Background: Serotonin (5-HT) is a neurotransmitter and a hormone that regulates various functions. Serotonin receptors have been studied in animal experiments in the vestibular system, beginning from the inner ear and vestibular nuclei. However, the role of serotonin in the vestibular system and disorders remains to be clarified. Methods: A review of the literature was performed on different databases according to the PRISMA guidelines. Only publications published on humans and in English have been included. A total of 41 articles were included in this review. Results: There are many publications regarding the use of SSRI/SNRI in vestibular disorders. Regarding persistent postural perceptual dizziness (PPPD) and chronic subjective dizziness (CSD) the available evidence supports multimodality treatment incorporating vestibular rehabilitation, serotonergic medications, and cognitive behavior therapy, although most studies have not included a placebo control group. As for vestibular migraine (VM), SNRI and SSRIs were proposed as preventive therapy and demonstrated a reduction in vertigo attacks in patients with Menière’s Disease (MD), especially when symptoms of anxiety disorder were present. Conclusions: Although SSRIs/SNRIs are considered an off-label therapy for vertigo, several studies have assessed their efficacy in vestibular disorders, as indicated in the data published on PPPD, MD, and VM above all. As some studies report that serotonin receptors are also present in the inner ear and vestibular nuclei, it can be postulated that in cases where the natural levels of serotonin are altered, such as in depression and anxiety, the change in serotonin levels may affect vestibular function and play a role in vestibular disorders.

Background/Objectives: Tinnitus is a complex auditory phenomenon with multifactorial origins, often involving both peripheral and central auditory pathways. Given the multifactorial nature of tinnitus, this review specifically focuses on the auditory brainstem as it represents the first central relay for auditory input and a key site of abnormal synchrony and central gain, which may generate or modulate tinnitus even when peripheral hearing appears normal. Several studies suggest a potential role of brainstem dysfunction in its pathogenesis, even among patients with normal hearing thresholds. Although the physiopathological data provide evidence for the role of brainstem in the generation and magnification of tinnitus, the diagnostic tools are still unclear. This systematic review aimed to investigate the diagnostic relevance of brainstem-level abnormalities in individuals with tinnitus. Methods: Following PRISMA guidelines, a literature search was conducted using PubMed, Scopus, and Web of Science from January 2000 to June 2025. Studies were included if they addressed the diagnostic relationship between tinnitus and brainstem involvement. Data on auditory brainstem response (ABR), otoacoustic emissions (used to differentiate peripheral from central auditory abnormalities), neuroimaging, and electrophysiological markers were extracted. Results: Twenty studies were included. Most used ABR as a diagnostic tool, revealing significant amplitude and latency alterations in tinnitus patients compared to controls, particularly in wave V and V/I amplitude ratios. Imaging studies supported altered brainstem–cortical connectivity and localized changes in inferior colliculus (IC) activity. Additional techniques, such as middle-latency evoked potentials and gap-in-noise detection, showed potential but lacked consistent clinical utility. Conclusions: Evidence suggests that brainstem dysfunction may contribute to tinnitus generation or persistence. ABR and advanced imaging represent specific diagnostic tools, though standardization and high-quality studies are still needed to improve clinical applicability.

The brainstem plays a pivotal role in the generation and control of eye movements—including saccades, smooth pursuit, the vestibulo-ocular reflex (VOR), vergence, and gaze holding. Beyond its vital physiological functions, it is also essential for the coordination of balance and movement. Consequently, eye movement disorders of brainstem origin are often accompanied by vertigo, imbalance, unsteady gait, and diplopia, particularly during changes in head or body position. A sound understanding of the neural structures involved in oculomotor and vestibular control is therefore crucial for accurately identifying and localizing a wide variety of brainstem syndromes. However, oculomotor abnormalities resulting from brainstem disease represent a major diagnostic challenge for the neurotologist, owing to the wide spectrum of possible etiologies (vascular, traumatic, degenerative, neoplastic), their variable severity and clinical course (acute, fluctuating, or progressive), and the frequent concomitant involvement of other central structures, particularly the cerebellum. This mini review summarizes the pathophysiological mechanisms and clinical features of oculomotor disorders and nystagmus associated with brainstem disease.

Background/Objectives: Cochlear implants (CIs) are a common treatment of severe-to-profound hearing loss and provide reasonable speech understanding, at least in quiet situations. However, their limited spectro-temporal resolution restricts sound quality, which is especially crucial for music appraisal. Many CI recipients wear a hearing aid (HA) on the non-implanted ear (bimodal users), which may enhance music perception by adding acoustic fine structure cues. Since it is unclear how the HA should be fitted in conjunction with the CI to achieve optimal benefit, this study aimed to systematically vary HA fitting parameters and assess their impact on music sound quality in bimodal users. Methods: Thirteen bimodal CI recipients participated in a listening experiment using a master hearing aid that allowed controlled manipulation of HA settings. Participants evaluated three music excerpts (pop with vocals, pop without vocals, classical) using the multiple-stimulus with hidden reference and anchor (MUSHRA) test. To assess the reliability of individual judgments, each participant repeated the test, and responses were analyzed with the eGauge method. Results: Most participants provided reliable and consistent sound quality ratings. Compared to a standard DSL v5.0 prescriptive fitting, modifications in compression settings and low-frequency gain significantly influenced perceived music quality. The effect of low-frequency gain adjustments was especially pronounced for pop music with vocals, indicating stimulus-dependent benefits. Conclusions: The study demonstrates that HA fitting for bimodal CI users can be optimized beyond standard prescriptive rules to enhance music sound quality by increasing low-frequency gain, particularly for vocal-rich pieces. Additionally, the testing method shows promise for clinical application, enabling individualized HA adjustments based on patient-specific listening preferences, hence fostering personalized audiology care.

Background/Objectives: Shift work in healthcare professionals affects performance in high cognitive processing, especially in complex environments. However, the beneficial effects that working in complex environments may have on auditory–cognitive processing remain unknown. These professionals face increased challenges in decision-making due to factors such as noise exposure and sleep disturbances, which may lead to the development of enhanced auditory–cognitive resources. This study aims to investigate the associations between shift work and auditory–cognitive processing in middle-aged healthcare workers. Methods: Thirty middle-aged healthcare workers were equally allocated to a shift worker (SW) or a fixed-schedule worker (FSW) group. Performance on a cognitive test, and in pure-tone audiometry, speech in quiet and noise, and listening effort were used to explore whether correlations were specific to shift work. Results: Exploratory analyses indicated that shift workers tended to perform better in visuospatial/executive function, memory recall, memory index, orientation, and total MoCA score domains compared to fixed-schedule workers. In the SW group, hearing thresholds correlated with memory recall and memory index. In the FSW group, hearing thresholds correlated with orientation, memory index, and total MoCA score, while listening effort correlated with naming, and speech intelligibility in quiet correlated with total MoCA scores. Conclusions: These exploratory findings suggest that shift work may be linked to distinct auditory–cognitive patterns, with potential compensatory mechanisms in visuospatial/executive functions and memory among middle-aged healthcare workers. Larger, longitudinal studies are warranted to confirm whether these patterns reflect true adaptive mechanisms.

Background/Objectives: For most adults receiving a cochlear implant (CI), the primary goal is to enhance their oral communication with others. The aim of this study was to investigate the total CI usage time per day among retired CI users and to characterize in which auditory environments they were using their CI. One additional aim was to analyze whether usage time, auditory environment, or social factors influenced CI speech perception. Methods: Participants completed a questionnaire addressing retirement status, whether they lived with another adult, educational level, and participation in social activities. Speech perception scores were obtained from medical records, and CI datalogging was extracted from the CI programming software. Results: Seventy-three CI users aged >65 years were included. The average usage was 12.9 h/day. No statistically significant correlations were found between total usage time or time spent listening to speech and CI speech perception. CI users who regularly met with family or friends had statistically significantly higher CI speech perception than those who did not (p = 0.003). Conclusions: Social interaction may play a crucial role in supporting speech perception among elderly CI users. Opportunities for communication and participation in social life appear to be important for maximizing benefit.

Background/Objectives: The Eustachian tube (ET) is a physiological channel connecting the middle ear with the external atmosphere. The ET plays a role in maintaining the pressure balance of the middle ear, protecting it from pathogen invasion, and cleaning secretions. Eustachian tube dysfunction (ETD) can lead to middle ear diseases in animals. The ET morphological structure are different across species. Therefore, we aim to compare the anatomical and morphological of ET across species. Methods: The combined skull base–nasal approach was used to anatomy ET. Hematoxylin-eosin, luxol fast blue myelin and immunohistochemical Staining were used to observe the morphology of ET. Results: There were significant differences in the size and structure of ET among species: the rodents ET (mouse: 1.152 ± 0.084 mm; rat: 3.738 ± 0.04355 mm) is characterized by cartilage and obvious bubbles; while the miniature pigs ET (32.34 ± 2.157 mm) has a chondroid conical structure similar to that of humans. ET inflammation model was built by intro-tympanic injection of lipopolysaccharide (LPS). NADPH oxidase 2 (NOX2) significantly increased by 38.6% in inflamed mice, causing ET oxidative stress. The expressions of inflammatory factors interleukin-1β (IL-1β) and cyclooxygenase-2 (COX2) increased by 28.4% and 30.8%, resulting in thickening of the ET mucosa and infiltration of inflammatory cells. Conclusions: The combined skull base–nasal approach was an effective method to anatomy ET across species. The morphology of ET varied across species and NOX2 might play an important role in ET inflammation.

Background/Objectives: Audiometric methods for hearing-impaired patients are constantly evolving as new therapeutic interventions and improved clinical standards are established. This study aimed to explore the relationship between patient-reported outcome measures in cochlear implant users and scores from audiometric test procedures in quiet and noise. Methods: In a prospective study, 20 postlingually deafened CI users were included. Speech comprehension was measured in quiet (by Freiburg words) and in noise (by the Oldenburg sentence test), while stationary speech-simulating or temporally fluctuating noise was applied and the noise sources were varied. Subjective feedback from the patients was obtained using the HISQUI19 questionnaire. Results: Word scores in quiet showed a significant positive correlation with the user’s subjective assessment of hearing ability using the questionnaire (Spearman’s R = 0.57). A greater correlation of the subjective evaluation of comprehension against fluctuating background noise as compared with stationary background noise was evident. On the other hand, the test–retest accuracy was reduced by a substantial factor in the transition from stationary to fluctuating background noise. Conclusions: By introducing temporal fluctuations in the background noise, the ecological validity can be improved, but at the cost of a parallel decrease in the accuracy of the test procedure. Especially in the context of studies, this knowledge may help to improve the choice of the specific test method used in evaluating the relationship between ecological validity and precision audiometry.

Objectives: Typical BPPV forms are widespread and easily diagnosed disorders. However, some forms of labyrinthine lithiasis can differ from the typical BPPV paradigm, showing their own signs and symptoms and resulting in variable therapeutic responses. The aim of this retrospective study is to describe the incidence of the so-called atypical forms compared to the more common BPPV, describing their clinical behavior. Methods: This retrospective study analyzed clinical and instrumental data of 139 patients evaluated over a 12-month period at a referral center. Patients were divided into two groups. The first group (Group A) included patients with so-called “typical” and unilateral labyrintholithiasis, while the second group (Group B) included patients with so-called “atypical” forms. Results: Based on clinical characteristics, 82 patients were assigned to group A while 57 (51.01%) to group B. In group A, resolution of the clinical picture required fewer sessions and a smaller number of therapeutic maneuvers than in group B (p < 0.001). Furthermore, in group A, resolution of symptoms was observed immediately after one of the therapeutic maneuvers performed in 74.07% of cases, while in group B, resolution of the clinical picture was observed during one of the follow-up visits in 39.66% of cases (p < 0.001). Conclusions: Although considered rare, “atypical” forms have an increased prevalence in tertiary centers. The location of the canaliths within the labyrinth can be hypothesized based on the pattern of nystagmus, which serves as a guide for treatment.

Background/Objectives: Cytomegalovirus (CMV)-associated hearing loss is common in non-genetic congenital hearing loss. Despite this high prevalence, a wide range of clinical characteristics exists, and the pattern of hearing loss remains unknown. This study aims to describe the clinical manifestations in children with CMV-associated hearing loss and to clarify the timing of hearing level change and the degree of hearing level fluctuation. Methods: A total of 54 patients with hearing loss due to congenital CMV infection were included. Hearing loss type (congenital or later onset), hearing loss laterality (unilateral or bilateral), severity at first and last visit, hearing progression and timing, and the difference between patients with intellectual disability and without intellectual disability were assessed. Results: The number of patients with congenital hearing loss and later onset hearing loss were 19 patients and 13 patients, respectively. Seventy-four percent (14/19) of the congenital hearing loss patients and 62% (8/13) of the later onset hearing loss patients eventually progressed to severe to profound hearing loss bilaterally. Progression occurred in less than 1 year (9 cases), between 1 and 3 years (7 cases), between 3 and 7 years (4 cases), or more than 8 years (1 case). Multiple progression events occurred in 11 cases. Conclusions: Sixty-one percent of patients had progression of hearing loss. Several cases experienced progression over more than one year and showed multiple progression events. CMV patients without intellectual disability tended to suffer later onset hearing loss. Sixty-nine percent of the patients eventually progressed to bilateral severe to profound hearing loss, which means that continuous long-term follow-up is required.