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Brain Sciences Jun 2024Despite substantial progress in investigating its psychophysical complexity, tinnitus remains a scientific and clinical enigma. The present study, through an ecological...
BACKGROUND
Despite substantial progress in investigating its psychophysical complexity, tinnitus remains a scientific and clinical enigma. The present study, through an ecological and multidisciplinary approach, aims to identify associations between electroencephalographic (EEG) and psycho-audiological variables.
METHODS
EEG beta activity, often related to stress and anxiety, was acquired from 12 tinnitus patients (TIN group) and 7 controls (CONT group) during an audio cognitive task and at rest. We also investigated psychological (SCL-90-R; STAI-Y; BFI-10) and audiological (THI; TQ12-I; Hyperacusis) variables using non-parametric statistics to assess differences and relationships between and within groups.
RESULTS
In the TIN group, frontal beta activity positively correlated with hyperacusis, parietal activity, and trait anxiety; the latter is also associated with depression in CONT. Significant differences in paranoid ideation and openness were found between groups.
CONCLUSIONS
The connection between anxiety trait, beta activity in the fronto-parietal cortices and hyperacusis provides insights into brain functioning in tinnitus patients, offering quantitative descriptions for clinicians and new multidisciplinary treatment hypotheses.
PubMed: 38928570
DOI: 10.3390/brainsci14060570 -
Brain Sciences May 2024Tinnitus is a common phantom auditory percept believed to be related to plastic changes in the brain due to hearing loss. However, tinnitus can also occur in the absence...
Tinnitus is a common phantom auditory percept believed to be related to plastic changes in the brain due to hearing loss. However, tinnitus can also occur in the absence of any clinical hearing loss. In this case, since there is no hearing loss, the mechanisms that drive plastic changes remain largely enigmatic. Previous studies showed subtle differences in sound-evoked brain activity associated with tinnitus in subjects with tinnitus and otherwise normal hearing, but the results are not consistent across studies. Here, we aimed to investigate these differences using monaural rather than binaural stimuli. Sound-evoked responses were measured using functional magnetic resonance imaging (MRI) in participants with and without tinnitus. All participants had clinically normal audiograms. The stimuli were pure tones with frequencies between 353 and 8000 Hz, presented monaurally. A Principal Component Analysis (PCA) of the response in the auditory cortex revealed no difference in tonotopic organization, which confirmed earlier studies. A GLM analysis showed hyperactivity in the lateral areas of the bilateral auditory cortex. Consistent with the tonotopic map, this hyperactivity mainly occurred in response to low stimulus frequencies. This may be related to hyperacusis. Furthermore, there was an interaction between stimulation side and tinnitus in the parahippocampus. This may reflect an interference between tinnitus and spatial orientation.
PubMed: 38928544
DOI: 10.3390/brainsci14060544 -
European Journal of Pain (London,... Jun 2024Migraine is a genetically determined disorder that predisposes to recurrent episodes of headache. Interleukin (IL)-18 is a pro-inflammatory cytokine that seems to play a...
BACKGROUND
Migraine is a genetically determined disorder that predisposes to recurrent episodes of headache. Interleukin (IL)-18 is a pro-inflammatory cytokine that seems to play a role in migraine pathophysiology, and its genetic variants could potentially impact susceptibility to migraine.
OBJECTIVE
To investigate the association between IL18 rs360717 and rs187238 genetic variants with migraine diagnosis and its clinical characteristics.
METHODS
A case-control study was conducted with 152 people with migraine and 155 healthy controls, matched by sex, age, ethnicity, and body mass index. Clinical characteristics of migraine, as well as validated questionnaires regarding disability and impact of migraine, presence of allodynia, anxiety, depression, and hyperacusis were collected. Genotyping for IL18 rs360717 and rs187238 variants was performed using real-time polymerase chain reaction (qPCR) and TaqMan™ method.
RESULTS
The IL18 rs360717A and rs187238G alleles were associated with increased chance of being diagnosed with migraine (OR = 1.53, 95%CI 1.05-2.24, p = 0.028 and OR = 1.46, 95%CI 1.00-2.14, p = 0.049, respectively). In the dominant model, the rs360717GA + AA genotypes were also associated with a higher chance of migraine than the GG genotype (OR = 1.69, 95%CI 1.05-2.73, p = 0.030). In women, in addition to the previous associations, there was also an effect of the variants on the chance of migraine in the codominant models and dominant models. Furthermore, among women, there was an influence on the prevalence of postdrome perception with rs360717GA + AA (OR = 3.04, 95%CI 1.10-8.42, p = 0.032) and rs187238CG + GG (OR = 2.97, 95%CI 1.08-8.21, p = 0.035).
CONCLUSION
IL18 rs360717 and rs187238 variants were associated with migraine diagnosis and postdrome symptoms, especially in women.
SIGNIFICANCE
This study has demonstrated that IL18 rs360717 and rs187238 variants play a role in migraine, influencing the chance of being diagnosed with migraine, particularly among women. There are prospects that IL18 variants could be considered potential genetic biomarkers for migraine.
PubMed: 38922725
DOI: 10.1002/ejp.2302 -
BioRxiv : the Preprint Server For... Jun 2024Fragile X syndrome (FXS) is an X-linked disorder that often leads to intellectual disability, anxiety, and sensory hypersensitivity. While sound sensitivity...
Fragile X syndrome (FXS) is an X-linked disorder that often leads to intellectual disability, anxiety, and sensory hypersensitivity. While sound sensitivity (hyperacusis) is a distressing symptom in FXS, its neural basis is not well understood. It is postulated that hyperacusis may stem from temporal lobe hyperexcitability or dysregulation in topdown modulation. Studying the neural mechanisms underlying sound sensitivity in FXS using scalp electroencephalography (EEG) is challenging because the temporal and frontal regions have overlapping neural projections that are difficult to differentiate. To overcome this challenge, we conducted EEG source analysis on a group of 36 individuals with FXS and 39 matched healthy controls. Our goal was to characterize the spatial and temporal properties of the response to an auditory chirp stimulus. Our results showed that males with FXS exhibit excessive activation in the frontal cortex in response to the stimulus onset, which may reflect changes in top-down modulation of auditory processing. Additionally, during the chirp stimulus, individuals with FXS demonstrated a reduction in typical gamma phase synchrony, along with an increase in asynchronous gamma power, across multiple regions, most strongly in temporal cortex. Consistent with these findings, we observed a decrease in the signal-to-noise ratio, estimated by the ratio of synchronous to asynchronous gamma activity, in individuals with FXS. Furthermore, this ratio was highly correlated with performance in an auditory attention task. Compared to controls, males with FXS demonstrated elevated bidirectional frontotemporal information flow at chirp onset. The evidence indicates that both temporal lobe hyperexcitability and disruptions in top-down regulation play a role in auditory sensitivity disturbances in FXS. These findings have the potential to guide the development of therapeutic targets and back-translation strategies.
PubMed: 38915683
DOI: 10.1101/2024.06.13.598957 -
Scientific Reports Jun 2024This study aims to investigate auditory hypersensitivity and cortical function in migraine patients using the Hyperacusis Questionnaire and the Event-Related Potential...
This study aims to investigate auditory hypersensitivity and cortical function in migraine patients using the Hyperacusis Questionnaire and the Event-Related Potential (ERP) technique. The study analyzes alterations in the latency and amplitude of the event-related potentials MMN and P300 components. The findings contribute to a better understanding of the physiological relationship between migraine and auditory hypersensitivity. Seventeen migraine patients were admitted to the outpatient clinic of the Department of Otorhinolaryngology-Head and Neck Surgery at Peking University People's Hospital from June 2023 to September 2023. Nineteen matched healthy subjects were also selected. All participants underwent the pure tone audiometry and the auditory brainstem response test to determine hearing thresholds, the Hyperacusis Questionnaire, the Tinnitus Handicap Inventory, and an ERP examination. The Oddball classical paradigm was used as the stimulation task, and electroencephalography signals were recorded synchronously. The scores of the Hyperacusis Questionnaire, latency and amplitude of MMN and P300 component were compared between the migraine group and the control group, and their correlation was analyzed. The latency of MMN at the Fz and Cz sites in migraine patients was significantly shorter than that in the control group (P < 0.05), and the amplitudes were significantly higher than those in the control group (P < 0.05). The variances in latency and amplitude of P300 at Cz and Pz sites in migraine patients were not statistically significant when compared with the control group. (P > 0.05). The Hyperacusis Questionnaire was negatively correlated with MMN latency, with a correlation coefficient of - 0.374 (P = 0.025), and positively correlated with MMN amplitude, with a correlation coefficient of 0.378 (P = 0.023). There was no significant similarity between the Hyperacusis Questionnaire and P300 latency and amplitude (P > 0.05). Overall, auditory hypersensitivity was enhanced in individuals with migraines compared to healthy individuals, leading to faster information processing, while there may be less impairment in cognitive function.
Topics: Humans; Female; Migraine Disorders; Male; Hyperacusis; Adult; Surveys and Questionnaires; Middle Aged; Electroencephalography; Event-Related Potentials, P300; Evoked Potentials; Case-Control Studies; Young Adult; Audiometry, Pure-Tone
PubMed: 38898084
DOI: 10.1038/s41598-024-65014-3 -
Journal of Clinical Medicine Jun 2024The purpose of this study was to investigate the hearing characteristics and causes of sudden sensorineural hearing loss (SSNHL) in patients aged from 15 to 40 years,...
The purpose of this study was to investigate the hearing characteristics and causes of sudden sensorineural hearing loss (SSNHL) in patients aged from 15 to 40 years, focusing on audiological outcomes one year after the diagnosis. The medical records of individuals with SSNHL who were referred to our tertiary-level audiologic center were reviewed. All patients had undergone comprehensive diagnostic evaluations, including high-resolution 3D-FLAIR delayed magnetic resonance imaging (MRI), cone beam computed tomography (CBCT), and screening for coagulation, infectious, and autoimmune diseases. Overall, 56 patients (mean age 28.1 ± 7.6 years) were included in the study. The hearing threshold in the affected ear improved significantly from 56.0 ± 18.0 dB at the diagnosis to 46.9 ± 22.3 dB after one year ( = 0.02). The degree of hearing loss, audiometric configurations, hearing improvements, and adherence to hearing treatments showed considerable variability among patients. Aural fullness, tinnitus, and hyperacusis were the predominant symptoms associated with SSNHL, and their prevalence decreased significantly over time. The diagnostic protocol led to the identification of the specific cause of SSNHL in 75% (42/56) of patients. The known etiology was found to be otological (39.3%), infectious (21.4%), autoimmune (7.1%), vascular (5.4%), or neoplastic (1.8%). In particular, Menière's disease (n = 12), isolated cochlear endolymphatic hydrops (n = 6), HSV-1 (n = 5), and EBV (n = 4) infections were the most frequent causes of SSNHL. The identification of the specific etiology of SSNHL may facilitate a more personalized approach to management and treatment.
PubMed: 38893014
DOI: 10.3390/jcm13113303 -
Cephalalgia : An International Journal... Jun 2024This study aimed to identify the potential subgroups of migraines based on the patterns of migraine associated symptoms, vestibular and auditory symptoms using latent...
OBJECTIVE
This study aimed to identify the potential subgroups of migraines based on the patterns of migraine associated symptoms, vestibular and auditory symptoms using latent class analysis and to explore their characteristics.
METHOD
A total of 555 patients with migraine participated in the study. Symptoms such as nausea, vomiting, photophobia, phonophobia, osmophobia, visual symptoms, vestibular symptoms (dizziness, vertigo), and auditory symptoms (tinnitus, hearing loss, aural fullness) were assessed. Latent class analysis was performed to identify subgroups of migraines. Covariates such as gender, age of migraine onset, frequency of migraine attacks per month, and family history were also considered.
RESULTS
The analysis revealed four latent classes: the Prominent Vestibular; Prominent Nausea; Presenting Symptoms but not prominent or dominant; and Sensory Hypersensitivity groups. Various covariates, such as gender, age of migraine onset, and frequency of migraine attacks, demonstrated significant differences among the four groups. The Sensory Hypersensitivity group showed the presence of multiple sensory symptoms, earlier age of migraine onset, and higher proportion of females. The Prominent Vestibular group had the highest probability of dizziness or vertigo but lacked the presence of auditory symptoms. The Prominent Nausea group exhibited prominent nausea. The Presenting Symptoms but not prominent or dominant group comprised individuals with the highest migraine attacks per month and proportion of chronic migraine.
CONCLUSION
This study identifies four subgroups of migraines based on the patterns of symptoms. The findings suggest potential different but overlapped mechanisms behind the vestibular and auditory symptoms of migraine. Considering the different patterns of migraine-related symptoms may provide deeper insights for patients' prognosis and clinical decision-making.
Topics: Humans; Migraine Disorders; Female; Male; Adult; Middle Aged; Latent Class Analysis; Vertigo; Young Adult; Nausea; Dizziness; Aged; Adolescent; Vestibular Diseases
PubMed: 38887813
DOI: 10.1177/03331024241262488 -
Frontiers in Neuroscience 2024Both tinnitus and hyperacusis, likely triggered by hearing loss, can be attributed to maladaptive plasticity in auditory perception. However, owing to their...
INTRODUCTION
Both tinnitus and hyperacusis, likely triggered by hearing loss, can be attributed to maladaptive plasticity in auditory perception. However, owing to their co-occurrence, disentangling their neural mechanisms proves difficult. We hypothesized that the neural correlates of tinnitus are associated with neural activities triggered by low-intensity tones, while hyperacusis is linked to responses to moderate- and high-intensity tones.
METHODS
To test these hypotheses, we conducted behavioral and electrophysiological experiments in rats 2 to 8 days after traumatic tone exposure.
RESULTS
In the behavioral experiments, prepulse and gap inhibition tended to exhibit different frequency characteristics (although not reaching sufficient statistical levels), suggesting that exposure to traumatic tones led to acute symptoms of hyperacusis and tinnitus at different frequency ranges. When examining the auditory cortex at the thalamocortical recipient layer, we observed that tinnitus symptoms correlated with a disorganized tonotopic map, typically characterized by responses to low-intensity tones. Neural correlates of hyperacusis were found in the cortical recruitment function at the multi-unit activity (MUA) level, but not at the local field potential (LFP) level, in response to moderate- and high-intensity tones. This shift from LFP to MUA was associated with a loss of monotonicity, suggesting a crucial role for inhibitory synapses.
DISCUSSION
Thus, in acute symptoms of traumatic tone exposure, our experiments successfully disentangled the neural correlates of tinnitus and hyperacusis at the thalamocortical recipient layer of the auditory cortex. They also suggested that tinnitus is linked to central noise, whereas hyperacusis is associated with aberrant gain control. Further interactions between animal experiments and clinical studies will offer insights into neural mechanisms, diagnosis and treatments of tinnitus and hyperacusis, specifically in terms of long-term plasticity of chronic symptoms.
PubMed: 38881748
DOI: 10.3389/fnins.2024.1385942 -
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 Jun 2024Since the presence of tinnitus is not always associated with audiometric hearing loss, it has been hypothesized that hidden hearing loss may act as a potential trigger...
Since the presence of tinnitus is not always associated with audiometric hearing loss, it has been hypothesized that hidden hearing loss may act as a potential trigger for increased central gain along the neural pathway leading to tinnitus perception. In recent years, the study of hidden hearing loss has improved with the discovery of cochlear synaptopathy and several objective diagnostic markers. This study investigated three potential markers of peripheral hidden hearing loss in subjects with tinnitus: extended high-frequency audiometric thresholds, the auditory brainstem response, and the envelope following response. In addition, speech intelligibility was measured as a functional outcome measurement of hidden hearing loss. To account for age-related hidden hearing loss, participants were grouped according to age, presence of tinnitus, and audiometric thresholds. Group comparisons were conducted to differentiate between age- and tinnitus-related effects of hidden hearing loss. All three markers revealed age-related differences, whereas no differences were observed between the tinnitus and non-tinnitus groups. However, the older tinnitus group showed improved performance on low-pass filtered speech in noise tests compared to the older non-tinnitus group. These low-pass speech in noise scores were significantly correlated with tinnitus distress, as indicated using questionnaires, and could be related to the presence of hyperacusis. Based on our observations, cochlear synaptopathy does not appear to be the underlying cause of tinnitus. The improvement in low-pass speech-in-noise could be explained by enhanced temporal fine structure encoding or hyperacusis. Therefore, we recommend that future tinnitus research takes into account age-related factors, explores low-frequency encoding, and thoroughly assesses hyperacusis.
PubMed: 38852534
DOI: 10.1016/j.heares.2024.109050