Improving Music Appreciation For People With Prosthetic Hearing Devices By Enhancing Auditory Stream Segregation
Funder
National Health and Medical Research Council
Funding Amount
$266,560.00
Summary
Music perception is one of the most often-cited problems for people with hearing aids or cochlear implants. Part of the problem is related to the reduced ability to hear different instruments or melodic lines separately. This ability is based on perceptual differences between auditory streams. Psychophysics experiments will be performed to understand the effect of different acoustic parameters on auditory streaming. An innovative approach to restore music appreciation will be tested on people wi ....Music perception is one of the most often-cited problems for people with hearing aids or cochlear implants. Part of the problem is related to the reduced ability to hear different instruments or melodic lines separately. This ability is based on perceptual differences between auditory streams. Psychophysics experiments will be performed to understand the effect of different acoustic parameters on auditory streaming. An innovative approach to restore music appreciation will be tested on people with impaired hearing.Read moreRead less
Cochlear Type II Neurons In Contralateral Suppression
Funder
National Health and Medical Research Council
Funding Amount
$459,434.00
Summary
Sound in one ear affects hearing in the other ear. This contralateral suppression is important for hearing attention and protection from noise damage. We will test the hypothesis that cochlear type II sensory neurons provide the sensory input for this process using models where neuronal development is altered, or the neurons are removed. The study addresses hearing disability in society, facilitating cochlear prosthesis development and the understanding of hearing loss.
Early Indicators Of Noise Injury: Are Decreased Auditory Processing Skills Evident In Noise-exposed Adults Prior To Diagnosis Of Hearing Loss?
Funder
National Health and Medical Research Council
Funding Amount
$367,605.00
Summary
Recent research indicates that noise-exposed individuals with similar hearing thresholds to non-noise exposed counterparts are more likely to have diminished temporal and spectral auditory processing abilities. This research aims to determine the relationship between noise exposure levels and auditory processing difficulties; the influence of musical training in ameliorating these difficulties; and a neurological model of causation, operation and possible remediation of these difficulties.
The research will investigate the mechanisms by which our brains are able to listen selectively to sounds of interest in competing background noise. This will be investigated in normal hearing subjects, those with partial deafness and in profoundly deaf patients who use a cochlear implant. If deaf patients can learn to use cues to enhance detection of sounds of interest this could have an impact on the effectiveness of hearing aids and cochlear implants in noisy listening situations
NEURAL MODULATION OF HEARING LOSSES INDUCED BY LOUD SOUND
Funder
National Health and Medical Research Council
Funding Amount
$290,500.00
Summary
Loud sounds, from occupational and recreational sources, are the most common threat to hearing and can result in temporary hearing losses (as might be experienced after an evening at a noisy pub or concert) or permanent hearing losses (after prolonged or multiple loud sounds, as for example in a noisy work environment). Noise reduction programs are either not always possible or effectively applied. A parallel strategy is the study of biological mechanisms that may ameliorate hearing damage, with ....Loud sounds, from occupational and recreational sources, are the most common threat to hearing and can result in temporary hearing losses (as might be experienced after an evening at a noisy pub or concert) or permanent hearing losses (after prolonged or multiple loud sounds, as for example in a noisy work environment). Noise reduction programs are either not always possible or effectively applied. A parallel strategy is the study of biological mechanisms that may ameliorate hearing damage, with a view to optimising such mechanisms. I propose to build on seminal Australian work to examine how one such system, nerves from the brain to the inner ear (the site of most damage from loud sounds), modulates hearing losses caused by loud sounds. Early studies indicated these nerves could protect from damage induced by short-lasting loud sound and this has led to international interest in functional applications of such protection to reduce hearing damage suffered by humans. However, my recent work indicates the nerves exert complex protective and exacerbative effects to loud sounds similar to common trauma or occurring under conditions similar to common trauma. They even exacerbate hearing losses due to loud sound, especially when there is an imbalance in hearing sensitivity in the two ears (bilateral) similar to what is common in humans. These findings make it critical that functional application be delayed until the full range of effects exerted by the nerves is understood. I propose to elucidate the novel complex effects of these nerves to loud sound. Specific aims are: (1) To understand effects of these pathways to loud sounds like those encountered by humans, (2) To investigate how chronic imbalanced bilateral hearing sensitivity, like that common in humans, alters effects of the nerves and when they change from being protective to exacerbative, (3) To adduce how an atraumatic sound affects hearing losses due to later loud sound and the role played by these nerves.Read moreRead less
Efferent Control Circuitry Of The Auditory Brainstem
Funder
National Health and Medical Research Council
Funding Amount
$406,306.00
Summary
Detection of important sounds within a noisy background is a crucial function of the mammalian hearing system and defects in this function impair social interaction, learning and development. In addition, activity in the brain needs to be carefully regulated by intrinsic circuitry in order to prevent excessive activity responsible for conditions such as tinnitus. The mechanisms by which the brain achieves this are poorly understood and this project aims to improve our understanding of some of th ....Detection of important sounds within a noisy background is a crucial function of the mammalian hearing system and defects in this function impair social interaction, learning and development. In addition, activity in the brain needs to be carefully regulated by intrinsic circuitry in order to prevent excessive activity responsible for conditions such as tinnitus. The mechanisms by which the brain achieves this are poorly understood and this project aims to improve our understanding of some of the brain circuits involved.Read moreRead less
The Role Of Mitochondrial DNA In Age-related Hearing Loss
Funder
National Health and Medical Research Council
Funding Amount
$260,475.00
Summary
Hearing loss is an extremely common and under-studied age-related disability, affecting 39% of Australians aged 50 years or older. Both genetic and environmental factors may contribute to the development of age-related hearing loss. Human genetic material (DNA) resides in two places in body cells; the nucleus and in organelles called mitochondria. This is due to the fact that mitochondria were derived from bacteria that were engulfed by the cell back in primordial life. Although this genetic mat ....Hearing loss is an extremely common and under-studied age-related disability, affecting 39% of Australians aged 50 years or older. Both genetic and environmental factors may contribute to the development of age-related hearing loss. Human genetic material (DNA) resides in two places in body cells; the nucleus and in organelles called mitochondria. This is due to the fact that mitochondria were derived from bacteria that were engulfed by the cell back in primordial life. Although this genetic material is different to nuclear DNA, it has an essential role in helping to provide energy for the cell. Genetic mutations in the DNA residing in the mitochondria have been associated with a number of conditions, usually affecting tissues that require large amounts of energy, such as the brain, muscle, heart, retina and the cochlea of the ear. The commonest clinical manifestation of mitochondrial disease is thought to be hearing loss. This project investigates the role that abnormal mitochondrial DNA plays in the development of hearing impairment by studying subjects from a representative Australian community who participated in a large population study of hearing loss. We will assess whether different sectors of mitochondrial DNA predispose particular individuals to the development of hearing loss or accelerate its onset. The Blue Mountains Hearing Study is able to take into account other factors known to be associated with hearing loss (industrial noise exposure, diabetes, smoking).Read moreRead less
Signals And Noise: A Study Of The Neurocognitive Mechanisms Underpinning Habituation To Noise In Normal And Damaged Hearing
Funder
National Health and Medical Research Council
Funding Amount
$408,938.00
Summary
McLachlan and Wilson recently published the first model of hearing that combines brain structure with function. This model postulates that recognition mechanisms initiate first, and then regulate the processing of other features. This project will investigate whether recognition mechanisms enable the auditory system to adapt to repetitive (background) noise by predicting and inhibiting responses to these sounds, and any changes in these mechanisms that may accompany hearing damage and tinnitus.
Hearing Protection Conferred By P2X2 Receptor Signaling In The Cochlea
Funder
National Health and Medical Research Council
Funding Amount
$580,019.00
Summary
Hearing loss from noise damage and ageing is the principal sensory disability in our society. This project will determine the contribution of the P2X2 receptor to protection from noise-induced hearing loss. We have found that P2X2 knockout mice have minimal temporary threshold shift. We will investigate the physiological basis for this and determine why this mouse model has greater hearing loss with intense sound and faster age-related hearing loss compared with wildtype controls.