Cortical Excitation In Migraine: Using Vision To Understand And Track Brain Excitability
Funder
National Health and Medical Research Council
Funding Amount
$521,628.00
Summary
Migraine is a common neurological condition affecting approximately 15% of adults. Therapies are most effective if used early, yet many people are unable to predict their migraines or to recognize early signs. In addition to headache, key symptoms include abnormal visual and auditory experience. We propose that aspects of vision and hearing will vary systematically according to the current brain status. Our translational goal is to develop tests that allow individuals to better manage migraine.
Much of the human brain is devoted to vision, which requires the integrated activity of many interconnected areas of the cerebral cortex. Damage to these areas is a relatively common complication of preterm delivery and- or perinatal conditions including trauma and infection. The severity of both the short- and long-term effects of these lesions appears to be related to the time of the damage. The aim of this project is to investigate the way in which the multiple visual areas of the brain devel ....Much of the human brain is devoted to vision, which requires the integrated activity of many interconnected areas of the cerebral cortex. Damage to these areas is a relatively common complication of preterm delivery and- or perinatal conditions including trauma and infection. The severity of both the short- and long-term effects of these lesions appears to be related to the time of the damage. The aim of this project is to investigate the way in which the multiple visual areas of the brain develop and become 'wired' together in the period following birth. We will also determine if there are mechanisms which allow alternate routes to be found for processing visual information while the brain is still establishing connections between its multiple areas. This will allow us to understand the anatomical and physiological bases of the deficits caused by early damage to the visual areas of the brain, and perhaps point to strategies that will lead to improved recovery of visual function.Read moreRead less
The Plastic Effects Of Long-term Partial Deafness And Chronic Cochlear Implant Use On The Response Of Primary Auditory Cortex To Combined Electro-acoustic Stimulation
Funder
National Health and Medical Research Council
Funding Amount
$560,267.00
Summary
Cochlear implants were originally used only in cases of profound deafness, but are now being used in patients who have some residual hearing at low frequencies. Our goal is to better understand how the electrical information from the cochlear implant and the acoustic information provided by the residual hearing are combined in the brain to produce unified perception of the auditory environment.
InTOUCH: Tactile Assessment In Children With Cerebral Palsy
Funder
National Health and Medical Research Council
Funding Amount
$176,571.00
Summary
Recent research finds that over 70% of children with unilateral cerebral palsy have impairments in touch function that affect how well they can use their hands. Until now, the severity and extent of this deficit has been unknown, and so children with cerebral palsy have not been receiving touch assessments. This project aims to increase awareness of touch impairments and achieve integration of touch assessment into routine examaination.
The broad aim of this project is to understand how the eye receives visual signals and sends them to the brain. Our experimental goal is to study the structure of neural connections in a poorly understood division of the visual system, called the koniocellular pathway. The cells of the koniocellular pathway make up close to 10 percent of all projections from the eye to the brain, but their functions are almost completely unknown. The fovea is a specialised region of the retina (the nerve cells w ....The broad aim of this project is to understand how the eye receives visual signals and sends them to the brain. Our experimental goal is to study the structure of neural connections in a poorly understood division of the visual system, called the koniocellular pathway. The cells of the koniocellular pathway make up close to 10 percent of all projections from the eye to the brain, but their functions are almost completely unknown. The fovea is a specialised region of the retina (the nerve cells which line the back of the eye). It is characterised by a very high density of cone photoreceptors, and is essential for high-acuity vision. This makes the fovea the most important part of the primate retina, but the high density of nerve cells there is thought to be the reason why the fovea is especially vulnerable to disease and age-related degeneration. Our aim is to analyse, using high-resolution microscopic techniques, the connections of koniocellular-pathway cells within the retina. We specifically aim to discover whether the koniocellular pathway contributes to foveal vision. Recent work from our and other laboratories has shown that many koniocellular-pathway cells receive functional connections from short-wavelength sensitive (blue) cone photoreceptors. Thus, our study will provide new insights into the connectivity of blue-cone pathways in the fovea. Although these experiments address basic scientific questions, they can lead to improved clinical practice. Understanding the wiring diagram of the retina can inform clinical studies of conditions such as glaucoma, and helps to give a rational basis for development of treatments. For example, dysfunction in blue-cone pathways is an early sign of glaucoma, so understanding the connections of blue-cone pathways in the fovea can lead to improved methods for early detection of this leading cause of blindness.Read moreRead less
Generation Of Complex Responses In Retinal Ganglion Cells
Funder
National Health and Medical Research Council
Funding Amount
$490,500.00
Summary
The retinal ganglion cells, whose axons form the optic nerve, comprise numerous distinct types, which respond to visual stimuli in either a simple or complex manner. The project will investigate how the complex responses of the direction-selective ganglion cells (DSGCs) and the local-edge-detector ganglion cells (LEDs) are generated. It appears that the retinal neurons providing inhibitory input to DSGCs and LEDs use different neurotransmitters, and the project will investigate how this shapes t ....The retinal ganglion cells, whose axons form the optic nerve, comprise numerous distinct types, which respond to visual stimuli in either a simple or complex manner. The project will investigate how the complex responses of the direction-selective ganglion cells (DSGCs) and the local-edge-detector ganglion cells (LEDs) are generated. It appears that the retinal neurons providing inhibitory input to DSGCs and LEDs use different neurotransmitters, and the project will investigate how this shapes the response properties of the ganglion cells. This will be done both by recording the visually evoked responses of the ganglion cells in an isolated preparation of the retina and by using two-photon laser-scanning microscopy to functionally image the neuronal interactions between the neurons that inhibit the DSGCs.Read moreRead less
The retina lines the back of the eye and sends multiple movies of the visual world to the brain. This project aims to investigate how these multiple information channels are created. Descriptions of the basic pattern of wiring in the healthy retina will help clinical researchers to understand the disruptions that occur in visual disease. The precision of normal retinal wiring also delineates the precision required to restore normal function to a diseased or degenerating eye.
Role Of Dendritic Information Processing In Visual Circuit Computations
Funder
National Health and Medical Research Council
Funding Amount
$895,244.00
Summary
Vision is the primary sensory modality in man, and its disturbance carries an enormous socio-economic burden. The dynamic operations of the neuronal assemblies that underlie vision are poorly understood, partly because of an incomplete description of the computational properties of visual neuronal circuits. The aims of the application are to mechanistically dissect defined computational operations of visual neural circuits using advanced electrophysiological and optical recording techniques.
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.
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.