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
Sympathetic Control Of Cutaneous Blood Flow And Blood Pressure In Human Spinal Cord Injury
Funder
National Health and Medical Research Council
Funding Amount
$242,002.00
Summary
While spinal cord injury can cause devastating changes in the nervous system paralysis and loss of sensation relatively little is known about changes to the sympathetic nervous system. The sympathetic nervous system is intimately involved in the ongoing control of blood pressure, blood flow and temperature control. Loss of sympathetic control can occur following spinal cord injury. Interruption of descending pathways can result in partial or complete loss of sympathetic outflow from the thoracol ....While spinal cord injury can cause devastating changes in the nervous system paralysis and loss of sensation relatively little is known about changes to the sympathetic nervous system. The sympathetic nervous system is intimately involved in the ongoing control of blood pressure, blood flow and temperature control. Loss of sympathetic control can occur following spinal cord injury. Interruption of descending pathways can result in partial or complete loss of sympathetic outflow from the thoracolumbar segments. Complete decentralization can result in autonomic dysreflexia (autonomic hyperreflexia), in which sensory stimuli originating below the lesion evoke a reflex increase in sympathetic drive to the blood vessels, causing them to constrict. Because of this, blood pressure may rise suddenly and remain at such high levels that stroke and (occassionally) cardiac arrest may occur. This phenomenon, autonomic dysreflexia, is considered a medical emergency. The typical subjective signs of autonomic dysreflexia include a throbbing headache, tingling in the head or nasal congestion; sweating and flushing above the lesion are clinical signs that prompt medical staff to measure blood pressure and to locate the source of sensory irritation (usually a distended bladder or impacted colon, sometimes a pressure sore or ingrown toenail). Commonly, however, subclinical episodes go undetected, and this phenomenon of silent dysreflexia is of increasing concern. This project will develop means of assessing the integrity and state of the sympathetic nervous system below a lesion in patients with spinal cord injury and characterize the firing properties of reflexly activated sympathetic neurones.Read moreRead less
Towards a continuum model of orienting and defensive responses. Orienting (OR) and Defensive Responses (DR) underlie important survival functions of attending to unexpected stimuli and avoiding harm.We will establish the first integrative profile of human OR/DR function, using simultaneous recording of brain activity and 'body' responsivity. Given sex and age variation in OR/DRs, both males and females spanning six decades will be studied. OR/DR abnormalities are associated with major disorders ....Towards a continuum model of orienting and defensive responses. Orienting (OR) and Defensive Responses (DR) underlie important survival functions of attending to unexpected stimuli and avoiding harm.We will establish the first integrative profile of human OR/DR function, using simultaneous recording of brain activity and 'body' responsivity. Given sex and age variation in OR/DRs, both males and females spanning six decades will be studied. OR/DR abnormalities are associated with major disorders of attention and stress, which also vary with sex and age. We will examine relationships between OR/DR function and proneness to these disorders in healthy individuals. The results will provide a framework for developing prevention and intervention strategies.Read moreRead less
Exploring the brain mechanisms underlying hyperactivity in Attention-Deficit/Hyperactivity Disorder. Attention-deficit/Hyperactivity Disorder (AD/HD) is the most common psychiatric disorder affecting children, resulting in substantial costs (both human and financial) to the child, their family and Australian society. The outcomes of this project will provide a better foundation for understanding dysfunctional brain mechanisms in AD/HD, which is expected to lead to better diagnosis, treatment, an ....Exploring the brain mechanisms underlying hyperactivity in Attention-Deficit/Hyperactivity Disorder. Attention-deficit/Hyperactivity Disorder (AD/HD) is the most common psychiatric disorder affecting children, resulting in substantial costs (both human and financial) to the child, their family and Australian society. The outcomes of this project will provide a better foundation for understanding dysfunctional brain mechanisms in AD/HD, which is expected to lead to better diagnosis, treatment, and community support. Ultimately this will contribute to a healthy start to life for these children. This project will also demonstrate how an integrated Australian approach can lead the research agenda in both basic neuroscience, at the interface of psychology and physiology, and its applications in health.Read moreRead less
The implications of resistance training for the control of movement. Resistance training (or weight lifting) is an essential element of comprehensive rehabilitation programs in a wide range of clinical settings. However, because we know little about how the organization of the nervous system is affected by training with high loads, the consequences of resistance training for our ability to control functional movements are unclear. The ultimate goal of this research is to generate basic knowledge ....The implications of resistance training for the control of movement. Resistance training (or weight lifting) is an essential element of comprehensive rehabilitation programs in a wide range of clinical settings. However, because we know little about how the organization of the nervous system is affected by training with high loads, the consequences of resistance training for our ability to control functional movements are unclear. The ultimate goal of this research is to generate basic knowledge about the impact of resistance training on nervous system function. The research will lead to the design of injury prevention and rehabilitation programs that are maximally effective, and provide a genuine benefit to the community.Read moreRead less
Learning about threats: the neural and behavioural response to predator-related cues in rodents. This project will investigate the anxiety displayed by rats when confronted with the odours of predators such as cats. This anxiety may be very similar to that experienced by humans who suffer from anxiety disorders such as phobias. By investigating the nature of this anxiety, the nature of the stimuli that produce it, and the learning and neural processes that underlie it we may better understand h ....Learning about threats: the neural and behavioural response to predator-related cues in rodents. This project will investigate the anxiety displayed by rats when confronted with the odours of predators such as cats. This anxiety may be very similar to that experienced by humans who suffer from anxiety disorders such as phobias. By investigating the nature of this anxiety, the nature of the stimuli that produce it, and the learning and neural processes that underlie it we may better understand human anxiety. The project also aims to identify novel chemicals in the fur of cats that have rodent repellent properties. Such chemicals may be of great use in domestic and agricultural contexts where rodents are pests.Read moreRead less
Inhibition Of Fear Memories By Extinction: Neural Substrates.
Funder
National Health and Medical Research Council
Funding Amount
$234,250.00
Summary
Anxiety disorders [e.g., Post Traumatic Stress Disorder (PTSD)] are the most prevalent type of psychopathology in the industrialised world. They are associated with characteristic behavioural (e.g., heightened startle) and autonomic (e.g., cardiovascular) reactions. These disorders are often characterised as an inability to regulate the emotion of fear. Significant progress has been made in understanding the neural and cellular processes involved in the establishment of fear memories, but relati ....Anxiety disorders [e.g., Post Traumatic Stress Disorder (PTSD)] are the most prevalent type of psychopathology in the industrialised world. They are associated with characteristic behavioural (e.g., heightened startle) and autonomic (e.g., cardiovascular) reactions. These disorders are often characterised as an inability to regulate the emotion of fear. Significant progress has been made in understanding the neural and cellular processes involved in the establishment of fear memories, but relatively little is known about the mechanisms by which fear memories can be inhibited or suppressed. Understanding this latter process is a key to the development of effective treatments for anxiety disorders such as PTSD where the patient suffers from persistent, intrusive, unwanted trauma memories. A common experimental procedure for reducing learned fear is to repeatedly expose the subject to a fear-eliciting stimulus but without any aversive outcome. This procedure leads to a progressive loss, or extinction, of the fear reactions elicited by the stimulus. Historically, the extinction of fear was thought to be due to an erasure of the fear memory. However, recent evidence shows that extinction inhibits, rather than erases, the fear memory. Because the fear memories remain intact, some structure(s) in the brain must inhibit activity in the fear pathway. This project uses extinction of conditioned fear reactions in rat subjects to determine the structure(s) in the brain that inhibit fear memories and their behavioural and cardiovascular expression. It brings together the expertise of four well-established researchers and uses a combination of behavioural, physiological, immunohistochemical, tract tracing, and lesion approaches to achieve this aim. The proposed experiments will reveal the structure(s) in the brain that control the inhibition of fear, as well as the site(s) of this inhibition in the fear pathwayRead moreRead less
The structure and function of the human spinal connectome. This project will use complex network analysis to map the interactions between the brain and body, to understand how the central nervous system controls our movements. The project will provide fundamental insights into mechanisms that coordinate activity in the human motor system, and how the breakdown of coordination may lead to movement disorders. By integrating advanced computational analyses with state-of-the-art recording techniques ....The structure and function of the human spinal connectome. This project will use complex network analysis to map the interactions between the brain and body, to understand how the central nervous system controls our movements. The project will provide fundamental insights into mechanisms that coordinate activity in the human motor system, and how the breakdown of coordination may lead to movement disorders. By integrating advanced computational analyses with state-of-the-art recording techniques, the project will generate new knowledge of the neural basis of human motor coordination. Expected outcomes may support future applications to restore motor function through brain stimulation, prosthetics and robotics design.Read moreRead less
INVESTIGATION OF A BRAIN RHYTHM. Elucidation of brain function remains a frontier for human discovery. To date, research has largely focussed on brain connectivity with major advances in knowledge of input/output function of brain regions. Yet, there remains little understanding of higher order processes that underlie functions such as mood states and consciousness. Investigation of brain rhythms represent a step to unravelling such processes, as rhythms both act as autonomous clocks and generat ....INVESTIGATION OF A BRAIN RHYTHM. Elucidation of brain function remains a frontier for human discovery. To date, research has largely focussed on brain connectivity with major advances in knowledge of input/output function of brain regions. Yet, there remains little understanding of higher order processes that underlie functions such as mood states and consciousness. Investigation of brain rhythms represent a step to unravelling such processes, as rhythms both act as autonomous clocks and generate synchronised neuronal activity. This project aims to investigate mechanisms underlying a specific class of brain rhythm implicated in control of mood states. Positive outcomes from this basic research may lead to better drug therapies for controlling specific mental disorders.Read moreRead less