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BioRxiv : the Preprint Server For... May 2024Parvalbumin-expressing inhibitory neurons (PVNs) stabilize cortical network activity, generate gamma rhythms, and regulate experience-dependent plasticity. Here, we...
Parvalbumin-expressing inhibitory neurons (PVNs) stabilize cortical network activity, generate gamma rhythms, and regulate experience-dependent plasticity. Here, we observed that activation or inactivation of PVNs functioned like a volume knob in the mouse auditory cortex (ACtx), turning neural and behavioral classification of sound level up or down over a 20dB range. PVN loudness adjustments were "sticky", such that a single bout of 40Hz PVN stimulation sustainably suppressed ACtx sound responsiveness, potentiated feedforward inhibition, and behaviorally desensitized mice to loudness. Sensory sensitivity is a cardinal feature of autism, aging, and peripheral neuropathy, prompting us to ask whether PVN stimulation can persistently desensitize mice with ACtx hyperactivity, PVN hypofunction, and loudness hypersensitivity triggered by cochlear sensorineural damage. We found that a single 16-minute bout of 40Hz PVN stimulation session restored normal loudness perception for one week, showing that perceptual deficits triggered by irreversible peripheral injuries can be reversed through targeted cortical circuit interventions.
PubMed: 38853938
DOI: 10.1101/2024.05.30.596691 -
Hearing Research May 2024The round window (RW) membrane plays an important role in normal inner ear mechanics. Occlusion or reinforcement of the RW has been described in the context of...
The round window (RW) membrane plays an important role in normal inner ear mechanics. Occlusion or reinforcement of the RW has been described in the context of congenital anomalies or after cochlear implantation and is applied as a surgical treatment for hyperacusis. Multiple lumped and finite element models predict a low-frequency hearing loss with air conduction of up to 20 dB after RW reinforcement and limited to no effect on hearing with bone conduction stimulation. Experimental verification of these results, however, remains limited. Here, we present an experimental study measuring the impact of RW reinforcement on the middle and inner ear mechanics with air and bone conduction stimulation. In a within-specimen repeated measures design with human cadaveric specimens (n = 6), we compared the intracochlear pressures in scala vestibuli (P) and scala tympani (P) before and after RW reinforcement with soft tissue, cartilage, and bone cement. The differential pressure (P) across the basilar membrane - known to be closely related to the hearing sensation - was calculated as the complex difference between P and P. With air conduction stimulation, both P and Pincreased on average up to 22 dB at frequencies below 1500 Hz with larger effect sizes for P compared to P. The P, in contrast, decreased up to 11 dB at frequencies between 700 and 800 Hz after reinforcement with bone cement. With bone conduction, the average within-specimen effects were less than 5 dB for either P, P or P. The inter-specimen variability with bone conduction, however, was considerably larger than with air conduction. This experimental study shows that RW reinforcement impacts air conduction stimulation at low frequencies. Bone conduction stimulation seems to be largely unaffected. From a clinical point of view, these results support the hypothesis that delayed loss of air conduction hearing after cochlear implantation could be partially explained by the impact of RW reinforcement.
PubMed: 38850830
DOI: 10.1016/j.heares.2024.109049 -
BMC Neurology May 2024Surveys using questionnaires to collect epidemiologic data may be subject to misclassification. Here, we analyzed a headache questionnaire to evaluate which questions...
A study to investigate the prevalence of headache disorders and migraine conducted using medical claims data and linked results from online surveys: post-hoc analysis of other headache disorders.
BACKGROUND
Surveys using questionnaires to collect epidemiologic data may be subject to misclassification. Here, we analyzed a headache questionnaire to evaluate which questions led to a classification other than migraine.
METHODS
Anonymized surveys coupled with medical claims data from individuals 19-74 years old were obtained from DeSC Healthcare Inc. to examine proportions of patients with primary headache disorders (i.e.; migraine, tension-type headache, cluster headache, and "other headache disorders"). Six criteria that determined migraine were used to explore how people with other headache disorders responded to these questions.
RESULTS
Among the 21480 respondents, 7331 (34.0%) reported having headaches. 691 (3.2%) respondents reported migraine, 1441 (6.7%) had tension-type headache, 21 (0.1%) had cluster headache, and 5208 (24.2%) reported other headache disorders. Responses of participants with other headache disorders were analyzed, and the top 3 criteria combined with "Symptoms associated with headache" were "Site of pain" (7.3%), "Headache changes in severity during daily activities" (6.4%), and the 3 criteria combined (8.8%). The symptoms associated with headache were "Stiff shoulders" (13.6%), "Stiff neck" (9.4%), or "Nausea or vomiting" (8.7%), Photophobia" (3.3%) and "Phonophobia" (2.5%).
CONCLUSIONS
Prevalence of migraine as diagnosed by questionnaire was much lower than expected while the prevalence of "other headache" was higher than expected. We believe the reason for this observation was due to misclassification, and resulted from the failure of the questionnaire to identify some features of migraine that would have been revealed by clinical history taking. Questionnaires should, therefore, be carefully designed, and doctors should be educated, on how to ask questions and record information when conducting semi-structured interviews with patients, to obtain more precise information about their symptoms, including photophobia and phonophobia.
Topics: Humans; Middle Aged; Adult; Male; Female; Prevalence; Migraine Disorders; Aged; Surveys and Questionnaires; Young Adult; Headache Disorders; Internet; Health Surveys
PubMed: 38796414
DOI: 10.1186/s12883-024-03675-3 -
Acta Neurochirurgica May 2024Superior Semicircular Canal Dehiscence (SSCD) is a dehiscence of the otic capsule which normally lies over the superior semicircular canal. This database constitutes the...
BACKGROUND
Superior Semicircular Canal Dehiscence (SSCD) is a dehiscence of the otic capsule which normally lies over the superior semicircular canal. This database constitutes the largest series of SSCD patients to date.
OBJECTIVE
To determine what preoperative factors, if any, contribute to postoperative outcomes and evaluate symptom resolution in a large SSCD patient cohort.
METHODS
A single-institution, retrospective chart review collected patient demographics, intraoperative findings, and pre-and postoperative symptoms. Fisher's exact t-test was performed for unpaired categorical variables, with a significance level of p < 0.05.
RESULTS
350 SSCD repairs were performed. The median age was 52 years (range: 17-86 years, ± 6.4 years), and the median follow-up duration was 4.6 months (range: 0.03-59.5 months, ± 6.8 months). Preoperative hearing loss was significantly associated with female sex (p = 0.0028). The most reported preoperative symptoms were tinnitus (77.4%), dizziness (74.0%), autophony (66.3%), amplification (63.7%), and disequilibrium (62.6%). Between patients who received unilateral versus bilateral SSCD repair, the greatest postoperative symptomatic resolution was seen in autophony (74.9%, p < 0.001), amplification (77.3%, p = 0.00027), hyperacusis (77.4%, p = 0.023), hearing (62.9%, p = 0.0063), and dizziness (54.6%, p < 0.001) for patients with unilateral SSCD repair.
CONCLUSION
Surgical repair via the middle cranial fossa approach can significantly resolve auditory, vestibular, and neurological symptoms of patients with SSCD. Although this is one of the largest single-institution SSCD studies to date, future multi-institutional, prospective studies would be beneficial to validate these results.
Topics: Humans; Middle Aged; Female; Male; Adult; Aged; Aged, 80 and over; Adolescent; Young Adult; Retrospective Studies; Semicircular Canal Dehiscence; Treatment Outcome; Semicircular Canals; Postoperative Complications; Tinnitus
PubMed: 38789840
DOI: 10.1007/s00701-024-06115-w -
Iranian Journal of Otorhinolaryngology May 2024The aim was to assess prevalence of tinnitus, hyperacusis, hearing and balance problems among patients recovered from COVID-19 infection. Self-reported ear and hearing...
INTRODUCTION
The aim was to assess prevalence of tinnitus, hyperacusis, hearing and balance problems among patients recovered from COVID-19 infection. Self-reported ear and hearing symptoms were compared in three groups comprising: confirmed COVID-19, possible COVID-19, and non-COVID-19.
MATERIALS AND METHODS
1649 participants completed the survey in this cross-sectional study. The mean age was 34 years and 65% were female. Participants with confirmed and possible COVID-19 were asked if after their infection (compared to the past) they experienced hearing loss, ringing or whistling noises, fullness or blockage in their ears, loudness of the sounds that are normal to other people bother them more (an indication of hyperacusis), dizziness, giddiness, or imbalance.
RESULTS
Among participants with confirmed COVID-19, 16% reported that compared to the past their hearing has decreased, 21.5% noticed tinnitus, 22.5% aural fullness, 26.1% hyperacusis and 17.3% balance problems. Regression models showed that compared to the non-COVID-19 group, participants with confirmed COVID-19 had odds ratios (ORs) of significantly greater than 1 in predicting presence of self-reported symptoms of hearing loss, tinnitus, aural fullness, hyperacusis and balance problems, OR=1.96 (=0.001), OR=1.63 (=0.003), OR=1.8 (<0.001), OR=2.2 (<0.001), and OR=2.99 (<0.001), respectively.
CONCLUSIONS
There seem to be higher prevalence of self-report symptoms of ear-related problems among individuals with confirmed COVID-19 infection compared to a non-COVID-19 group during the pandemic.
PubMed: 38745685
DOI: 10.22038/IJORL.2024.71040.3414 -
Iranian Journal of Otorhinolaryngology May 2024COVID-19 infection was accompanied by otologic symptoms, a pattern that was captured early by Google Trends. The objective of this study is to investigate searches for...
INTRODUCTION
COVID-19 infection was accompanied by otologic symptoms, a pattern that was captured early by Google Trends. The objective of this study is to investigate searches for otologic symptoms and identify correlations with the pandemic onset.
MATERIALS AND METHODS
Search interest for otologic symptoms was gathered using Google Trends from two years before and two years following the pandemic start date. A two-tailed Mann-Whitney U test was used to identify significant changes and effect size.
RESULTS
In total, search interest for 14 terms was collected, with significant changes identified in 11. Six terms showed increased search interest, with the most significant rises observed for headache (r=0.589, 0.001), dizziness (r=0.554, 0.001), and tinnitus (r=0.410, 0.001). Search interest decreased for five terms, with the most notable declines found in searches for migraine headache (r=0.35, 0.001) and phonophobia (r=0.22, 0.002). No significant changes were seen in ear pressure (0.142), neck pain (0.935), and sudden hearing loss (0.863) searches.
CONCLUSION
COVID-19 infection is often accompanied otologic symptoms and holds a diagnostic role. Fluctuating search interest may be attributed to a true increase in cases, media trends, or people's desires to stay informed. Google Trends robustly captured trends in search interest and presented itself as a valuable epidemiological tool.
PubMed: 38745683
DOI: 10.22038/IJORL.2024.75617.3532 -
Trends in Hearing 2024Cochlear synaptopathy, a form of cochlear deafferentation, has been demonstrated in a number of animal species, including non-human primates. Both age and noise exposure... (Review)
Review
Cochlear synaptopathy, a form of cochlear deafferentation, has been demonstrated in a number of animal species, including non-human primates. Both age and noise exposure contribute to synaptopathy in animal models, indicating that it may be a common type of auditory dysfunction in humans. Temporal bone and auditory physiological data suggest that age and occupational/military noise exposure also lead to synaptopathy in humans. The predicted perceptual consequences of synaptopathy include tinnitus, hyperacusis, and difficulty with speech-in-noise perception. However, confirming the perceptual impacts of this form of cochlear deafferentation presents a particular challenge because synaptopathy can only be confirmed through post-mortem temporal bone analysis and auditory perception is difficult to evaluate in animals. Animal data suggest that deafferentation leads to increased central gain, signs of tinnitus and abnormal loudness perception, and deficits in temporal processing and signal-in-noise detection. If equivalent changes occur in humans following deafferentation, this would be expected to increase the likelihood of developing tinnitus, hyperacusis, and difficulty with speech-in-noise perception. Physiological data from humans is consistent with the hypothesis that deafferentation is associated with increased central gain and a greater likelihood of tinnitus perception, while human data on the relationship between deafferentation and hyperacusis is extremely limited. Many human studies have investigated the relationship between physiological correlates of deafferentation and difficulty with speech-in-noise perception, with mixed findings. A non-linear relationship between deafferentation and speech perception may have contributed to the mixed results. When differences in sample characteristics and study measurements are considered, the findings may be more consistent.
Topics: Humans; Cochlea; Tinnitus; Animals; Speech Perception; Hyperacusis; Noise; Auditory Perception; Synapses; Hearing Loss, Noise-Induced; Loudness Perception
PubMed: 38738337
DOI: 10.1177/23312165241239541 -
IScience May 2024Salicylate is commonly used to induce tinnitus in animals, but its underlying mechanism of action is still debated. We therefore tested its effects on the firing...
Salicylate is commonly used to induce tinnitus in animals, but its underlying mechanism of action is still debated. We therefore tested its effects on the firing properties of neurons in the mouse inferior colliculus (IC). Salicylate induced a large decrease in the spontaneous activity and an increase of ∼20 dB SPL in the minimum threshold of single units. In response to sinusoidally modulated noise (SAM noise) single units showed both an increase in phase locking and improved rate coding. Mice also became better at detecting amplitude modulations, and a simple threshold model based on the IC population response could reproduce this improvement. The responses to dynamic random chords (DRCs) suggested that the improved AM encoding was due to a linearization of the cochlear output, resulting in larger contrasts during SAM noise. These effects of salicylate are not consistent with the presence of tinnitus, but should be taken into account when studying hyperacusis.
PubMed: 38736549
DOI: 10.1016/j.isci.2024.109691 -
Journal of Clinical Medicine May 2024Migraine is a prevalent episodic brain disorder known for recurrent attacks of unilateral headaches, accompanied by complaints of photophobia, phonophobia, nausea, and... (Review)
Review
Migraine is a prevalent episodic brain disorder known for recurrent attacks of unilateral headaches, accompanied by complaints of photophobia, phonophobia, nausea, and vomiting. Two main categories of migraine are migraine with aura (MA) and migraine without aura (MO). Early twin and population studies have shown a genetic basis for these disorders, and efforts have been invested since to discern the genes involved. Many techniques, including candidate-gene association studies, loci linkage studies, genome-wide association, and transcription studies, have been used for this goal. As a result, several genes were pinned with concurrent and conflicting data among studies. It is important to understand the evolution of techniques and their findings. This review provides a chronological understanding of the different techniques used from the dawn of migraine genetic investigations and the genes linked with the migraine subtypes.
PubMed: 38731230
DOI: 10.3390/jcm13092701 -
Heliyon May 2024Medication overuse headache (MOH) is a secondary headache disorder that leads to pronounced disability and decreased quality of life. Available therapeutic options for...
BACKGROUND
Medication overuse headache (MOH) is a secondary headache disorder that leads to pronounced disability and decreased quality of life. Available therapeutic options for MOH are limited, and many are only effective in a subset of individuals. Although the existing evidence is limited, acupuncture may be an effective treatment option for MOH.
CASE PRESENTATION
A 45-year-old Chinese woman presented to the Medical Acupuncture Department of Sanming Integrated Traditional Chinese and Western Medicine Hospital on April 11, 2022. Thirty-five years ago, she had episodic migraines. The frequency increased over time, however, and for the past 10 years she has had daily headaches. These headaches were characterized by daily persistent throbbing pain on the left side of the patient's head, accompanied by photophobia, phonophobia, neck stiffness, dizziness, and fatigue. Without painkillers, the patient rated her headache intensity as 9 out of 10 on a visual analog scale (0 = no pain, 10 = intolerable pain), and reported that the headaches lasted for up to 7 days or more. With painkillers, the headaches had a reduced intensity (5 of 10), but persisted. The patient had taken 1-3.5 compound aminopyrine phenacetin tablets daily for more than 5 years. Standard conservative therapy (patient education, medication withdrawal, and behavioral intervention) for MOH had failed to improve her symptoms. Before her visit, the patient had headache and engaged in short-term medication use on 30 days per month. The total monthly headache intensity score was 90. The patient's Migraine-Specific Quality of Life Questionnaire (MSQ) score was 33 points, her Hamilton Depression Scale (HAMD) score was 24 points, and her Hamilton Anxiety Scale (HAMA) score was 20 points.
RESULTS
After 48 acupuncture sessions over 24 weeks, the patient completely discontinued short-term analgesic use and the monthly number of headache days and headache intensity score were both reduced by 96.67 % (from 30 to 1 and 90 to 3, respectively), with no adverse effect. Compared with baseline, the MSQ, HAMD, and HAMA scores improved by 45, 17, and 16 points, respectively. At 12 months, the patient's condition remained stable and her MOH had not relapsed.
CONCLUSION
In the context of the current literature and the present case, electroacupuncture shows promise for the long-term relief of chronic migraine with MOH when other treatments fail.
PubMed: 38720738
DOI: 10.1016/j.heliyon.2024.e30417