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
Vestibulo-ocular Reflex Physiology, Pathology And Rehabilitation
Funder
National Health and Medical Research Council
Summary
A sensation of movement from the inner ear is used to stabilise vision during head movements. Without it, every time you walk, run, or drive on a bumpy road, the world would appear to bounce. It can be debilitating when this sense doesn't work due to various diseases. This research examines how this sense works normally and the factors important for self-repair after injury. This work will also develop training exercises using a device for take-home balance rehabilitation.
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
A Balancing Act: A Three-pronged Approach To Vestibular Assessment
Funder
National Health and Medical Research Council
Funding Amount
$419,180.00
Summary
Vertigo and imbalance are common and disabling symptoms of vestibular (balance) dysfunction. This project will investigate three aspects of vestibular function: by searching for new balance reflexes, revealing the pattern of vestibular deficits in patients with a common form of vertigo caused by migraine, and exploring the impact of vestibular disease on thinking and memory. This research will improve our understanding of the vestibular system and facilitate the diagnosis of episodic vertigo.
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.
Our vestibular system provides us with the important sense of balance. When it fails we suffer debiltating bouts of vertigo and dizziness. A great deal is known about how balance signals are sent from the inner ear to our brains, but virtually nothing is known about the important signals the brain sends to the inner ear. In this study we will use a new perparation develped in our laboratory to examine how these essential brain signals control the function of our balance organs.
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 human brain has many subdivisions (�areas�) that are dedicated to vision, but in many cases their functions remain unclear. This project will study an area located deep in the brain, about which very little is known, and which appears to be affected from early stages in conditions such as Alzheimer�s disease. By understanding the patterns of electrical activity of cells in this region, and their connections with other brain areas, we hope to decipher their contribution to sensory cognition.
In the areas of the brain where visual information is processed, cells respond to the presentation of visual stimuli by changing their pattern of electrical activity. At the first level of analysis, the primary visual cortex (V1), individual cells become active only if line segments or borders of a particular orientation are present in their field of detection, which encompasses a small part of the visual scene. Cells in other visual cortical areas (the extrastriate cortex) perform more complex ....In the areas of the brain where visual information is processed, cells respond to the presentation of visual stimuli by changing their pattern of electrical activity. At the first level of analysis, the primary visual cortex (V1), individual cells become active only if line segments or borders of a particular orientation are present in their field of detection, which encompasses a small part of the visual scene. Cells in other visual cortical areas (the extrastriate cortex) perform more complex detection tasks in comparison with those in V1, which demand integration of information coming from much larger portions of the visual scene. One example of these more complex properties is the phenomenon of long-range contour integration, where our visual system groups individual line segments having similar orientations, so that they are perceived as part of the same contour. This property is reflected in the electrical responses of cells in the dorsomedial visual area (DM). How are properties such as orientation specificity and long-range contour integration created? To begin addressing this question, we will investigate correlations between the physiological properties of identified cells, the spatial distribution of their information collecting regions (dendrites), and the anatomical pathways by which they receive information from other parts of the brain. This is a basic science study aimed at determining the extent to which the anatomical structure of the brain helps define the function of individual cells and brain areas. Its primary benefit will be to increase our understanding of the mechanisms underlying all sensory processing in the brain. The knowledge obtained may also lead to developments in areas of applied research including medicine and cognitive science (for example, understanding how the brain learns to interpret visual information in early life, and how visual processing degrades with ageing).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.