics, acoustic coloration occurred, and spectral interaural differences and interaural intensity differences were observed in the blind participants (N = 4, four men including two blind and two control sighted persons aged 25–38 (average: 30.8)). To determine which acoustic factors contribute, we examined the threshold of changes for interaural differences in time (ITD) and intensity (IID) (N = 11, seven men and four women with blindness aged 21–35 (average: 27.4)), as well as coloration (ICD) (N = 6, seven men and a woman with blindness aged 21–38 (average: 29.9))—depending on the head rotation. Notably, ITD and IID thresholds were 86.2 μs and 1.28 dB; the corresponding head rotation angles were 23.5° and 9.17°, respectively. The angle of the ICD threshold was 6.30° on average. Consequently, IID might be a contributing factor and ICD can be utilized as the cue facilitating the obstacle distance perception while walking. [ABSTRACT FROM AUTHOR]

Background & Objective: Vitiligo as an acquired disorder is caused by the gradual loss of functional melanocytes. Aiming to assess whether vitiligo is associated with hearing loss. Materials & Methods: A population based case-control study (case, n=50; control, n=51). The case group included all vitiligo patients referred to public and private clinics in Semnan in March 2021 to October 2021. Then, for each case, one control was selected from the people who did not have any skin disease and had only visited the same center for cosmetic procedures. Audiometric tests including pure tone audiometry (PTA), speech discrimination score (SDS), speech reception threshold (SRT), acoustic reflex (AR) and tympanometry were performed for both case and control groups. Results: The mean of age (±SD) was 31.3 (8.5) and 33.5 (7.9) in two groups. The numbers (%) of women were 32 (64%) and 27 (52.9%); respectively. The result of AR test was normal in 80% of the patients and 92% of the control group; respectively. PTA test result was abnormal in 18 and 2% of cases and controls, respectively. SDS, SRT and Tympanometry Tests were normal in all people of the two groups under investigation. However, the odds of having an abnormal PTA test in vitiligo patients was 10.97 times that of healthy people (OR=10.97; 95% CI: 1.39 – 15.38) (P=0.007). Conclusion: A relationship was observed between vitiligo and hearing loss, so regular hearing checks are recommended in these patients. [ABSTRACT FROM AUTHOR]

Background: It has long been believed that the patulous eustachian tube is a unique but uncommon condition, with an estimated incidence ranging from 0.3 to 6.6% in the general population. Hearing one's own voice and breathing, or autophony and aerophony, are the most common symptoms of PET, along with frequent auditory fullness. Aim: This study is to establish a standardized protocol for the audiological evaluation of patulous Eustachian tube using acoustic reflex decay test during different breathing tasks. Methods: Between January 2022 and December 2022, the ENT department at Suez Canal University Hospitals undertook an observational case-control study. Fifty-two adult patients who present to the Suez Canal University ENT department with complaints of autophony, auditory fullness, or aerophony are diagnosed with patulous eustachian tube dysfunction through endoscopic examination of the tympanic membrane's synchronized movement with respiration. Results: The incidence rate of PET among adults was approximately 3 patients/1000 patients/year. The age of the whole studied group ranged from 20 to 60 years with mean ± SD of 37.4 ± 12.6 years. They included 23 males (44.2%) and 29 females (55.8%). The most common symptom among the studied group was aural fullness (46%), while the least common symptom was aerophony (12%); the most common risk factor among the studied patients was allergy (46.2%), while the least common was radiotherapy (3.9%); 66.7% of the patients with GERD were males, while 66.7% of the patients who lost weight were females; 58.3% of the patients with allergies were females, and also 60% of the patients with thin built were females. In the case group, there is a significant higher change of middle ear compliance in ipsilateral nostril breathing than the mouth breathing and nasal breathing. The sensitivity of the acoustic reflex decay test to diagnose PET with reference to the gold standard test is 88.5% (23/26*100), the specificity is 100% (26/26*100), and the positive predictive value is 100% (23/23*100). Conclusion: The sensitivity of the acoustic reflex decay test to diagnose PET with reference to the gold standard test is high, and the specificity is very high with very good diagnostic accuracy. [ABSTRACT FROM AUTHOR]

Objectives: Type 1 diabetes (T1D) has been associated with several comorbidities such as ocular, renal, and cardiovascular complications. However, the effect of T1D on the auditory system and sensorineural hearing loss (SNHL) is still not clear. The aim of this study was to conduct a systematic review to evaluate whether T1D is associated with hearing impairment. Methods: The databases PubMed, Science Direct, Scopus, and EMBASE were searched in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. Three reviewers independently screened, selected, and extracted data. The Joanna Briggs Institute (JBI) Critical Appraisal Tools for Analytical cross-sectional and case-control studies were used to perform quality assessment and risk of bias analysis on eligible studies. Results: After screening a total of 463 studies, 11 eligible original articles were included in the review to analyze the effects of T1D on the auditory system. The included studies comprised cross-sectional and case-control investigations. A total of 5,792 patients were evaluated across the 11 articles included. The majority of the studies showed that T1D was associated with hearing impairment compared to controls, including differences in PTAs and OAEs, increased mean hearing thresholds, altered acoustic reflex thresholds, and problems with the medial olivocochlear (MOC) reflex inhibitory effect. Significant risk factors included older age, increased disease duration, and higher HbA1C levels. Conclusions: This systematic review suggests that there is a correlation between T1D and impairment on the auditory system. A multidisciplinary collaboration between endocrinologists, otolaryngologists, and audiologists will lead to early detection of hearing impairment in people with T1D resulting in early intervention and better clinical outcomes in pursuit of improving the quality of life of affected individuals. Registration: This systematic review is registered in PROSPERO (CRD42023438576). [ABSTRACT FROM AUTHOR]

Vestibular schwannomas (VS) account for approximately 8% of all intracranial neoplasms. Importantly, the cost of the diagnostic workup for VS, including the screening modalities most commonly used, has not been thoroughly investigated. Our aim is to conduct a systematic review of the published literature on costs associated with VS screening. A systematic review of the literature for cost of VS treatment was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The terms "vestibular schwannoma," "acoustic neuroma," and "cost" were queried using the PubMed and Embase databases. Studies from all countries were considered. Cost was then corrected for inflation using the US Bureau of Labor Statistics Inflation Calculator, correcting to April 2022. The search resulted in an initial review of 483 articles, of which 12 articles were included in the final analysis. Screening criteria were used for non-neurofibromatosis type I and II patients who complained of asymmetric hearing loss, tinnitus, or vertigo. Patients included in the studies ranged from 72 to 1249. The currency and inflation-adjusted mean cost was $418.40 (range, $21.81 to $487.03, n = 5) for auditory brainstem reflex and $1433.87 (range, $511.64 to $1762.15, n = 3) for non-contrasted computed tomography. A contrasted magnetic resonance imaging (MRI) scan was found to have a median cost of $913.27 (range, $172.25–$2733.99; n = 8) whereas a non-contrasted MRI was found to have a median cost of $478.62 (range, $116.61–$3256.38, n = 4). In terms of cost reporting, of the 12 articles, 1 (8.3%) of them separated out the cost elements, and 10 (83%) of them used local prices, which include institutional costs and/or average costs of multiple institutions. Our findings describe the limited data on published costs for screening and imaging of VS. The paucity of data and significant variability of costs between studies indicates that this endpoint is relatively unexplored, and the cost of screening is poorly understood. [ABSTRACT FROM AUTHOR]

Different types of resistance to passive movement, i.e. hypertonia, were described in schizophrenia spectrum disorders (SSD) long before the introduction of antipsychotics. While these have been rediscovered in antipsychotic-naïve patients and their non-affected relatives, the existence of intrinsic hypertonia vs drug-induced parkinsonism (DIP) in treated SSD remains controversial. This integrative review seeks to develop a commonly accepted framework to specify the putative clinical phenomena, highlight conflicting issues and discuss ways to challenge each hypothesis and model through adversarial collaboration. The authors agreed on a common framework inspired from systems neuroscience. Specification of DIP, locomotor paratonia (LMP) and psychomotor paratonia (PMP) identified points of disagreement. Some viewed parkinsonian rigidity to be sufficient for diagnosing DIP, while others viewed DIP as a syndrome that should include bradykinesia. Sensitivity of DIP to anticholinergic drugs and the nature of LPM and PMP were the most debated issues. It was agreed that treated SSD should be investigated first. Clinical features of the phenomena at issue could be confirmed by torque, EMG and joint angle measures that could help in challenging the selectivity of DIP to anticholinergics. LMP was modeled as the release of the reticular formation from the control of the supplementary motor area (SMA), which could be challenged by the tonic vibration reflex or acoustic startle. PMP was modeled as the release of primary motor cortex from the control of the SMA and may be informed by subclinical echopraxia. If these challenges are not met, this would put new constraints on the models and have clinical and therapeutic implications. [ABSTRACT FROM AUTHOR]

Objectives: The first aim of this study is to determine whether subjective tinnitus has an effect on the medial olivocochlear bundle function in the auditory efferent system, with the contralateral acoustic reflex suppression test. The second aim is to contribute to the literature on the auditory efferent system. Materıals and Methods: The study included 20 individuals with chronic subjective tinnitus and 28 healthy controls. Acoustic reflex measurement was applied to both groups at 0.5, 1, and 2 kHz with and without contralateral noise. The contralateral suppression of the acoustic reflex (CSAR) results of both groups were compared in terms of CSAR threshold (CSART) and CSAR amplitude (CSARA). Results: There was no significant difference between the control and tinnitus groups in terms of CSART (P > 0.05), except that the left ear of the tinnitus group was higher than the control group at 0.5 kHz (P = 0.015). There was no significant difference in CSARA of the ears at all frequencies between the two groups (P > 0.05). Conclusion: These results suggest that the CSAR test can be used as a complementary test in the evaluation of the auditory efferent system of individuals with chronic subjective tinnitus. [ABSTRACT FROM AUTHOR]

Background: Rheumatoid arthritis (RA), a multisystem disorder of unknown etiology, is a chronic polyarthritic condition. Hearing loss (HL) among RA patients is a common finding (prevalence of 60%-62%) with conductive HL (CHL) being more common than sensorineural HL (SNHL). Objectives: The present study was conducted in this context as an attempt (i) to find the prevalence of HL among RA patients, (ii) to assess the type of HL in RA patients, and (iii) to find any correlation between duration of illness, gender, and age of patients. Materials and Methods: This was a case-control study which included 25 RA patients and 25 normal controls. All subjects underwent complete clinical examination and audiological evaluation which included pure-tone audiometry (PTA), tympanometry, and acoustic reflex. Results: Out of 25 cases, 66% had HL (CHL - 50% and SNHL - 16%) while 34% had normal hearing. On tympanometry, 9 out of 25 cases showed as type of curve while the remaining 16 had A type on the right side. On the left side, 7 out of 25 cases showed as type of curve and 18 had A type. Acoustic reflex was absent in 15, delayed in 3, and present in 7 on the right side. On the left, it was absent in 12, delayed in 4, and present in 8. All the controls had normal hearing threshold (<25 dB), A-type tympanogram, and acoustic reflex present in both ears. Conclusion: This study indicates that a large number of RA patients are destined to have ear involvement. Hence, auditory screening using PTA should be done routinely in RA patients and early diagnosis of these patients can help in better rehabilitation. [ABSTRACT FROM AUTHOR]

Tinnitus, reduced sound-level tolerance, and difficulties hearing in noisy environments are the most common complaints associated with sensorineural hearing loss in adult populations. This study aims to clarify if cochlear neural degeneration estimated in a large pool of participants with normal audiograms is associated with self-report of tinnitus using a test battery probing the different stages of the auditory processing from hair cell responses to the auditory reflexes of the brainstem. Self-report of chronic tinnitus was significantly associated with (1) reduced cochlear nerve responses, (2) weaker middle-ear muscle reflexes, (3) stronger medial olivocochlear efferent reflexes and (4) hyperactivity in the central auditory pathways. These results support the model of tinnitus generation whereby decreased neural activity from a damaged cochlea can elicit hyperactivity from decreased inhibition in the central nervous system. [ABSTRACT FROM AUTHOR]

This standard provides design information for the A-, B-, C-, D-, E-, G-, and U-weighting networks used for acoustical measurements. The analog poles and zeros for each weighting network are given, along with the equations for computing the magnitude and phase responses as functions of frequency. Coefficients and equations for computing the impulse and step responses of the A-, B-, C-, D-, and E-weighting networks as functions of time are provided in an informative annex. Information regarding digital implementation is also provided in an informative annex. Matlab scripts for the design of analog and digital implementations of the weighting networks described in this standard are also supplied. [ABSTRACT FROM AUTHOR]

Purpose: Animal models and human temporal bones indicate that noise exposure is a risk factor for cochlear synaptopathy, a possible etiology of tinnitus. Veterans are exposed to high levels of noise during military service. Therefore, synaptopathy may explain the high rates of noise-induced tinnitus among Veterans. Although synaptopathy cannot be directly evaluated in living humans, animal models indicate that several physiological measures are sensitive to synapse loss, including the auditory brainstem response (ABR), the middle ear muscle reflex (MEMR), and the envelope following response (EFR). The purpose of this study was to determine whether tinnitus is associated with reductions in physiological correlates of synaptopathy that parallel animal studies. Method: Participants with normal audiograms were grouped according to Veteran status and tinnitus report (Veterans with tinnitus, Veterans without tinnitus, and non-Veteran controls). The effects of being a Veteran with tinnitus on ABR, MEMR, and EFR measurements were independently modeled using Bayesian regression analysis. Results: Modeled point estimates of MEMR and EFR magnitude showed reductions for Veterans with tinnitus compared with non-Veterans, with the most evident reduction observed for the EFR. Two different approaches were used to provide context for the Veteran tinnitus effect on the EFR by comparing to age-related reductions in EFR magnitude and synapse numbers observed in previous studies. These analyses suggested that EFR magnitude/synapse counts were reduced in Veterans with tinnitus by roughly the same amount as over 20 years of aging. Conclusion: These findings suggest that cochlear synaptopathy may contribute to tinnitus perception in noise-exposed Veterans. [ABSTRACT FROM AUTHOR]

This study aimed to scope the literature, identify knowledge gaps, appraise results, and synthesize the evidence on the audiological evaluation of workers exposed to solvents. We searched Medline, PubMed, Embase, CINAHL, and NIOSHTIC-2 up to March 22, 2021. Using Covidence, two authors independently assessed study eligibility, risk of bias, and extracted data. National Institute of Health Quality Assessment Tools was used in the quality evaluation of included studies; the Downs and Black checklist was used to assess the risk of bias. Of 454 located references, 37 were included. Twenty-five tests were studied: two tests to measure hearing thresholds, one test to measure word recognition in quiet, six electroacoustic procedures, four electrophysiological tests, and twelve behavioral tests to assess auditory processing skills. Two studies used the Amsterdam Inventory for Auditory Disability and Handicap. The quality of individual studies was mostly considered moderate, but the overall quality of evidence was considered low. The discrepancies between studies and differences in the methodologies/outcomes prevent recommending a specific test battery to assess the auditory effects of occupational solvents. Decisions on audiological tests for patients with a history of solvent exposures require the integration of the most current research evidence with clinical expertise and stakeholder perspectives. [ABSTRACT FROM AUTHOR]

Introduction: The aim of the study was to describe auditory and vestibular findings in Brazilian adults after COVID-19 in a municipality from the outskirts of the São Paulo state. Methods: This was a transversal and exploratory study comprising sixteen participants infected by the SARS-CoV-2 virus, confirmed through RT-PCR detection, aged 20 to 55 years. Subjects underwent anamnesis, vestibular and auditory testing. Fisher's exact test was used to evaluate medication use, chemical and physical exposure, and occupational risk and McNemar test was used to compare auditory and vestibular symptoms pre- and post-COVID-19. Results: Most patients were women (75%) and had been exposed to the virus over 90 days before testing (50%). 18.8% used hydroxychloroquine, 68.8% used ivermectin, and 87.5% used azithromycin to treat COVID-19. Auditory complaints were reported by 31.2% and vestibular by 18.7%. There was no statistical difference before and after the disease. Other reported symptomatology was hair loss, pain, fatigue, memory loss, difficulty to concentrate, and headache. Auditory findings were relevant in contralateral acoustic reflex, in the distortion-product otoacoustic emissions, and in the brainstem auditory evoked potential, characterizing a neurosensorial compromise. 43.74% of patients had altered vectonystagmography. When comparing both ears, no statistical relevance was found; however, when results were crossed with medication use and exposures, there was statistical relevance in the amplitude of the V wave for medications and absolute latency of the V wave to exposure to physical agents. Discussion/Conclusion: This study demonstrated auditory and vestibular findings of neurosensorial nature, considering hearing and of a peripheral vestibulopathy. As it is a study of transversal nature, it is not possible to extend results to general population; yet it may be a finding to future studies. [ABSTRACT FROM AUTHOR]

Purpose: Type 2 diabetes mellitus (T2DM) may induce micro-vascular and macro-vascular changes that can lead to neuropathic changes which may affect the auditory pathway resulting in hearing loss. The study aims to evaluate the outcome of ipsilateral and contralateral acoustic reflex (AR) parameters and reflex decay tests (RDT) in patients with T2DM, and the relationship between average AR parameters, and duration and control of T2DM. Methods: An analytical cross-sectional study was conducted in a tertiary care setup in 126 subjects which included 42 subjects with T2DM between 30 and 60 years of age, age-matched with 84 non-diabetic subjects. The subjects were evaluated for pure tone average (PTA), speech identification score (SIS), AR parameters [acoustic reflex threshold (ART), acoustic reflex amplitude (ARA), acoustic reflex latency (ARL)] and RDT. Results: The subjects with T2DM showed increased PTA in both ears when compared to the subjects with no disease. No significant difference was found in the SIS between both groups. There was no significant difference in the ART and ARL between the two groups. There was a significant difference in the ipsilateral and contralateral ARA at 500 Hz, 1000 Hz and broadband noise (BBN) when compared between the diabetic and non-diabetic groups. No significant difference was found between average AR parameters and duration and control of T2DM. Conclusion: T2DM increases hearing thresholds and reduces ipsilateral and contralateral AR at lower frequencies and BBN. Duration and control of T2DM do not affect the AR parameters. [ABSTRACT FROM AUTHOR]

Background: Radiation-associated dysphagia is defined as impaired swallowing efficiency/safety following (chemo)radiotherapy in head and neck cancer patients. In a dysphagia framework, impaired coughing may lead to lung aspiration and fatal lung infection. Although cough efficacy is a predictor of the risk of aspiration, cough investigation is minimal in patients with radiation-associated dysphagia. Because cough is a transient signal, existing software for speech analysis are not appropriate. The goal of our project is to develop an assessment method using acoustic features related to voluntary and reflexive coughs as biomarkers of the risk of penetration/aspiration in patients with radiation-associated dysphagia. Methods: Healthy subjects and head and neck cancer patients with and without dysphagia will produce voluntary coughs, throat clearings and reflexive coughs. Recordings will be made using an acoustic microphone and a throat microphone. The recorded signals will be manually segmented and subsequently analysed with a software under development. Automatic final segmentation enables to measure cough duration. The first method of analysis includes temporal features: the amplitude contour, the sample entropy and the kurtosis. These features report respectively the strength, the unpredictability (turbulence noise due to the air jet) and the impulsive quality (burst) of the signal. The second method of analysis consists of a spectral decomposition of the relative cough signal energy into several frequency bands (0–400 Hz, 400–800 Hz, 800–1600 Hz, 1600–3200 Hz, > 3200 Hz). The primary outcome of this exploratory research project is the identification of a set of descriptive acoustic cough features in healthy subjects as reference data (ACCOUGH). The secondary outcome of this research in head and neck cancer patients with radiation-associated dysphagia includes the identification of (1) a set of descriptive acoustic cough features as biomarkers of penetration-aspiration (ACCOUGH-P/A), (2) swallowing scores, (3) voice features and (4) aerodynamic cough features. Discussion: This study is expected to develop methods of acoustic cough analysis to enhance the assessment of radiation-associated dysphagia in head and neck cancer patients following (chemo)radiation. Trial registration: International Standard Randomized Controlled Trials Number (ISRCTN) registry ISRCTN16540497. Accepted on 23 June 2023. [ABSTRACT FROM AUTHOR]

Rapid perception of the location of the fire point is crucial to building fire emergency response in the process of building fire emergency response, which can help firefighters direct fire-fighting operations, effectively control fire sources, and provide strong evidence for the analysis and investigation of fire causes. This paper uses acoustic CT temperature measurement technology to determine the fire source location of a building fire and verifies its validity and applicability as follows: we construct various fire point numerical models based on the fire dynamics simulator (FDS) and obtain temperature data at different times; neural network means were used to obtain the time-of-flight (TOF) of an acoustic wave traveling; the large ill-conditioned matrix equation of acoustic flight under different meshing schemes was constructed and solved based on the simultaneous algebraic reconstruction technique (SART) and least squares QR-decomposition (LSQR), and then reconstruction temperature data under each scheme were obtained. Through the error analysis, the reconstruction effect of each reconstruction scheme is evaluated, and then the applicability of the location coordinate determination of the fire point is analyzed. The results show that the determination of the fire location under the conditions of various fire points in the building space can be realized by acoustic CT temperature measurement technology. [ABSTRACT FROM AUTHOR]

Noise and solvents are two occupational exposures with possible hearing effects. We aimed to assess the effect of exposure to noise and organic solvents on acoustic reflex. This cross-sectional study was conducted on three groups: 80 workers exposed to impermissible amounts of organic solvents (mainly styrene), 78 workers exposed to loud noise and 67 subjects as a control group. The hearing status of the subjects was assessed by pure tone audiometry and acoustic reflex. Data were analysed by SPSS (ver. 20) (SPSS Inc., Chicago, IL) using Student's t-test, chi-square test and ANOVA. The mean hearing threshold at high frequencies was significantly higher in the noise group, followed by the solvent group, compared to the control group (p<.0001). Mean acoustic reflex was higher in the solvent group, followed by the noise group (p<.05). The frequency of absent acoustic reflex was also significantly higher in noise and solvent groups than in controls (p<.05). This study suggests that exposure to organic solvents alone without simultaneous noise, despite a normal hearing threshold, can affect acoustic reflex, so conducting preventive hearing tests such as acoustic reflex test, in workers exposed to organic solvents, may be one of the effective ways to prevent occupational hearing loss in these workers. [ABSTRACT FROM AUTHOR]

Misophonia is characterised by abnormal reactions to certain sounds such as sounds of eating, breathing, nose sniffing. Misophonia can be seen in individuals with normal hearing or hearing loss. The aim of this study to evaluate central auditory processing in misophonia patients with temporal processing tests, such as the Frequency Pattern Test (FPT), Duration Pattern Test (DPT), and Gaps-in-Noise Test (GIN). Thirty patients with misophonia and 30 healthy control subjects were included in this study. The pure tone audiometry test, tympanometry test, and acoustic reflex test were administered to all participants. The DPT, FPT, and GIN tests were conducted with all participants. There was no significant difference in the DPT scores between the two groups for both ears (p >.05). There was no significant difference in the FPT scores between the two groups for both ears (p >.05), and there was no significant difference in the GIN scores and GIN threshold (p >.05). There was no difference between the healthy individuals and the misophonia patients when the temporal process of central auditory processing was evaluated. [ABSTRACT FROM AUTHOR]

Reinvention of the form of expression is a conceptual approach characteristic for the evolution of all arts. This research study provides one such step forward in the advancement of scientific paper, a standard form of expression in natural sciences, toward more progressive terrains. The paper adopts the form of a theatrical play where a scientific family of four attempts to find the way around a writer’s block (Act I). Their idealess sense of confinement is overcome through arts or, more specifically, through scientific research implementing the aesthetics of music as its key element. The characters record compositions differing in the degrees of consonance, rhythmicity and tonality, and play them to birds to observe their vocal and behavioral responses (Act II). They note that the birdsong volume drops significantly when the piano tunes, especially the compositionally complex ones, are played to the birds and increases significantly when the white noise of ocean waves is played. The bird count experiment proves indirectly that the birdsong volume reduction is an auditory response of the birds to music rather than the effect of their migrating to or away from the sound source. This science with the flavor of art elevates the characters beyond the limits of their confinement and they, exalted and uplifted, gain ideas for creative research in their own disciplines of biomedical science (Act III). They relinquish the newly gained freedom in favor of embracing love for humanity that underlies medical research and return to their confinement, where they conduct, in the coda of the paper, a series of experiments that venture beyond musicology and ornithology and fall in the domains of tissue engineering and drug delivery, but also psychology (Act III). First, sparrow nests are used as templates for tissue engineering constructs, which facilitate the growth of human fibroblastic cells better than their artificial, gridded replicas. Next, the shell of an Easter egg, predominantly calcite in composition, is used with success as a drug delivery carrier. Lastly, the bird nest drawing experiment demonstrates a greater mental health of children than that of the adults, correlating with one of the overarching points of the paper, which is to present children as a model for grownups to follow rather than the other way around. Over the course of the play, the characters discuss the value of the various fusions between art and science, question the limits of human language and repeatedly go off-topic to celebrate the freeness of the creative thinking process. The play reports on real-life research methods and scientific results through a narrative, without diminishing their empirical rigor and analytical accuracy. [ABSTRACT FROM AUTHOR]