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
A Molecular Approach To Constructing The Olfactory System
Funder
National Health and Medical Research Council
Funding Amount
$440,250.00
Summary
The olfactory (smell) system is a unique part of the nervous system; nerve cells are generated throughout life and it can regenerate even after injury. It therefore provides an excellent model for examining the growth, development and maintenance of nerve cells. This project will examine the effects on the organisation of the olfactory system when some guidance signals are altered. Information we obtain about how this system develops and regenerates may be useful in treating brain disorders and ....The olfactory (smell) system is a unique part of the nervous system; nerve cells are generated throughout life and it can regenerate even after injury. It therefore provides an excellent model for examining the growth, development and maintenance of nerve cells. This project will examine the effects on the organisation of the olfactory system when some guidance signals are altered. Information we obtain about how this system develops and regenerates may be useful in treating brain disorders and spinal injuries In the current project we will examine the effects of specific nerve cell guidance molecules by generating transgenic mice that produce these molecules only in the olfactory system. We can then determine what changes occur to the nerve cells when these extra molecules are produced. The results of these experiments will provide important information on the the initial growth and targeting of these nerve cells which may have implications for regeneration of these as well as other nerve cells.Read moreRead less
Defining The Role Of EphA5 In Olfactory Axon Growth, Guidance And Fasciculation
Funder
National Health and Medical Research Council
Funding Amount
$256,320.00
Summary
The olfactory (smell) system is a unique part of the nervous system; nerve cells are generated throughout life and it can regenerate even after injury. It therefore provides an excellent model for examining the growth, development and maintenance of nerve cells. This project will examine the effects on the organisation of the olfactory system when some guidance signals are altered. Information we obtain about how this system develops and regenerates may be useful in treating brain disorders and ....The olfactory (smell) system is a unique part of the nervous system; nerve cells are generated throughout life and it can regenerate even after injury. It therefore provides an excellent model for examining the growth, development and maintenance of nerve cells. This project will examine the effects on the organisation of the olfactory system when some guidance signals are altered. Information we obtain about how this system develops and regenerates may be useful in treating brain disorders and spinal injuries In the current project we will examine the effects of specific nerve cell guidance molecules by generating transgenic mice that produce these molecules only in the olfactory system. We can then determine what changes occur to the nerve cells when these extra molecules are produced. In addition, we will also examine the behaviour of live cells as they are growing. In the past all attempts to understand how nerve cell connections are formed in the olfactory system have used dead tissue that has been permanently preserved. In this project we have the unique opportunity to visualise living nerve cells to enable us to determine how the cells react to the guidance signals. The advantage of this approach is that it allows us to identify important interactions as they occur, rather than attempting to decipher them after they have occurred. An analogy would be watching a football game live and observing how goals were scored and appreciating the performance of individual players versus trying to guess from the final score how the game was played and who the key performers were. The results of these experiments will provide important information on the regeneration of olfactory nerve cells, as well as on the initial growth and targeting of these nerve cells.Read moreRead less
Olfactory Ensheathing Cells: A Major Contributor To Axon Guidance?
Funder
National Health and Medical Research Council
Funding Amount
$575,749.00
Summary
The olfactory (smell) system is a unique part of the nervous system because nerve cells are generated throughout life. Understanding how the olfactory system grows and regenerates may lead to therapeutic approaches to repair other regions of the nervous system. This project will use high resolution digital time-lapse imaging of living nerve cells and the specialised cells called olfactory ensheathing cells to determine how the behaviour of these cells can be manipulated to improve regeneration.