A Brain-based Model Of Anxiety Sensitivity In Panic Disorder
Funder
National Health and Medical Research Council
Funding Amount
$402,214.00
Summary
This project will combine advanced brain imaging and brain network modelling to better understand the neurobiology of panic disorder with relevance to its treatment.
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.
How Does Chronic Epilepsy Result In Cardiac Electrophysiological Dysfunction?
Funder
National Health and Medical Research Council
Funding Amount
$737,112.00
Summary
Cardiac dysfunction is common in epilepsy, and could be an important contributor to the increased risk of sudden death in people with epilepsy (SUDEP). In this grant we will investigate: when changes in the cardiac function develop in relation to the epilepsy; if people with chronic epilepsy have similar changes; and what effect seizures and epilepsy has on the nerves innervating the heart. The outcomes have the potential to motivate new treatments and prevention for this important problem.
Probing Neural Circuits Of Emotion With Ultrafast FMRI And Dynamic Natural Stimuli
Funder
National Health and Medical Research Council
Funding Amount
$306,012.00
Summary
Emotion is central to our everyday experience and forms the backbone of our social relationships. Our understanding on emotion, however, mostly relies on strictly controlled task designs, using highly simplified and/or artificial stimuli. In this project, we propose a new platform to study brain activity underlying natural emotional experience. The design and methodology developed in this proposal will provide fundamental outcomes for understanding emotion disturbances in mental disorders.
Brain Pathways For Neurally-mediated Fever: From Vagal Afferent To Sympathetic Output To Brown Adipose Tissue Via Brain
Funder
National Health and Medical Research Council
Funding Amount
$405,223.00
Summary
Fever is one of the immune defence reactions to the invasion of microorganisms such as bacteria and viruses. Fever reflects increased heat production and decreased heat loss. Systems regulating heat production and heat loss are under brain control. To trigger fever, the immune system must alert the brain to the presence of infection. The general view of how the alerting system triggers fever is that it develops in sequential steps. Macrophages ingest microorganisms, and then regulatory proteins ....Fever is one of the immune defence reactions to the invasion of microorganisms such as bacteria and viruses. Fever reflects increased heat production and decreased heat loss. Systems regulating heat production and heat loss are under brain control. To trigger fever, the immune system must alert the brain to the presence of infection. The general view of how the alerting system triggers fever is that it develops in sequential steps. Macrophages ingest microorganisms, and then regulatory proteins (cytokines) are released. The cytokines enter the blood stream and are transported to the brain. Recently, the existence of another signalling pathway has been demonstrated. The pathway is via a special peripheral sensory nerve, the abdominal vagal sensory nerve. However, special neural pathways in the brain have not yet been clarified, even though several neural relay stations have been proposed. To elucidate neural pathways transmitting information of infection to the brain, both input and output of the pathway need to be specified. Specific outputs other than body temperature have not been determined, so far. I have recently developed a new reflex model, in which I focus on sympathetic nerves supplying the specialised fat tissue as an output as well as the vagus sensory nerve as an input. The fat tissue, brown adipose tissue (BAT), generates heat. When the vagus sensory nerve is stimulated electrically, BAT sympathetic nerve is activated. We were very exited when we discovered the potency of the combination in our rat model. We are now ready to elucidate brain pathways for neurally-mediated fever, using our new reflex model. Signalling to the brain via the nervous system is faster than via the blood stream, and thus must be very important for the earliest phase of fever. Understanding the neural pathways by which the brain perceives peripheral infection and triggers fever may promote beneficial aspects of the acute-phase immune reaction.Read moreRead less
Effectiveness Of Ghrelin Receptor Agonists To Limit The Extent Of Tissue Damage Caused By Traumatic Injury To The Central Nervous System
Funder
National Health and Medical Research Council
Funding Amount
$592,002.00
Summary
Ghrelin is a naturally occurring compound that under adverse conditions can activate specific receptors on cells around the body to enhance their survival. These receptors are also present in the spinal cord, but ghrelin doesn't enter the spinal cord. We will investigate a new group of compounds that can enter the spinal cord and activate these receptors to see if this can reduce the amount of damage that occurs after a spinal cord injury. Less tissue damage would mean less permanent disability.
We are able to identify and discriminate objects in the world because of exquisitely detailed and rapid processing of sensory information by neurons in the cortex of the brain. In this project we will examine these operations in neurons in the cortex that receive input from the large face whiskers of the rat. These whiskers are used for fine-grain discrimination and for gauging distance. They are deflected by being actively moved, under muscle control, over objects (active touch) or by being pas ....We are able to identify and discriminate objects in the world because of exquisitely detailed and rapid processing of sensory information by neurons in the cortex of the brain. In this project we will examine these operations in neurons in the cortex that receive input from the large face whiskers of the rat. These whiskers are used for fine-grain discrimination and for gauging distance. They are deflected by being actively moved, under muscle control, over objects (active touch) or by being passively deflected by objects. Deflection results in inputs to the brain that are processed to form the neural basis for very finely detailed perceptual behaviour. In rats, with impoverished visual and auditory senses, the whiskers are the major sensory system for interacting with the world, and are used in navigating the environment and in finding and distinguishing foods. Thus they contribute strongly to the remarkable success of this species. This elegant sensory system has a number of advantages that make it a very good model for the study of brain mechanisms responsible for active fine-grain sensory function. We plan to take advantage of the unique features of this system to define the information processing that occurs in the cortex in this elegantly complex system. This will address an issue relevant to all sensory systems - namely the neural basis of complex fine grain perceptual behaviour. Understanding the mechanisms underlying active tactile perception also has relevance to clinical conditions involving deficits in active touch e.g., in diabetic polyneuropathy (which eventually affects ~50% of diabetics), in leprosy (in which an early sign is damage to active touch). Knowledge of the core brain processes in active touch gained in this study could eventually underpin the ameliorative technologies for such deficits.Read moreRead less
Hypothalamic Oxexin-synthesizing Neurons Regulate The Ultradian Basic Rest-Activity Cycle (BRAC); Studies In Transgenic Rats And Mice
Funder
National Health and Medical Research Council
Funding Amount
$588,418.00
Summary
In the hypothalamus region of the brain there is a group of neurons that synthesize a neuropeptide messenger called orexin. In humans, malfunction of orexin neurons results in narcolepsy (abnormal sleepiness) and in disordered metabolism resulting in obesity. Our experiments, conducted in genetically-modified rats and mice, will elucidate the manner in which the orexin neurons integrate our behaviour (eg eating) with our physiological state (eg body and brain temperature, arterial blood pressure ....In the hypothalamus region of the brain there is a group of neurons that synthesize a neuropeptide messenger called orexin. In humans, malfunction of orexin neurons results in narcolepsy (abnormal sleepiness) and in disordered metabolism resulting in obesity. Our experiments, conducted in genetically-modified rats and mice, will elucidate the manner in which the orexin neurons integrate our behaviour (eg eating) with our physiological state (eg body and brain temperature, arterial blood pressure).Read moreRead less
Rhombomeric Topography of Structures in the Adult Mouse: Evidence from Avian Homologies and Transgenic Mice. The brainstem of birds has been shown to be formed by a line of segments, like carriages of a train. The same arrangement exists in the embryos of mammals, but is hidden in the adult mammalian brain. We will transfer our detailed knowledge of bird brains to make a maps of the brainstem segments in adult mice. We will then test this map with special gene markers which will reveal the occul ....Rhombomeric Topography of Structures in the Adult Mouse: Evidence from Avian Homologies and Transgenic Mice. The brainstem of birds has been shown to be formed by a line of segments, like carriages of a train. The same arrangement exists in the embryos of mammals, but is hidden in the adult mammalian brain. We will transfer our detailed knowledge of bird brains to make a maps of the brainstem segments in adult mice. We will then test this map with special gene markers which will reveal the occult segmental pattern in adult mice. This work will give us a new way of understanding the organisation of brainstem centres that control breathing, cardiovascular functions and emotional states.Read moreRead less
How the brain regulates blood pressure. This project will test whether a group of nerve cells in the rostral ventrolateral medulla generate sympathetic activity in blood vessels. The brain regulates blood pressure through several pathways, including nerves in the sympathetic nervous system that constrict blood vessels and increase the heart rate. Activity of these sympathetic nerves regulates blood pressure, but it is unknown which nerve cells in the brain cause this activity. This information i ....How the brain regulates blood pressure. This project will test whether a group of nerve cells in the rostral ventrolateral medulla generate sympathetic activity in blood vessels. The brain regulates blood pressure through several pathways, including nerves in the sympathetic nervous system that constrict blood vessels and increase the heart rate. Activity of these sympathetic nerves regulates blood pressure, but it is unknown which nerve cells in the brain cause this activity. This information is essential to understand how blood pressure is controlled under healthy conditions.Read moreRead less