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Advances in Oto-rhino-laryngology 2018The functional changes that occur in the brain due to deafness may affect the way the auditory system processes sound after cochlear implantation. Brain plasticity plays... (Review)
Review
The functional changes that occur in the brain due to deafness may affect the way the auditory system processes sound after cochlear implantation. Brain plasticity plays a crucial role in the success of cochlear implantation to facilitate or develop spoken language in profoundly deaf individuals. The functional plasticity that occurs in postlingually deaf adults during periods of deafness can both support and hinder speech understanding with a cochlear implant, depending on the nature and degree of functional changes. Evidence so far suggests that the strategies people use to communicate while deaf may influence whether the functional changes are adaptive or maladaptive. In the case of children with congenital deafness, evidence is very strong for a sensitive period in which auditory input must be restored if subsequent oral language is to be developed successfully. Successful oral language use and speech understanding in individuals implanted after 7 years of age depends strongly on the pre-implant use of hearing aids and auditory-verbal communication. Future research should focus on how to harness our growing knowledge of brain plasticity to optimize the outcomes of cochlear implantation in each individual.
Topics: Adult; Brain; Child; Cochlear Implantation; Cochlear Implants; Deafness; Humans; Neuronal Plasticity
PubMed: 29794427
DOI: 10.1159/000485586 -
American Annals of the Deaf 2017Responding to an article by Grushkin on how deaf children best learn to read, published, along with the present article, in an American Annals of the Deaf special issue,... (Review)
Review
Responding to an article by Grushkin on how deaf children best learn to read, published, along with the present article, in an American Annals of the Deaf special issue, the authors review American Sign Language gloss. Topics include how ASL gloss enables deaf children to learn to read in their own language and simultaneously experience a transition to written English, and what gloss looks like and how it underlines deaf children's learning and mastery of English literacy through ASL. Rebuttal of Grushkin's argument includes data describing a deaf child's engagement in reading aloud (entirely in ASL) with a gloss text, which occurred without the breakdown implied by Grushkin. The authors characterize Grushkin's argument that deaf children need to learn to read through a conventional ASL writing system as limiting, asserting that ASL gloss contributes more by providing a path for learning and mastering English literacy.
Topics: Adolescent; Child; Child Language; Child, Preschool; Comprehension; Deafness; Education of Hearing Disabled; Humans; Linguistics; Literacy; Persons With Hearing Impairments; Reading; Sign Language; Writing
PubMed: 28238974
DOI: 10.1353/aad.2017.0004 -
JAMA Otolaryngology-- Head & Neck... Oct 2020
Review
Topics: Cochlear Implantation; Deafness; Hearing Loss, Unilateral; Humans; Speech Perception
PubMed: 32857123
DOI: 10.1001/jamaoto.2020.2287 -
American Journal of Audiology Jun 2021Background It is unknown whether hospital outcomes differ among nonspeaking deaf patients compared to those without this disability. Objective This article aims to...
Background It is unknown whether hospital outcomes differ among nonspeaking deaf patients compared to those without this disability. Objective This article aims to compare clinical outcomes and utilization data among patients with and without deafness. Design This study used a retrospective cohort study. Setting and Participants The participants included Nationwide Inpatient Sample, year 2017, hospitalized adults with and without diagnostic codes related to deafness and inability to speak. Method Multiple logistic and linear regression were used to compare in-hospital outcomes. Results Thirty million four hundred one thousand one hundred seventeen adults were hospitalized, and 7,180 had deafness and inability to speak related coding. Patients with deafness were older (mean age ± : 59.2 ± 0.51 vs. 57.9 ± 0.09 years, = .01), and less likely female (47.0% vs. 57.7%, < .01) compared to controls. Those with deafness had more comorbidities compared to the controls (Charlson comorbidity score ≥ 3: 31.2% vs. 27.8%, < .01). Mortality was higher among deaf versus controls (3.6% vs. 2.2%; < .01); this translated into higher adjusted odds of mortality (adjusted odds ratio = 1.7. [confidence interval (CI) 1.3-2.4]; = .01). Deaf patients had lower odds of being discharged home compared to controls {aOR} = 0.6, (CI) 0.55-0.73]; < .01. Length of stay was longer (adjusted mean difference = 1.5 days CI [0.7-2.3]; < .01) and hospital charges were higher, but not significantly so (adjusted mean difference = $4,193 CI [-$1,935-$10,322]; = .18) in patients with deafness. Conclusions Hospitalized nonspeaking deaf patients had higher mortality and longer hospital stays compared to those without this condition. These results suggest that specialized attention may be warranted when deaf patients are admitted to our hospitals in hopes of reducing disparities in outcomes. Supplemental Material https://doi.org/10.23641/asha.14336663.
Topics: Adult; Deafness; Female; Hospital Mortality; Hospitalization; Humans; Length of Stay; Retrospective Studies; United States
PubMed: 33823115
DOI: 10.1044/2021_AJA-20-00156 -
Neural Plasticity 2018Deafness is a common human disease, which is mainly caused by irreversible damage to hair cells and spiral ganglion neurons (SGNs) in the mammalian cochlea. At present,... (Review)
Review
Deafness is a common human disease, which is mainly caused by irreversible damage to hair cells and spiral ganglion neurons (SGNs) in the mammalian cochlea. At present, replacement of damaged or missing hair cells and SGNs by stem cell transplantation therapy is an effective treatment. However, the survival rate of stem cell transplantation is low, with uncontrollable differentiation hindering its application. Most researchers have focused on biochemical factors to regulate the growth and differentiation of stem cells, whereas little study has been performed using physical factors. This review intends to illustrate the current problems in stem cell-based treatment against deafness and to introduce electric field stimulation as a physical factor to regulate stem cell behavior and facilitate stem cell therapy to treat hearing loss in the future.
Topics: Animals; Combined Modality Therapy; Deafness; Electric Stimulation Therapy; Hair Cells, Auditory; Humans; Regeneration; Stem Cell Transplantation
PubMed: 29853854
DOI: 10.1155/2018/9506387 -
EMBO Molecular Medicine Apr 2024Approximately half a billion people—5% of the world’s population—suffer from disabling hearing impairment (HI) according to the WHO...
Approximately half a billion people—5% of the world’s population—suffer from disabling hearing impairment (HI) according to the WHO (http://www.who.int/features/factfiles/deafness/en/). HI commonly hampers speech acquisition, leads to social isolation and increases risk for depression and cognitive decline. One to two per thousand children are born with disabling HI and over 50% of sensorineural HI is caused by defects in individual genes (deafness genes) of which roughly 150 have been identified so far (http://hereditaryhearingloss.org/). In case of profound hearing impairment or deafness, cochlear implants that bypass the dysfunctional or lost sensory hair cells and electrically stimulate the auditory nerve partially restore hearing. However, hearing with cochlear implants has shortcomings such as limited understanding of speech in background noise. So, there remains a major unmet medical need for improved hearing restoration (Wolf et al, 2022). Yet, despite major research efforts, a causal treatment based on pharmacology, gene therapy, or stem cells had, so far, not been clinically available. Now, this is finally changing at least for some patients: first in human trials prove the concept for inner ear gene therapy of otoferlin-related synaptic deafness.
Topics: Humans; Deafness; Genetic Therapy
PubMed: 38528140
DOI: 10.1038/s44321-024-00058-6 -
Hearing Research Jan 2017The theory of predictive coding assumes that higher-order representations influence lower-order representations by generating predictions about sensory input. In... (Review)
Review
The theory of predictive coding assumes that higher-order representations influence lower-order representations by generating predictions about sensory input. In congenital deafness, one identified dysfunction is a reduced activation of deep layers in the auditory cortex. Since these layers play a central role for processing top-down influences, congenital deafness might interfere with the integration of top-down and bottom-up information flow. Studies in humans suggest more deficits in higher-order than in primary cortical areas in congenital deafness. That opens up the question how well neurons in higher-order areas can be activated by the input through the deprived auditory pathway after restoration of hearing with cochlear implants. Further it is unclear whether their interconnections to lower order areas are impaired by absence of hearing. Corticocortical anatomical fiber tracts and general auditory responsiveness in both primary and higher-order areas are generally preserved in absence of auditory experience. However, the existing data suggest a dichotomy between preservation of anatomical cortical connectivity in congenital deafness and functional deficits in corticocortical coupling. Further, cross-modal reorganization observed in congenital deafness in specific cortical areas appears to be established by functional synaptic changes and rests on anatomically preserved, genetically-predetermined and molecularly patterned circuitry connecting the sensory systems. Current data indicate a reduced corticocortical functional coupling between cortical auditory areas in congenital deafness, both in bottom-up and top-down information stream. Consequently, congenital deafness is likely to result in a deficit in predictive coding that affects learning ability after late cochlear implantation.
Topics: Acoustic Stimulation; Animals; Auditory Cortex; Auditory Pathways; Auditory Perception; Cortical Synchronization; Deafness; Evoked Potentials, Auditory; Hearing; Humans; Learning; Neuronal Plasticity
PubMed: 27637669
DOI: 10.1016/j.heares.2016.08.017 -
Molecular Therapy : the Journal of the... Sep 2023Hearing loss is a common disorder affecting nearly 20% of the world's population. Recently, studies have shown that inner ear gene therapy can improve auditory function...
Hearing loss is a common disorder affecting nearly 20% of the world's population. Recently, studies have shown that inner ear gene therapy can improve auditory function in several mouse models of hereditary hearing loss. In most of these studies, the underlying mutations affect only a small number of cell types of the inner ear (e.g., sensory hair cells). Here, we applied inner ear gene therapy to the Ildr1 (Ildr1) mouse, a model of human DFNB42, non-syndromic autosomal recessive hereditary hearing loss associated with ILDR1 variants. ILDR1 is an integral protein of the tricellular tight junction complex and is expressed by diverse inner ear cell types in the organ of Corti and the cochlear lateral wall. We simultaneously applied two synthetic adeno-associated viruses (AAVs) with different tropism to deliver Ildr1 cDNA to the Ildr1 mouse inner ear: one targeting the organ of Corti (AAV2.7m8) and the other targeting the cochlear lateral wall (AAV8BP2). We showed that combined AAV2.7m8/AAV8BP2 gene therapy improves cochlear structural integrity and auditory function in Ildr1 mice.
Topics: Humans; Animals; Mice; Receptors, Cell Surface; Deafness; Hearing Loss; Disease Models, Animal; Genetic Therapy
PubMed: 37481704
DOI: 10.1016/j.ymthe.2023.07.014 -
Lin Chuang Er Bi Yan Hou Tou Jing Wai... Apr 2021Aminoglycoside antibiotics can cause irreversible hearing loss, but they are still widely used because of their low production cost and broad-spectrum effect on most... (Review)
Review
Aminoglycoside antibiotics can cause irreversible hearing loss, but they are still widely used because of their low production cost and broad-spectrum effect on most infections. Although it has been studied for decades, the mechanism of aminoglycoside-induced deafness has not been fully elucidated. Since patients'individual susceptibility to aminoglycoside-ototoxicity varies considerably, it is necessary to identify high-risk patients. This review summarizes the genetic mutations linked to aminoglycoside-induced deafness, in order to provide reference for further prevention and treatment of aminoglycoside-induced deafness.
Topics: Aminoglycosides; Anti-Bacterial Agents; Deafness; Genetic Predisposition to Disease; Hearing Loss, Sensorineural; Humans; RNA, Ribosomal
PubMed: 33794642
DOI: 10.13201/j.issn.2096-7993.2021.04.021 -
International Journal of Pediatric... Oct 2022Cochlear implants (CIs) are a successful alternative in cases with severe-to-profound HL. In these individuals, visual cross-modal re-organization can occur because of...
UNLABELLED
Cochlear implants (CIs) are a successful alternative in cases with severe-to-profound HL. In these individuals, visual cross-modal re-organization can occur because of hearing loss where the visual cortex will recruit auditory cortical areas for visual processing.
OBJECTIVES
This work is designed to study visual evoked potentials (VEPs) in children fitted with CIs in comparison to normal hearing children.
METHOD
This work included 2 groups of children: Group I included 20 normal hearing children and study group included 25 children fitted with unilateral CIs. All cases were subjected to Thorough otological history. Check up on CIs performance using physical check and Aided sound field examination, ophthalmic examination and Pattern Visual Evoked Potentials (pVEPs).
RESULTS
Both groups showed no significant difference as regard age or sex. And both had normal ophthalmic examinations. Children of the study groups showed satisfactory aided response. As regard pVEPs, the study group showed significant higher P100 amplitude in comparison to the control group.
CONCLUSION
This study showed that deafness could induced cortical organization in the visual cortex and not limited to the auditory cortex only.
Topics: Auditory Cortex; Child; Cochlear Implantation; Cochlear Implants; Deafness; Ear Diseases; Evoked Potentials, Auditory; Evoked Potentials, Visual; Humans
PubMed: 35930866
DOI: 10.1016/j.ijporl.2022.111250