Standardisation Of Prepulse Inhibition Of The Startle Reflex For Pharmacological And Interspecies Comparisons
Funder
National Health and Medical Research Council
Funding Amount
$252,761.00
Summary
People and other animals startle when they here a sudden loud sound. How much one startles depends in part on how loud the sound is. The relationship between the loudness of the sound and the size of the startle resembles a ski slope. Each individual has a ski slope that differs from others; the beginning of the ski slope (threshold) occurs at a different loudness, the slope is a different steepness, and the height of the ski slope where the plateau occurs is different. There are genetic differe ....People and other animals startle when they here a sudden loud sound. How much one startles depends in part on how loud the sound is. The relationship between the loudness of the sound and the size of the startle resembles a ski slope. Each individual has a ski slope that differs from others; the beginning of the ski slope (threshold) occurs at a different loudness, the slope is a different steepness, and the height of the ski slope where the plateau occurs is different. There are genetic differences in ski slopes as well. The size of the startle reflex can also be reduced by preceding the startling sound with a quiet stimulus a few tens of milliseconds before the startling stimulus. This is known as prepulse inhibition of the startle reflex or PPI for short. There is much interest in PPI, because it differs in people with certain mental illnesses, such as schizophrenia or post-traumatic stress disorder, and certain neurological illnesses, such as Huntington's chorea. It is also affected by drugs, including stimulants, stress hormones, and cannabis. In almost all the hundreds of experiments on PPI the effect of the prepulse on the response to a startling stimulus is measured at only one startling stimulus loudness. This loudness can be at very different parts of the ski slope for different people or other animals: it may be in the steep slope for one person, well into the plateau for another, or even at the bottom of the ski slope below the threshold in others. The effect of PPI is very different depending on what part of the ski slope the loudness represents. A lack of consistent effects in the literature on PPI by drugs and genetics is explained by this difference. Experiments are planned that will investigate the effect of drugs that are similar to those that treat schizophrenia, stress hormones and cannabis on the effect of prepulses on the whole ski slope. This procedure will provide the consistency in results so far absent.Read moreRead less
Neural Circuits For Residual Vision After Damage To Striate Cortex
Funder
National Health and Medical Research Council
Funding Amount
$662,220.00
Summary
Brain cells have the ability to rearrange their connections to create alternate pathways, which compensate for loss of function following brain damage. To understand why some people become blind after damage to the visual cortex, and some don't, we will determine how neural connections change following lesions in different stages of life. The project will provide important information that may allow future development of treatments for blindness due to stroke or traumatic brain injury.
The Orexin System: A Link Between Addiction And Depression
Funder
National Health and Medical Research Council
Funding Amount
$378,426.00
Summary
Relapse represents the most significant barrier to the successful treatment of addiction Interestingly, relapse rates are significantly higher amongst addicts with a concurrent mood disorder such as depression. This fellowship will use a number of cutting-edge techniques to explore the role of a hypothalamic peptide called 'orexin' in both relapse and depression and will thereby guide translational research aimed at developing pharmacotherapies designed to treat these disorders.
Neural Circuits For Active Vision In The Primate Cerebral Cortex
Funder
National Health and Medical Research Council
Funding Amount
$632,938.00
Summary
This project will try to understand how we use visual information to identify objects by their shape and motion, in natural situations in which the eyes are moving all the time. This will be accomplished by recording the electrical activity of brain cells while a trained animal is performing different types of tasks, such as tracking a moving object or exploring a scene with its eyes.
Down syndrome (DS) individuals have 3 copies of chromosome 21. I am proposing to do my PhD to investigate the role of a gene existing on chromosome 21 called Intersectin 1. This gene, when over-expressed might be responsible for manifestation of intellectual impairment in Down syndrome. I will be examining the consequence of altered/over-expression of this gene in receptor trafficking, cell signalling and histology of the brain to identify the differences between affected individuals and the nor ....Down syndrome (DS) individuals have 3 copies of chromosome 21. I am proposing to do my PhD to investigate the role of a gene existing on chromosome 21 called Intersectin 1. This gene, when over-expressed might be responsible for manifestation of intellectual impairment in Down syndrome. I will be examining the consequence of altered/over-expression of this gene in receptor trafficking, cell signalling and histology of the brain to identify the differences between affected individuals and the normal population.Read moreRead less
How The Lateral Habenula Integrates Behavioral And Autonomic Functions: The VTA Dopamine Connection
Funder
National Health and Medical Research Council
Funding Amount
$819,904.00
Summary
When adverse events occur, the lateral habenula, an old brain nucleus, helps calculate the wisest corrective action by contributing to the “brake” that controls the brain’s dopamine reward system. Our research will show how the lateral habenula links corrective changes in behavior with coordinated changes in temperature. Understanding this link will greatly contribute to understanding the brain mechanisms that regulate our physiology during stressful situations and as part of mental illness.
Pain has a detrimental impact on ones quality of life and a significant financial impact on the community. Although some of the pathways that code pain in the brain have been defined, it was recently proposed that there also exists a pain-specific pathway in humans. Using human brain imaging, we aim to determine if such a pathway exists and if it is altered in subjects with chronic pain. The existence of such a pathway would significantly aid in the development of better treatment regimes.
The mammalian cerebral cortex is an area of the brain responsible for all higher order cognitive processes. I investigate how connections from between the two cerebral hemispheres during embryonic and foetal development, thus enabling the brain to coordinate information from the two sides of the body. Malformations of these connections cause mental retardation and sensory and motor deficits. I want to understand how these brain defects occur and how best to treat them.
Activity In Central Cough Networks In Patients With Cough Hypersensitivity
Funder
National Health and Medical Research Council
Funding Amount
$459,499.00
Summary
Excessive cough associated with an airways disease represents the most common reason for doctor consultations. However, the current therapeutic options for relieving excessive cough are limited. This proposal will provide unprecedented insights into the brain mechanisms that contribute to the development of cough disorders in airways disease.
Development of normal brain function requires information transfer and integration from outside and within the brain. Normal brain wiring is guided by genetic and environmental cues, whose relative contributions remain controversial. This project investigates the physiological and behavioural consequences of abnormal brain wiring, and the potential for controlled environments and targeted interventions to overcome the deficits. Relevance includes neurotrauma as well as mental illnesses.