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JPMA. the Journal of the Pakistan... Sep 2021Evoked Potentials are electrical potentials that occur in a group of neurons in response to stimulation of a sensory organ which can be recorded by surface electrodes.... (Review)
Review
Evoked Potentials are electrical potentials that occur in a group of neurons in response to stimulation of a sensory organ which can be recorded by surface electrodes. Testing evoked potentials is useful in assessing the integrity of neuronal pathways both at sensory and motor levels of neural control. Early auditory evoked potentials include cochlear and brainstem auditory-evoked potentials, popularly known as electrocochleogram, and auditory brainstem response. Evoked potential audiometry is a neurophysiogical test to assess auditory pathway function in response to auditory stimuli. Auditory brainstem response mainly assesses brainstem functions and integrity. These evoked potentials are widely used for assessment of the cochlear functions, auditory nerve and the brainstem. Most common indications for auditory evoked potentials include routine newborn hearing screening for auditory pathway deficits, detecting retrocochlear pathologies, intraoperative and intensive care monitoring, frequency-related measurement of auditory sensitivity and for diagnosing some demyelinating disorders in initial stages. The current narrative review was planned to highlight auditory brainstem response recording's basic principles, uses and methods of interpretation in health and disease phases.
Topics: Brain Stem; Cochlea; Cochlear Nerve; Evoked Potentials, Auditory, Brain Stem
PubMed: 34580520
DOI: 10.47391/JPMA.03-432 -
Hearing Research Sep 2019This paper presents evidence for a strong connection between the development of speech and language skills and musical activities of children and adolescents with... (Review)
Review
This paper presents evidence for a strong connection between the development of speech and language skills and musical activities of children and adolescents with hearing impairment and/or cochlear implants. This conclusion is partially based on findings for typically hearing children and adolescents, showing better speech and language skills in children and adolescents with musical training, and importantly, showing increases of speech and language skills in children and adolescents taking part in musical training. Further, studies of hearing-impaired children show connections between musical skills, involvement in musical hobbies, and speech and language skills. Even though the field is still lacking large-scale randomised controlled trials on the effects of musical interventions on the speech and language skills of children and adolescents with hearing impairments and cochlear implants, the current evidence seems enough to urge speech therapists, music therapists, music teachers, parents, and children and adolescents with hearing impairments and/or cochlear implants to start using music for enhancing speech and language skills. For this reason, we give our recommendations on how to use music for language skill enhancement in this group.
Topics: Adolescent; Adolescent Development; Age Factors; Auditory Pathways; Auditory Perception; Child; Child Language; Child, Preschool; Cochlear Implantation; Cochlear Implants; Combined Modality Therapy; Hearing; Hearing Disorders; Humans; Music Therapy; Persons With Hearing Impairments; Recovery of Function; Speech; Treatment Outcome
PubMed: 31265971
DOI: 10.1016/j.heares.2019.06.003 -
Philosophical Transactions of the Royal... Jan 2020Humans and songbirds learn to sing or speak by listening to acoustic models, forming auditory templates, and then learning to produce vocalizations that match the... (Review)
Review
Humans and songbirds learn to sing or speak by listening to acoustic models, forming auditory templates, and then learning to produce vocalizations that match the templates. These taxa have evolved specialized telencephalic pathways to accomplish this complex form of vocal learning, which has been reported for very few other taxa. By contrast, the acoustic structure of most animal vocalizations is produced by species-specific vocal motor programmes in the brainstem that do not require auditory feedback. However, many mammals and birds can learn to fine-tune the acoustic features of inherited vocal motor patterns based upon listening to conspecifics or noise. These limited forms of vocal learning range from rapid alteration based on real-time auditory feedback to long-term changes of vocal repertoire and they may involve different mechanisms than complex vocal learning. Limited vocal learning can involve the brainstem, mid-brain and/or telencephalic networks. Understanding complex vocal learning, which underpins human speech, requires careful analysis of which species are capable of which forms of vocal learning. Selecting multiple animal models for comparing the neural pathways that generate these different forms of learning will provide a richer view of the evolution of complex vocal learning and the neural mechanisms that make it possible. This article is part of the theme issue 'What can animal communication teach us about human language?'
Topics: Animals; Auditory Pathways; Auditory Perception; Birds; Brain; Chiroptera; Feedback, Sensory; Humans; Learning; Neural Pathways; Songbirds; Speech; Vocalization, Animal
PubMed: 31735157
DOI: 10.1098/rstb.2018.0406 -
International Journal of Molecular... Mar 2021Growth hormone (GH) plays an important role in auditory development during the embryonic stage. Exogenous agents such as sound, noise, drugs or trauma, can induce the... (Review)
Review
Growth hormone (GH) plays an important role in auditory development during the embryonic stage. Exogenous agents such as sound, noise, drugs or trauma, can induce the release of this hormone to perform a protective function and stimulate other mediators that protect the auditory pathway. In addition, GH deficiency conditions hearing loss or central auditory processing disorders. There are promising animal studies that reflect a possible regenerative role when exogenous GH is used in hearing impairments, demonstrated in in vivo and in vitro studies, and also, even a few studies show beneficial effects in humans presented and substantiated in the main text, although they should not exaggerate the main conclusions.
Topics: Animals; Auditory Cortex; Auditory Pathways; Cochlea; Cochlear Nerve; Gene Expression Regulation; Growth Hormone; Hearing Loss, Functional; Hearing Loss, Sensorineural; Hippocampus; Humans; Insulin-Like Growth Factor I; Nerve Regeneration; Noise
PubMed: 33799503
DOI: 10.3390/ijms22062829 -
Frontiers in Neuroscience 2022
PubMed: 35401079
DOI: 10.3389/fnins.2022.876798 -
Cold Spring Harbor Perspectives in... Aug 2019When hearing fails, cochlear implants (CIs) provide open speech perception to most of the currently half a million CI users. CIs bypass the defective sensory organ and... (Review)
Review
When hearing fails, cochlear implants (CIs) provide open speech perception to most of the currently half a million CI users. CIs bypass the defective sensory organ and stimulate the auditory nerve electrically. The major bottleneck of current CIs is the poor coding of spectral information, which results from wide current spread from each electrode contact. As light can be more conveniently confined, optical stimulation of the auditory nerve presents a promising perspective for a fundamental advance of CIs. Moreover, given the improved frequency resolution of optical excitation and its versatility for arbitrary stimulation patterns the approach also bears potential for auditory research. Here, we review the current state of the art focusing on the emerging concept of optogenetic stimulation of the auditory pathway. Developing optogenetic stimulation for auditory research and future CIs requires efforts toward viral gene transfer to the neurons, design and characterization of appropriate optogenetic actuators, as well as engineering of multichannel optical implants.
Topics: Animals; Auditory Pathways; Cochlear Implantation; Cochlear Implants; Deafness; Humans; Optogenetics; Prosthesis Design; Speech Perception
PubMed: 30323016
DOI: 10.1101/cshperspect.a033225 -
Neurobiology of Learning and Memory Mar 2022Increasing evidence has shown that noise overexposure could lead to impaired hippocampal function. Hippocampal alteration is also observed in several auditory deficits,... (Review)
Review
Increasing evidence has shown that noise overexposure could lead to impaired hippocampal function. Hippocampal alteration is also observed in several auditory deficits, including hearing loss, and tinnitus. Therefore, the functions of hearing and cognition interact with each other. Here, we summarize the evidence that noise affects the hippocampus from aspects of behavior, neurogenesis, ultrastructure, neurotransmission, other biomarkers, and electrophysiology. We also address hippocampal alterations in auditory disorders, including hearing loss and tinnitus. Based on the current state of the field, we point out several aspects that need further investigation. This review is not only to provide a comprehensive summary of the current state of the field but to emphasize that hearing matters in cognition and pave the way for future research.
Topics: Auditory Pathways; Hippocampus; Humans; Neurogenesis; Noise; Tinnitus
PubMed: 35124220
DOI: 10.1016/j.nlm.2022.107589