Trait overdispersion and the role of sociality in the assembly of social spider communities across the Americas.

Among the factors that may lead to differences in resource use among closely related species, body size and morphology have been traditionally considered to play a role in community assembly. Here we argue that for animals that live and forage in groups, level of sociality, reflecting differences in group size and cooperative tendencies, can be an additional and powerful dimension separating species in niche space. We compare 50+ communities of the social spider genus Anelosimus across the Americas against a null model that accounts for known effects of biotic and abiotic factors on the distribution of social systems in the genus. We show that these communities are more overdispersed than expected by chance in either or both body size and level of sociality, traits we have previously shown to be associated with differences in resource utilization (prey size, microhabitat, and phenology). We further show that the contribution of sociality to differences in the size of the prey captured is two to three times greater than that of body size, suggesting that changes in group size and cooperative tendencies may be more effective than changes in body size at separating species in niche space.

A Qualitative Study on Factors Modulating Tinnitus Experience.

OBJECTIVES: It is well recognized that tinnitus can severely interfere with important aspects of life such as sleep, concentration abilities, social activities, and mood. However, the impact of tinnitus may vary greatly from one individual to another, with some being severely affected and others only experiencing a slight handicap. Information from participants' experiences with tinnitus could help explain such variability. The full experience of living with tinnitus from a patient's perspective has been under-investigated, especially in comparison with the large and extensive body of qualitative research on hearing loss. This study aims to contribute to fill this gap and assess participants' experience of living with tinnitus. DESIGN: As part of a larger mixed design study, this inquiry used qualitative analyses to investigate participant's experiences with tinnitus. Twenty-seven tinnitus participants of different ages, sexes, audiometric profiles, and tinnitus severities were invited to discuss their tinnitus through semistructured interviews and journal entries. The interviews took place 1 month after participants completed a 3-week trial period with tinnitus maskers. RESULTS: The findings were grouped into three main themes: participants' appraisal of their tinnitus, factors modulating tinnitus experience, and consequences of tinnitus. Regarding participants' appraisal of their tinnitus, a dissociation between the tinnitus sensation (pitch, loudness) and tinnitus experience (annoyance/distress) was reported. Factors modulating tinnitus experience were classified as environmental factors and individual-specific factors, which were further divided into soundscape and other environmental factors for the former and attentional focus, stress level, physical state, fatigue, and auditory effort for the latter. Consequences of tinnitus included distraction, disrupted mental health and mood, headaches, fatigue, sleep disturbances, hearing difficulties, disrupted social life, and frustration. CONCLUSIONS: Two of the main themes (participants' appraisal of their tinnitus and consequences of tinnitus) were consistent with findings from a few previous qualitative studies. Factors modulating tinnitus experience also emerged as a prominent theme. Indeed, participants described a plethora of factors that affected their experiences of tinnitus. On the basis of these findings, an attentional model is proposed to account for how these factors might modulate the effects of tinnitus.

Reentry Tachycardia in Children: Adenosine Can Make It Worse.

OBJECTIVES: We report on a rare but severe complication of adenosine use in a child with reentry tachycardia. METHODS AND RESULTS: Treatment with adenosine, which is the standard medical therapy of atrioventricular reentry tachycardia, led to the development of an irregular wide complex tachycardia, caused by rapid ventricular response to atrial fibrillation. The girl was finally stabilized with electrical cardioversion. We analyze the pathomechanism and discuss possible treatment options. CONCLUSIONS: Atrial fibrillation, as well as its conduction to the ventricles, can be caused by adenosine. Rapid ventricular response in children with Wolff-Parkinson-White syndrome is more frequent than previously believed. A patient history of atrial fibrillation is a contraindication for cardioversion with adenosine and needs to be assessed in children with reentry tachycardia. High-risk patients may potentially profit from prophylactic comedication with antiarrhythmic agents, such as flecainide, ibutilide, or vernakalant, before adenosine administration.

Spodoptera frugiperda (Lepidoptera: Noctuidae) host-plant variants: two host strains or two distinct species?

The moth Spodoptera frugiperda is a well-known pest of crops throughout the Americas, which consists of two strains adapted to different host-plants: the first feeds preferentially on corn, cotton and sorghum whereas the second is more associated with rice and several pasture grasses. Though morphologically indistinguishable, they exhibit differences in their mating behavior, pheromone compositions, and show development variability according to the host-plant. Though the latter suggest that both strains are different species, this issue is still highly controversial because hybrids naturally occur in the wild, not to mention the discrepancies among published results concerning mating success between the two strains. In order to clarify the status of the two host-plant strains of S. frugiperda, we analyze features that possibly reflect the level of post-zygotic isolation: (1) first generation (F1) hybrid lethality and sterility; (2) patterns of meiotic segregation of hybrids in reciprocal second generation (F2), as compared to the meiosis of the two parental strains. We found a significant reduction of mating success in F1 in one direction of the cross and a high level of microsatellite markers showing transmission ratio distortion in the F2 progeny. Our results support the existence of post-zygotic reproductive isolation between the two laboratory strains and are in accordance with the marked level of genetic differentiation that was recovered between individuals of the two strains collected from the field. Altogether these results provide additional evidence in favor of a sibling species status for the two strains.

The auditory sensitivity is increased in tinnitus ears.

Increased auditory sensitivity, also called hyperacusis, is a pervasive complaint of people with tinnitus. The high prevalence of hyperacusis in tinnitus subjects suggests that both symptoms have a common origin. It has been suggested that they may result from a maladjusted increase of central gain attributable to sensory deafferentation. More specifically, tinnitus and hyperacusis could result from an increase of spontaneous and stimulus-induced activity, respectively. One prediction of this hypothesis is that auditory sensitivity should be increased in tinnitus compared with non-tinnitus subjects. The purpose of this study was to test this prediction by examining the loudness functions in tinnitus ears (n = 124) compared with non-tinnitus human ears (n = 106). Because tinnitus is often accompanied by hearing loss and that hearing loss makes it difficult to disentangle hypersensitivity (hyperacusis) to loudness recruitment, tinnitus and non-tinnitus ears were carefully matched for hearing loss. Our results show that auditory sensitivity is enhanced in tinnitus subjects compared with non-tinnitus subjects, including subjects with normal audiograms. We interpreted these findings as compatible with a maladaptive central gain in tinnitus.

Establishment and analysis of a reference transcriptome for Spodoptera frugiperda.

BACKGROUND: Spodoptera frugiperda (Noctuidae) is a major agricultural pest throughout the American continent. The highly polyphagous larvae are frequently devastating crops of importance such as corn, sorghum, cotton and grass. In addition, the Sf9 cell line, widely used in biochemistry for in vitro protein production, is derived from S. frugiperda tissues. Many research groups are using S. frugiperda as a model organism to investigate questions such as plant adaptation, pest behavior or resistance to pesticides. RESULTS: In this study, we constructed a reference transcriptome assembly (Sf_TR2012b) of RNA sequences obtained from more than 35 S. frugiperda developmental time-points and tissue samples. We assessed the quality of this reference transcriptome by annotating a ubiquitous gene family--ribosomal proteins--as well as gene families that have a more constrained spatio-temporal expression and are involved in development, immunity and olfaction. We also provide a time-course of expression that we used to characterize the transcriptional regulation of the gene families studied. CONCLUSION: We conclude that the Sf_TR2012b transcriptome is a valid reference transcriptome. While its reliability decreases for the detection and annotation of genes under strong transcriptional constraint we still recover a fair percentage of tissue-specific transcripts. That allowed us to explore the spatial and temporal expression of genes and to observe that some olfactory receptors are expressed in antennae and palps but also in other non related tissues such as fat bodies. Similarly, we observed an interesting interplay of gene families involved in immunity between fat bodies and antennae.

Successful twin pregnancy in a woman undergoing alternate diurnal and nocturnal hemodialysis.

Although pregnancy has become more frequent in patients undergoing hemodialysis, it remains a relatively rare event and carries a high risk of complications for both the mother and the fetus. In parallel, multiple pregnancies are also associated with a high risk of complications for the mother and the fetus, even in healthy women. The presence of a twin pregnancy in a woman with chronic renal failure undergoing hemodialysis is an even rarer event and is considered a very high-risk situation. We describe the case of a 31-year-old hemodialysis patient who successfully gave birth to twins at 29 weeks after a period of alternate diurnal and nocturnal hemodialysis.

Serum S100B Level in the Management of Pediatric Minor Head Trauma: A Randomized Clinical Trial.

Importance: Minor head trauma (HT) is one of the most common causes of hospitalization in children. A diagnostic test could prevent unnecessary hospitalizations and cranial computed tomographic (CCT) scans. Objective: To evaluate the effectiveness of serum S100B values in reducing exposure to CCT scans and in-hospital observation in children with minor HT. Design, Setting, and Participants: This multicenter, unblinded, prospective, interventional randomized clinical trial used a stepped-wedge cluster design to compare S100B biomonitoring and control groups at 11 centers in France. Participants included children and adolescents 16 years or younger (hereinafter referred to as children) admitted to the emergency department with minor HT. The enrollment period was November 1, 2016, to October 31, 2021, with a follow-up period of 1 month for each patient. Data were analyzed from March 7 to May 29, 2023, based on the modified intention-to-treat and per protocol populations. Interventions: Children in the control group had CCT scans or were hospitalized according to current recommendations. In the S100B biomonitoring group, blood sampling took place within 3 hours after minor HT, and management depended on serum S100B protein levels. If the S100B level was within the reference range according to age, the children were discharged from the emergency department. Otherwise, children were treated as in the control group. Main Outcomes and Measures: Proportion of CCT scans performed (absence or presence of CCT scan for each patient) in the 48 hours following minor HT. Results: A total of 2078 children were included: 926 in the control group and 1152 in the S100B biomonitoring group (1235 [59.4%] boys; median age, 3.2 [IQR, 1.0-8.5] years). Cranial CT scans were performed in 299 children (32.3%) in the control group and 112 (9.7%) in the S100B biomonitoring group. This difference of 23% (95% CI, 19%-26%) was not statistically significant (P = .44) due to an intraclass correlation coefficient of 0.32. A statistically significant 50% reduction in hospitalizations (95% CI, 47%-53%) was observed in the S100B biomonitoring group (479 [41.6%] vs 849 [91.7%]; P < .001). Conclusions and Relevance: In this randomized clinical trial of effectiveness of the serum S100B level in the management of pediatric minor HT, S100B biomonitoring yielded a reduction in the number of CCT scans and in-hospital observation when measured in accordance with the conditions defined by a clinical decision algorithm. Trial Registration: ClinicalTrials.gov Identifier: NCT02819778.

Improving Audiology Student Training by Clinical Simulation of Tinnitus: A Glimpse of the Lived Experience of Tinnitus.

PURPOSE: Student audiology training in tinnitus evaluation and management is heterogeneous and has been found to be insufficient. We designed a new clinical simulation laboratory for training students on psychoacoustic measurements of tinnitus: one student plays the role of the tinnitus patient, wearing a device producing a sound like tinnitus on one ear, while another student plays the role of the audiologist, evaluating their condition. The objective of the study was to test this new clinical simulation laboratory of tinnitus from the perspective of the students. METHOD: This study reports the findings from twenty-one audiology students (20 female and 1 male, mean age = 29, SD = 7.7) who participated in this laboratory for a mandatory audiology class at the Laval University of Quebec. Three students had hearing loss (one mild, two moderate). All students played the role of both the clinician and the patient, alternately. They also had to fill out a questionnaire about their overall experience of the laboratory. RESULTS: The qualitative analysis revealed three main themes: "Benefits of the laboratory on future practice", "Barriers and facilitators of the psychoacoustic assessment", and "Awareness of living with tinnitus". The participants reported that this experience would have a positive impact on their ability to manage tinnitus patients in their future career. CONCLUSION: This fast, cheap, and effective clinical simulation method could be used by audiology and other healthcare educators to strengthen students' skills and confidence in tinnitus evaluation and management. The protocol is made available to all interested parties.

Amplification of the poorer ear by StereoBiCROS in case of asymmetric sensorineural hearing loss: effect on tinnitus.

Tinnitus is prevalent among patients suffering from Single-Sided Deafness (SSD) and Asymmetrical Hearing Loss (AHL). In addition to bothersome tinnitus in the poorer ear, these patients also report issues with understanding speech in noise and sound localization. The conventional treatment options offered to these patients to improve auditory abilities are cochlear implantation, bone conduction devices or Contralateral Routing Of Signal (CROS) hearing aids. It was recently found that the benefit of cochlear implantation for tinnitus associated with AHL/SSD was greater than the other two approaches. It is conceivable that the lack of stimulation provided to the poorer ear in these last approaches explains their modest impact on tinnitus perception. A new technology that combines the ability to reroute the sound from the poorer ear to the good ear (CROS system) while still stimulating the poorer ear with conventional sound amplification has recently been developed: the StereoBiCROS system. The aim of this study was to investigate the effects of this new device on tinnitus. Twelve AHL and two SSD patients aged 70.7 ± 7.9 years with tinnitus were fitted with bilateral hearing aids that included 3 programs: Stereophonic, BiCROS and StereoBiCROS (CROS + bilateral amplification). The short-and long-term effect of the approach on tinnitus was assessed using a tinnitus Loudness Visual Analog Scale (VAS) and the Tinnitus Handicap Inventory (THI), respectively. Both the VAS and the THI were used before and one month after the hearing aid fitting. Of the 14 patients who used their hearing aids daily (12.6 ± 1.6 h per day) the StereoBiCROS program was the most used program (81.8 ± 20.5% of the time). The average THI total score decreased from 47 (± 22) to 15 (± 16) (p = 0.002) and the VAS-Loudness score decreased from 7 (± 1) to 2 (± 2) (p < 0.001) after the one-month trial period. In conclusion, StereoBiCROS stimulation strategy seems to offer an effective alternative to reduce tinnitus handicap and loudness for patients with AHL/SSD and tinnitus. This effect may be driven by sound amplification of the poorer ear.

Exploring the middle ear function in patients with a cluster of symptoms including tinnitus, hyperacusis, ear fullness and/or pain.

Middle ear muscle (MEM) abnormalities have been proposed to be involved in the development of ear-related symptoms such as tinnitus, hyperacusis, ear fullness, dizziness and/or otalgia. This cluster of symptoms have been called the Tonic Tensor Tympani Syndrome (TTTS) because of the supposed involvement of the tensor tympani muscle (TTM). However, the putative link between MEM dysfunction and the symptoms has not been proven yet and the detailed mechanisms (the causal chain) of TTTS are still elusive. It has been speculated that sudden loud sound (acoustic shock) may impair the functioning of the MEM, specifically the TTM, after an excessive contraction. This would result in inflammatory processes, activation of the trigeminal nerve and a change of the MEMs state into a hypersensitive one, that may be associated to the cluster of symptoms listed above. The goal of this study is to provide further insights into the mechanisms of TTTS. The middle ear function of 11 patients who reported TTTS symptoms has been investigated using either admittancemetry and/or measurement of air pressure in the sealed external auditory canal. While the former method measured the middle ear stiffness the latter provides an estimate of the tympanic membrane displacement. Most patients displayed results consistent with phasic contractions of the TTM (n = 9) and/or Eustachian Tube (ET) dysfunction (n = 6). The MEM contraction or ET dysfunction could be evoked by acoustic stimulation (n = 3), somatic maneuvers (n = 3), or pressure changes in the ear canal (n = 3). Spontaneous TTM contraction (n = 1) or ET opening (n = 1) could also be observed. Finally, voluntary contraction of MEM was also reported (n = 5). On the other hand, tonic contraction of the TTM could not be observed in any patient. The implications of these results for the mechanisms of TTTS are discussed.

Contraction of the stapedius and tensor tympani muscles explored by tympanometry and pressure measurement in the external auditory canal.

It has been suggested that tensor tympani muscle (TTM) contraction may be involved in the development of ear-related pathologies such as tinnitus, hyperacusis and otalgia, called the tonic tensor tympani syndrome (TTTS). However, as there is no precise measure of TTM function under normal and pathological states, its involvement remains speculative. When the TTM or the stapedius muscle (SM) contracts, they both generate an increase of middle ear stiffness that can be measured through middle ear admittance. However, this technique cannot differentiate the contraction between the two muscles. On the other hand, the air pressure measured in a sealed external auditory canal can provide a measure of the eardrum displacement that may be able to differentiate SM from TTM contraction. TTM is attached to the malleus, and its contraction causes a retraction of the eardrum inside the middle ear cavity, while SM can have a small but reversed effect on TTM displacement. To investigate this issue, we compared the middle ear admittance and air pressure in a sealed external ear canal upon auditory stimulation (sMEMC) and voluntary middle ear muscle contraction (vMEMC). In addition, we assessed the perceptual effect of vMEMC, including pitch and loudness matching of the fluttering noise produced by vMEMC and the threshold shifts, were measured. Out of the 14 ears tested, sMEMC was associated with a decrease of admittance in 93% (mean peak average: -0.06 ml, SD:0.04) and an increase of air pressure in 29% of ears (mean peak average: 8.1 Pa, SD:5.1). No decrease in air pressure was found upon sMEMC. For vMEMC (n = 8 ears), decreases were found for both admittance and air pressure in 100% and 88%, with a mean peak average of -0.38 ml, SD: 0.54 and -149 Pa, SD:156, for admittance and pressure respectively. These results suggest that SM and TTM are involved in sMEMC and vMEMC, respectively. In addition, vMEMC was associated with perceptual effects including a low-frequency sound, pitch-matched at ∼30 Hz (>15 dB SL), and a low-frequency hearing loss of at least 10 dB between 20 and 200 Hz. In conclusion, admittance and air pressure recordings provide useful and complementary information on middle ear muscle contraction and can be used to explore the middle ear function.

The gap prepulse inhibition of the acoustic startle (GPIAS) paradigm to assess auditory temporal processing: Monaural versus binaural presentation.

The Gap Prepulse Inhibition of the Acoustic Startle Reflex (GPIAS) is a paradigm used to assess auditory temporal processing in both animals and humans. It consists of the presentation of a silent gap embedded in noise and presented a few milliseconds before a startle sound. The silent gap produces the inhibition of the startle reflex, a phenomenon called gap-prepulse inhibition (GPI). This paradigm is also used to detect tinnitus in animal models. The lack of inhibition by the silent gaps is suggested to be indicative of the presence of tinnitus "filling-in" the gaps. The current research aims at improving the GPIAS technique by comparing the GPI produced by monaural versus binaural silent gaps in 29 normal-hearing subjects. Two gap durations (5 or 50 ms), each embedded in two different frequency backgrounds (centered around 500 or 4 kHz). Both low- and high- frequency narrowband noises had a bandwidth of half an octave. Overall, the startle magnitude was greater for the binaural versus the monaural presentation, which might reflect binaural loudness summation. In addition, the GPI was similar between the monaural and the binaural presentations for the high-frequency background noise. However, the GPI was greater for the low-frequency background noise for the binaural, compared to the monaural, presentation. These findings suggest that monaural GPIAS might be more suited to detect tinnitus compared to the binaural presentation.

A psychoacoustic test for diagnosing hyperacusis based on ratings of natural sounds.

Hyperacusis is defined as an increased sensitivity to sounds, i.e. sounds presented at moderate levels can produce discomfort or even pain. Existing diagnostic methods, like the Hyperacusis Questionnaire (HQ) and Loudness Discomfort Levels (LDLs), have been challenged because of their variability and lack of agreement on appropriate cut-off values. We propose a novel approach by using psychoacoustic ratings of natural sounds as an assessment tool for hyperacusis. Subjects (n = 81) were presented with natural and artificial (tone pips, noises) sounds (n = 69) in a controlled environment at four sound levels (60, 70, 80 and 90 dB SPL). The task was to rate them on a pleasant to unpleasant visual analog scale. The inherent challenge of this study was to create a new diagnostic tool when no gold standard of hyperacusis diagnosis exists. We labeled our subjects as hyperacusic (n = 26) when they were diagnosed as such by at least two of three methods (HQ, LDLs and self-report). There was a significant difference between controls (n = 23) and hyperacusics in the median global rating of pleasant sounds. Median global ratings of unpleasant sounds and artificial sounds did not differ significantly. Then we selected the subset of sounds that could best discriminate the controls from the hyperacusics, the Core Discriminant Sounds (CDS), and we used them to develop a new metric: The CDS score. A normalized global score and a score for each sound level can be computed with respect to a control population without hyperacusis. A receiver operating characteristic analysis showed that the accuracy of our method in distinguishing subjects with and without complaints of hyperacusis (86%, 95% Confidence Interval (CI): 76-93%) is comparable to that of existing methods such as the LDL (77%, CI: 67-86%) and the HQ (80%, CI: 69-88%). We believe that the CDS score is more relevant to subject's complaints than LDLs and that it could be applied in a clinical environment in a fast and effective way, while minimizing discomfort and biases.

The difference in poststimulus suppression between residual inhibition and forward masking.

The phenomenon of tinnitus masking (TM) and residual inhibition (RI) of tinnitus are two ways to investigate how external sounds interact with tinnitus: TM provides insight on the fusion between external sound activity and tinnitus related activity while RI provides insight on how the external sound might suppress the tinnitus related activity for a period of time. Differences in masking level between the tinnitus and an external tone with tinnitus characteristics (frequency, loudness) have previously shown a high level of heterogeneity. The difference in poststimulus suppression between the two, that is, residual inhibition for the former, and forward masking for the latter, has never been explored. This study aims to investigate minimum masking levels (MMLs) and minimum residual inhibition levels (MRILs) of tinnitus and of an external tone mimicking tinnitus while using diotic and dichotic noises. Pulsed narrowband noises (1 octave width and centered at 1kHz, frequency of the hearing loss slope, tinnitus frequency) and white noise were randomly presented to 20 tinnitus participants and 20 controls with an external tone mimicking tinnitus (4kHz, intensity level corresponding to tinnitus loudness). The MML values obtained for the masking of tinnitus and for the mimicking external sounds were very similar. On the other hand, the MRILs were significantly different between the tinnitus and the mimicking external sounds within tinnitus participants. They were also different between the tinnitus participants and the controls. Overall, for both within and between comparisons, the MRIL values were much higher to produce a poststimulus suppression for the mimicking sound than for the tinnitus. The results showed no significant differences between the diotic and dichotic conditions. These results corroborate other findings suggesting that the tinnitus-related neural activity is very different from the stimulus-related neural activity. The consequences of this last finding are discussed.

A psychoacoustic test for misophonia assessment.

Misophonia is a condition where a strong arousal response is triggered when hearing specific human generated sounds, like chewing, and/or repetitive tapping noises, like pen clicking. It is diagnosed with clinical interviews and questionnaires since no psychoacoustic tools exist to assess its presence. The present study was aimed at developing and testing a new assessment tool for misophonia. The method was inspired by an approach we have recently developed for hyperacusis. It consisted of presenting subjects (n = 253) with misophonic, pleasant, and unpleasant sounds in an online experiment. The task was to rate them on a pleasant to unpleasant visual analog scale. Subjects were labeled as misophonics (n = 78) or controls (n = 55) by using self-report questions and a misophonia questionnaire, the MisoQuest. There was a significant difference between controls and misophonics in the median global rating of misophonic sounds. On the other hand, median global rating of unpleasant, and pleasant sounds did not differ significantly. We selected a subset of the misophonic sounds to form the core discriminant sounds of misophonia (CDSMiso). A metric: the CDS score, was used to quantitatively measure misophonia, both with a global score and with subscores. The latter could specifically quantify aversion towards different sound sources/events, i.e., mouth, breathing/nose, throat, and repetitive sounds. A receiver operating characteristic analysis showed that the method accurately classified subjects with and without misophonia (accuracy = 91%). The present study suggests that the psychoacoustic test we have developed can be used to assess misophonia reliably and quickly.

Modulation of hyperacusis and tinnitus loudness in tinnitus patients with and without hearing loss following 3 weeks of acoustic stimulation: A proof-of-concept study.

Tinnitus and hyperacusis are two debilitating conditions that are highly comorbid. It has been postulated that they may originate from similar pathophysiological mechanisms such as an increase in central gain. Interestingly, sound stimulation has been shown to reduce central gain and is currently used for the treatment of both conditions. This study investigates the effect of sound stimulation on both tinnitus and hyperacusis in the same patients. Two distinct series of tinnitus participants were tested: one with normal or near-normal hearing (n=16) and one with hearing loss (n=14). A broadband noise shaped to cover most of the tinnitus frequency spectrum was delivered through hearing aids using the noise generator feature (no amplification) and verified through real-ear measurements. Participants received sound stimulation for 3 weeks and were tested before (at baseline), then after 1 week and at the end of the 3 weeks of sound stimulation. There was also a 1-month follow-up after the end of the stimulation protocol. The measurements included self-reported measures of tinnitus and hyperacusis (VAS), validated questionnaires (THI, HQ) and psychoacoustic measurements (tinnitus battery and loudness functions). On both self-assessment (VAS of sound tolerance and tinnitus loudness) and psychoacoustic measures (loudness function and tinnitus loudness in dB), about 50% of tinnitus participants had a synchronous (either a decrease or an increase) modulation of hyperacusis and tinnitus loudness after 1 week and 3 weeks of acoustic stimulation and up to about 70% of participants at 1-M follow-up. The decrease of hyperacusis and tinnitus loudness was more prevalent in normal-hearing participants. There was a significant increase in tinnitus loudness during and following the stimulation in the group with hearing loss. Hyperacusis improvement as assessed by loudness function was significantly correlated with the intensity level of the acoustic stimulation (dB level of the noise produced by the noise generator) in tinnitus participants with normal/near-normal hearing thresholds. Our study partly supports the central gain hypothesis by showing synchronous modulation of hyperacusis and tinnitus loudness. It also shows beneficial effects of acoustic stimulation in some tinnitus individuals, in particular those with normal or near-normal hearing, while highlighting the importance of a careful fitting of sound generators to prevent increase. Since the amplification feature was not turned on in our study, future work should determine whether amplification alone, or in addition to acoustic stimulation (sound generators), would benefit to those with hearing loss.

A contribution to the debate on tinnitus definition.

Tinnitus is generally defined as an auditory perception in the absence of environmental sound stimulation. However, this definition is quite incomplete as it omits an essential aspect, the patient's point of view. This point of view constitutes, first and foremost, a global and unified lived experience, which is not only sensory (localization, loudness, pitch and tone), but also cognitive (thoughts, attentiveness, behaviors) and emotional (discomfort, suffering). This experience can be lived in a very unpleasant way and consequently have a very negative impact on quality of life. This article proposes and justifies a new definition for tinnitus elaborated by a group of French clinicians and researchers, which is more in line with its phenomenology. It also provides a minimum knowledge base, including possibilities for clinical care, hoping to eradicate all misinformation, misconceptions and inappropriate attitudes or practices toward this condition. Here is the short version of our definition: Tinnitus is an auditory sensation without an external sound stimulation or meaning, which can be lived as an unpleasant experience, possibly impacting quality of life.