Mechanisms Of Body Representation And The Sensory Consequences Of Stroke
Funder
National Health and Medical Research Council
Funding Amount
$408,842.00
Summary
How does the brain control movement without vision? We cannot see our mouth but can easily put food in it. The brain uses a combination of sensory signals and stored models of the body, to control movement. The body models, and their interaction with sensory information, is not well understood. but they are disrupted by common clinical disorders. This research project investigates unsolved questions about the body model including how it is affected by stroke.
Neuronal Activity And Variability Underlying Perception And Action
Funder
National Health and Medical Research Council
Funding Amount
$349,802.00
Summary
Perception and behaviour are often unpredictable. We do not identically perceive repeated stimuli, and even professional athletes cannot precisely replicate their actions. This project compares variations in the activity of motion-sensitive neurons in the brain with variability in motion perception and eye movements. This should give insights into how neuronal activity underlies conscious perception and eye movements and may ultimately help treat conditions with impaired control of movement.
Understanding The Organisation Of The Medial Parietal Cortex: Sensorimotor Integration For Goal-directed Behaviour
Funder
National Health and Medical Research Council
Funding Amount
$551,862.00
Summary
Reaching and grasping are of obvious significance for a productive life, and many of the brain areas known to be involved in the direction of arm movements are located in the parietal lobe. Stroke affecting this part of the brain causes disability, as people become unable to reach accurately, or to close their hands around objects with appropriate strength. This project will combine modern physiological and anatomical methods to reveal the brain circuitry responsible for such crucial skills.
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
The roles of spectral cues and auditory plasticity in auditory localisation, speech segregation and speech intelligibility. Our recent work shows that high frequency energy in speech is important for the localisation of speech and may also aid in improving speech intelligibility in noisy environments. The work proposed here will systematically explore this somewhat surprising new finding and the results will be incorporated into a predictive model of speech intelligibility under spatial listenin ....The roles of spectral cues and auditory plasticity in auditory localisation, speech segregation and speech intelligibility. Our recent work shows that high frequency energy in speech is important for the localisation of speech and may also aid in improving speech intelligibility in noisy environments. The work proposed here will systematically explore this somewhat surprising new finding and the results will be incorporated into a predictive model of speech intelligibility under spatial listening conditions. This work includes a systematic study of auditory functional plasticity to changes in the spatial cues. Taken together, the outcomes of this work will unlock a range of new approaches to enhancing spatial hearing in multi-channel communication devices and spatial hearing aids.Read moreRead less
Acoustic, spatial and informational cues used to solve the cocktail party problem. Speech is the principal mode of human communication and yet we understand little about how we are able to concentrate on one talker against a noisy background. Significant improvements in supporting listening by the hearing impaired, in teleconferencing systems and computer speech interfaces are dependent on a more advanced understanding of how we solve this cocktail party problem. This research explores the acous ....Acoustic, spatial and informational cues used to solve the cocktail party problem. Speech is the principal mode of human communication and yet we understand little about how we are able to concentrate on one talker against a noisy background. Significant improvements in supporting listening by the hearing impaired, in teleconferencing systems and computer speech interfaces are dependent on a more advanced understanding of how we solve this cocktail party problem. This research explores the acoustic, spatial and informational cues used by the healthy auditory system to achieve this remarkable feat of signal processing. There is significant potential for commercialization of the IP that will arise from this research.Read moreRead less
This is a study of the senses which arise from our muscles and which tell us where our different body parts are, at any point in time. These senses, collectively called proprioception, are also involved in the automatic, unconscious control of our muscles. So, ultimately, they allow us to stand and to move freely with precision and confidence, even in the dark. One of these senses, the sense of effort or of heaviness, is believed to be generated within the brain. It intensifies when we become fa ....This is a study of the senses which arise from our muscles and which tell us where our different body parts are, at any point in time. These senses, collectively called proprioception, are also involved in the automatic, unconscious control of our muscles. So, ultimately, they allow us to stand and to move freely with precision and confidence, even in the dark. One of these senses, the sense of effort or of heaviness, is believed to be generated within the brain. It intensifies when we become fatigued. These experiments will be concerned with finding out more about how this works. We have a method that uses magnetic stimulation of the brain to change its control of our muscles. Using it we will learn how this sense is generated. When we close our eyes and move our limbs we realise that we know exactly where they are at any point in time. It remains uncertain exactly how this information is generated within the nervous system. One idea, arising from some recent experiments which we want to test, is that as we move the limb, the skin over the moving parts is stretched and stretch-sensitive nerve endings in the skin provide us with information about the movement. Alternatively, perhaps it is the effort we exert to maintain limb position against the force of gravity which tells us where the limb is. In another recent study we have found that when a muscle has become painful from excessive exercise or from some local strain injury, our ability to control the muscle and so move the limb is no longer as effective. We want to study the underlying nervous mechanisms responsible for the changes in movement control. Are they designed to spare the muscle while it recovers from injury? How are they brought about? All of this work is important for a better understanding of ourselves, for a better clinical diagnosis when something goes wrong and for improved treatment of diseased or injured muscles.Read moreRead less
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.