Brain-derived neurotrophic factor (BDNF) has a crucial function in the central nervous system and in sensory structures including olfactory and auditory systems. Many studies have highlighted the protective effects of BDNF in the brain, showing how it can promote neuronal growth and survival and modulate synaptic plasticity. On the other hand, conflicting data about BDNF expression and functions in the cochlear and in olfactory structures have been reported. Several clinical and experimental research studies showed alterations in BDNF levels in neurodegenerative diseases affecting the central and peripheral nervous system, suggesting that BDNF can be a promising biomarker in most neurodegenerative conditions, including Alzheimer’s disease, shearing loss, or olfactory impairment. Here, we summarize current research concerning BDNF functions in brain and in sensory domains (olfaction and hearing), focusing on the effects of the BDNF/TrkB signalling pathway activation in both physiological and pathological conditions. Finally, we review significant studies highlighting the possibility to target BDNF as a biomarker in early diagnosis of sensory and cognitive neurodegeneration, opening new opportunities to develop effective therapeutic strategies aimed to counteract neurodegeneration.

Permanent childhood hearing impairment (PCHI) represents the most frequent sensory pathology at birth. PCHI has a relevant psychological impact on the life of both the affected children and their families. Thus, the aim of this work is to explore the degree of parental distress felt by mothers of a deaf or hard-of-hearing child, to determine if this stress is associated with variables related to the children’s health (e.g., the severity of hearing loss, presence of other conditions, difficulty with treatment options, difficulty with rehabilitation) or family characteristics such as socio-economic and educational status. The study used the Parenting Stress Index–Short Form (PSI-SF) questionnaire administered to mothers. The results were analyzed in relation to variables such as parents’ education level, number of children, severity of hearing loss, presence of other chronic conditions, presence of cognitive delay, familiarity with hearing loss, time of diagnosis, use of prosthetics, and start in a rehabilitation program. The data indicate a correlation between maternal stress levels and low-educational levels, as well as the presence of congenital infections and cognitive delay. These results highlight the need for a comprehensive physical and psychological approach for hearing-impaired children, as stress factors can affect the adherence to effective rehabilitation.

Introduction: Tinnitus is a common and disabling symptom often associated with hearing loss. While clinical practice frequently shows that a certain degree of psychological discomfort often characterizes tinnitus suffers, it has been recently suggested in adults as a determining factor for cognitive decline affecting attention and memory domains. The aim of our systematic review was to provide evidence for a link between tinnitus, psychological distress, and cognitive dysfunction in older patients and to focus on putative mechanisms of this relationship. Methods: We performed a systematic review, finally including 192 articles that were screened. This resulted in 12 manuscripts of which the full texts were included in a qualitative analysis. Results: The association between tinnitus and psychological distress, mainly depression, has been demonstrated in older patients, although only few studies addressed the aged population. Limited studies on cognitive dysfunction in aged patients affected by chronic tinnitus are hardly comparable, as they use different methods to validate cognitive impairment. Actual evidence does not allow us with certainty to establish if tinnitus matters as an independent risk factor for cognitive impairment or evolution to dementia. Conclusion: Tinnitus, which is usually associated with age-related hearing loss, might negatively affect emotional wellbeing and cognitive capacities in older people, but further studies are required to improve the evidence.

Sensorineural hearing impairment is a common pathological manifestation in patients affected by X-linked intellectual disability. A few cases of interstitial deletions at Xq21 with several different phenotypic characteristics have been described, but to date, a complete molecular characterization of the deletions harboring disease-causing genes is still missing. Thus, the aim of this study is to realize a detailed clinical and molecular analysis of a family affected by syndromic X-linked hearing loss with intellectual disability. Clinical analyses revealed a very complex phenotype that included inner ear malformations, vestibular problems, choroideremia and hypotonia with a peculiar pattern of phenotypic variability. Genomic analysis revealed, for the first time, the presence of two close interstitial deletions in the Xq21.1-21.3, harboring 11 protein coding, 9 non-coding genes and 19 pseudogenes. Among these, 3 protein coding genes have already been associated with X-linked hearing loss, intellectual disability and choroideremia. In this study we highlighted the presence of peculiar genotypic and phenotypic details in a family affected by syndromic X-linked hearing loss with intellectual disability. We identified two, previously unreported, Xq21.1-21.3 interstitial deletions. The two rearrangements, containing several genes, segregate with the clinical features, suggesting their role in the pathogenicity. However, not all the observed phenotypic features can be clearly associated with the known genes thus, further study is necessary to determine regions involved.

Background/Objectives: Bimodal stimulation (BS), which combines the use of a cochlear implant (CI) in one ear and a hearing aid (HA) in the opposite ear, is an established strategy to treat hearing loss by exploiting the unique capabilities of each device. CIs stimulate the auditory nerve by bypassing damaged hair cells, while HAs amplify sounds by requiring a functional hearing residual. The aim of this systematic review is to investigate the advantages and disadvantages of BS such as speech perception in noise. Methods: We examined clinical studies published from October 2020 to July 2024, following the PRISMA guidelines, focusing on the advantages and disadvantages of BS on speech perception in noise in adulthood. Results: BS in adult patients significantly improves speech perception in quiet and noisy environments, especially for those with increased residual hearing. Unilateral CIs and BS perform similarly in quiet conditions, but BS significantly improves speech discrimination in noisy environments if loudness between the two devices is appropriately balanced. Conclusions: Directional microphones and programming software are new technologies that succeed in reducing environmental noise and improving verbal perception outcomes, although their features in the literature are controversial. In addition, the individuals using BS may face temporal mismatches mainly due to differing device latencies, affecting sound localization. Compensating for these mismatches can enhance localization accuracy. However, modulated noise remains a significant obstacle to verbal perception in noise. Valuable assessment tools such as music tests provide further information on hearing performance and quality of life. More research is needed to define certain selection criteria.

Background: An early hearing detection and intervention program (EHDI) is the first step for the habilitation of children with permanent hearing impairment (PHI). Actually, early intervention programs have increasingly shifted toward family involvement, emphasizing that the child’s family should take an active role in the habilitation process. Therefore, familiar empowerment is the best way to improve a child’s emerging abilities. The aim of this study was to investigate parental self-efficacy beliefs and involvement as well as the language skills of deaf or hard of hearing DHH children who were habilitated with hearing aids and followed using the T.A.T.A web app (NeonaTal Assisted TelerehAbilitation), an example of asynchronous telepractice. Methods: The study describes the early stages of the habilitation program of 15 PHI children followed through the T.A.T.A. web app, which empowers families through a weekly questionnaire submitted during the first 270 to 360 days of their child’s life, for 14 weeks. The family involvement rate scale (FIRS) was used to evaluate parental compliance, and all children received in-person visits at the beginning and at the end of the training period. Results: The children showed greater auditory perceptual skills at the end of the training period on the basis of both the Infant Listening Progress Profile (ILiP) score and the Categories of Auditory Performance (CAP) and FIRS scales. In other words, the auditory skills improved with age as well as with parental participation. Conclusions: The T.A.T.A. web app promotes a proactive management and a tailored habilitation through an active familiar involvement, easily achieved in clinical routine and in emergency settings without additional costs.