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.
Physiological significance of transient receptor potential (TRPC3) ion channels in the cochlea. The project seeks to discover the function of transient receptor potential (TRPC3) ion channels in the cochlea. Recent studies have suggested that these proteins, which are expressed by the sensory and neural cells, are key elements regulating sound transduction and neurotransmission. The new knowledge about the physiological processes underlying hearing that this work will provide, will significantl ....Physiological significance of transient receptor potential (TRPC3) ion channels in the cochlea. The project seeks to discover the function of transient receptor potential (TRPC3) ion channels in the cochlea. Recent studies have suggested that these proteins, which are expressed by the sensory and neural cells, are key elements regulating sound transduction and neurotransmission. The new knowledge about the physiological processes underlying hearing that this work will provide, will significantly benefit national and international translational research that seeks to develop systems for controlling the sensitivity of our senses, developing biosensors, interacting with neural networks and developing neural prostheses. International collaborators in this project have enabled development of new models, technology and research training opportunities.Read moreRead less
Suction pipette measurements of mammalian rod photoreceptor recovery following intense bleaching exposures. The aim of this project is to discover the events and processes that prevent retinal photoreceptors from recovering instantaneously following the cessation of exposure to extremely bright illumination. Recordings will be made from single rod photoreceptors cells isolated from the mammalian retina. The work will uncover the relative roles of the 'photoproducts' created when rhodopsin abso ....Suction pipette measurements of mammalian rod photoreceptor recovery following intense bleaching exposures. The aim of this project is to discover the events and processes that prevent retinal photoreceptors from recovering instantaneously following the cessation of exposure to extremely bright illumination. Recordings will be made from single rod photoreceptors cells isolated from the mammalian retina. The work will uncover the relative roles of the 'photoproducts' created when rhodopsin absorbs light: e.g. intermediates such as metarhodopsin and opsin. The molecular knowledge obtained will help us to understand why it is that the visual system recovers so slowly after the eye has experienced very intense light.Read moreRead less
The effect of multisensory and sensory-motor training on auditory accommodation. Learning to use a hearing aid or cochlear implant requires the brain to make adaptive changes to the new type of sensory information provided to the ears. This project examines what drives this accommodation and how we may accelerate the process and maximise its benefits by training so that listeners are able to make better use of these devices.
The first stage of vision: transduction and adaptation in retinal photoreceptors. The project aims to provide a detailed understanding of the molecular steps involved in the first stage of vision - the conversion of light into a neural signal in the rod and cone photoreceptors of the retina. The significance of this is that it will explain the initial events that enable us to see, and will help explain the deficits that occur when the process fails. The outcome will be a comprehensive understand ....The first stage of vision: transduction and adaptation in retinal photoreceptors. The project aims to provide a detailed understanding of the molecular steps involved in the first stage of vision - the conversion of light into a neural signal in the rod and cone photoreceptors of the retina. The significance of this is that it will explain the initial events that enable us to see, and will help explain the deficits that occur when the process fails. The outcome will be a comprehensive understanding of how our photoreceptors respond with extreme sensitivity, yet great rapidity, and over an enormous range of light intensities, thus endowing us with our remarkable sense of vision.Read moreRead less
A contractile cochlear frame - a possible new mechanism of sound adaptation. It is generally accepted that the rigid frame that harbours sensory structures in the hearing organs of modern higher vertebrates has only a passive supporting role. We have discovered a contractile component in the cartilaginous cochlear frame of the lizard Teratoscincus scincus and demonstrated that the tonus of the contractile tissue can be regulated. We hypothesize a new, previously unknown mechanism of slow mechani ....A contractile cochlear frame - a possible new mechanism of sound adaptation. It is generally accepted that the rigid frame that harbours sensory structures in the hearing organs of modern higher vertebrates has only a passive supporting role. We have discovered a contractile component in the cartilaginous cochlear frame of the lizard Teratoscincus scincus and demonstrated that the tonus of the contractile tissue can be regulated. We hypothesize a new, previously unknown mechanism of slow mechanical adaptation in the vertebrate hearing organ. The aim of the proposed project is to examine this hypothesis in more detail.
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Functional imaging of colour pathways in the living eye. In order to repair or regenerate a diseased eye, we require knowledge of the normal pattern or nerve cell connections, and knowing how biology solves the problem of colour vision can be used to improve the design of artificial vision systems. The adaptive optics machine we will build in this project can be used to image nerve cells, fine blood vessels, and nerve fibre bundles in the normal and diseased eye. This will improve Australia's re ....Functional imaging of colour pathways in the living eye. In order to repair or regenerate a diseased eye, we require knowledge of the normal pattern or nerve cell connections, and knowing how biology solves the problem of colour vision can be used to improve the design of artificial vision systems. The adaptive optics machine we will build in this project can be used to image nerve cells, fine blood vessels, and nerve fibre bundles in the normal and diseased eye. This will improve Australia's research and development capacity in this new area of medical diagnostics. Our machine will be made available to other Australian laboratories and will improve the national capacity for making further scientific discoveries about how the visual system works.Read moreRead less
Organization Of Descending Auditory Projections From Inferior Colliculus To Cochlear Nucleus
Funder
National Health and Medical Research Council
Funding Amount
$473,121.00
Summary
Sensory information gains awareness by ascending brain pathways to reach consciousness. Descending projections, however, have grown in importance because of implications for feedback management of ascending signals. Studies of these pathways will provide insight into auditory processing with respect to selective volume control, calibration adjustments between the two ears, and the extraction of signals from background noise. The data could lead to new strategies for treating hearing disorders.
Centre-surround interactions in ageing human vision. Australia has a rapidly ageing population. This project will study how ageing affects the visual perception of objects presented on non-uniform backgrounds. Our ability to discriminate objects from their backgrounds is key to most natural visual tasks. The visual processes involved are known as centre-surround interactions, and are considered fundamental building blocks to human perception. This project will significantly advance our knowledge ....Centre-surround interactions in ageing human vision. Australia has a rapidly ageing population. This project will study how ageing affects the visual perception of objects presented on non-uniform backgrounds. Our ability to discriminate objects from their backgrounds is key to most natural visual tasks. The visual processes involved are known as centre-surround interactions, and are considered fundamental building blocks to human perception. This project will significantly advance our knowledge of which spatial visual mechanisms are altered due to age, supplying key information for understanding and improving visual environments for the elderly, as well as increasing knowledge of the brain mechanisms susceptible to the ageing process.Read moreRead less
Listen and learn - statistical learning and the adapting auditory brain. This project aims to explore the link between rapid neural adaptation - a form of learning referred to as statistical learning - and human listening performance in noisy environments. The project aims to generate a new understanding of mechanisms that contribute to listeners' abilities to understand speech in noise, and to complex communication disorders such as dyslexia. Expected outcomes will include increased capacity to ....Listen and learn - statistical learning and the adapting auditory brain. This project aims to explore the link between rapid neural adaptation - a form of learning referred to as statistical learning - and human listening performance in noisy environments. The project aims to generate a new understanding of mechanisms that contribute to listeners' abilities to understand speech in noise, and to complex communication disorders such as dyslexia. Expected outcomes will include increased capacity to investigate a broad range of cognitive and communication functions. Benefits will include potential technologies and algorithms to assist listening (in devices such as hearing aids), language development and reading.Read moreRead less