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.
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
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
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.
In the normal process of hearing, the brain actively selects sounds of interest from competing background sounds. This normal auditory function is indispensible for children and adults to cope in non-optimal listening environments, however the mechanisms by which such performance is achieved are poorly understood. This project will investigate the nerve circuits that enable this to occur and will also investigate how these circuits malfunction in various types of partial deafness. The results wi ....In the normal process of hearing, the brain actively selects sounds of interest from competing background sounds. This normal auditory function is indispensible for children and adults to cope in non-optimal listening environments, however the mechanisms by which such performance is achieved are poorly understood. This project will investigate the nerve circuits that enable this to occur and will also investigate how these circuits malfunction in various types of partial deafness. The results will improve our understanding of how we detect sounds and the impact of hearing pathologies on this process.Read moreRead less
Opening Windows To The Listening Brain: Developing Objective Measures Of Hearing Acuity In The Human Brain.
Funder
National Health and Medical Research Council
Funding Amount
$319,329.00
Summary
Up to 160,000 Australians are un-employed due to hearing impairment, costing an estimated $12 billion per year. I will undertake systematic research which will result in EEG-based clinical tools designed to measure the reliability and acuity with which brainstem and brain structures are able to encode fine details in sounds. These tools will improve diagnostic and prognostic tests, especially for clinicians and parents of infants diagnosed with auditory neuropathies.
Studies Of The Effects Of Asymmetric Hearing Loss On The Brain
Funder
National Health and Medical Research Council
Funding Amount
$920,076.00
Summary
Hearing loss impairs the normal development and maintenance of auditory pathways. Irreversible pathologies persist when hearing is not restored in a timely manner. While cochlear implantation is the accepted treatment for profound sensorineural hearing loss, there is significant variability in outcomes. Some of this variability is linked to the degree of hearing asymmetry. Thus, we propose to study brain changes in the auditory system that accompany asymmetric hearing impairment.
Nanoparticle Based Neurotrophin Delivery To Promote Directed Neurite Growth And Auditory Nerve Rescue Following Deafness
Funder
National Health and Medical Research Council
Funding Amount
$506,724.00
Summary
The cochlear implant provides hearing information to the severe-profoundly deaf by electrically stimulating the auditory nerves of the inner ear. Deafness causes these auditory nerves to gradually degenerate leaving fewer nerves for the cochlear implant to stimulate. We propose to reverse this neural degeneration by delivering therapeutic drugs to the inner ear using tiny nanoparticles. This novel technology is expected to have application in other areas of neural degenerative disease.
Intrinsic Hearing Protection Mechanisms: A Pathway To Prevention Of Noise-induced Hearing Loss
Funder
National Health and Medical Research Council
Funding Amount
$625,900.00
Summary
Noise-induced hearing loss (NIHL) is a significant contributor to the total burden of disease. We recently determined that when the ear is exposed to sustained noise, the cochlea is protected from damage by activation of a specific (P2X2) receptor, evident as reversible hearing adaptation. This study will determine the downstream signalling from this receptor. This will support assessment of vulnerability to NIHL and contribute to development of hearing therapeutics.