Mechanisms And Treatment Of Upper Airway Collapse In Obstructive Sleep Apnoea
Funder
National Health and Medical Research Council
Funding Amount
$328,668.00
Summary
Obstructive sleep apnoea (OSA) is characterized by intermittent closure of the upper airway (throat) resulting in episodes of decreased blood oxygen levels, increased blood pressure and disturbed sleep. Repetitive overnight arousals from sleep cause excessive daytime tiredness and lethargy, which have major consequences for social well-being and productivity in our community. OSA is a common condition, affecting as many as 2 to 4% of middle aged adults, and is associated with an increased cardio ....Obstructive sleep apnoea (OSA) is characterized by intermittent closure of the upper airway (throat) resulting in episodes of decreased blood oxygen levels, increased blood pressure and disturbed sleep. Repetitive overnight arousals from sleep cause excessive daytime tiredness and lethargy, which have major consequences for social well-being and productivity in our community. OSA is a common condition, affecting as many as 2 to 4% of middle aged adults, and is associated with an increased cardiovascular risk, however the mechanisms underlying the increased upper airway collapsibility in individuals with OSA are not well understood. The proposed studies represent a series of investigations into fundamental mechanisms of neural and mechanical control of upper airway patency, how these mechanisms act to stabilize the upper airway, and whether these reflex control mechanisms can be manipulated to provide a novel treatment for OSA.Read moreRead less
Human Muscle Stretch Reflexes: The Effects Of Stimulus Properties, Muscle State And Subject Intention
Funder
National Health and Medical Research Council
Funding Amount
$170,604.00
Summary
The best known muscle reflex is the tendon jerk, which is usually evoked by tapping the muscle tendon with a small hammer. This tap imposes a very rapid stretch on the muscle, which produces a stretch reflex. Different stretch responses, however, can be observed to slow or fast stretches, or to vibration of muscle. Normally, when the muscles of a relaxed person are stretched, no active response is observed. However, when the person is engaged in a task and contracting their muscles, then stretch ....The best known muscle reflex is the tendon jerk, which is usually evoked by tapping the muscle tendon with a small hammer. This tap imposes a very rapid stretch on the muscle, which produces a stretch reflex. Different stretch responses, however, can be observed to slow or fast stretches, or to vibration of muscle. Normally, when the muscles of a relaxed person are stretched, no active response is observed. However, when the person is engaged in a task and contracting their muscles, then stretch modulates the muscle activity such that an increase in contraction of the muscle opposes the stretch and defends the position of the joint against the external disturbance. This is the everyday situation in which stretch reflexes operate. Despite extensive investigation for over a hundred years, there is still no consensus among researchers about the behaviour of stretch reflexes nor about their role in the control of movement. Even the demarcation of reflex from voluntary muscle activity is not always certain. One of the outstanding features of stretch reflexes is the variability of their behaviour, which depends on the particular muscle involved, its level of contraction, the type of stretch and the task in which the person is engaged. This variability has made it difficult for researchers to determine the role of reflexes in the control of movement. In order to study stretch reflex behaviour in human subjects, we will measure the electrical activity of elbow muscles, the elbow position and the force generated at the joint under a variety of conditions. A series of five experiments will investigate specific unresolved issues such as the effect of subject intention on the modulation of muscle activity and how altered modulation of muscle activity may change the stiffness of our limbs. The objective of the experimental series is to fill in important gaps in the picture of the behaviour of the stretch reflex.Read moreRead less
Neural Connectivity In Young People At High Risk Of Developing Psychosis
Funder
National Health and Medical Research Council
Funding Amount
$331,972.00
Summary
This project will investigate whether or not young people at high risk of developing psychosis show irregularities in the connections between different parts of their brain. It will also investigate whether information about a high-risk individual’s brain connectivity can be used to predict a) whether that person will make the transition to psychosis, and b) their clinical prognosis if they do become psychotic.
Erythrocyte Membrane Fatty Acid Concentrations And Myelin Integrity In Young People At Ultra-High Risk Of Psychosis
Funder
National Health and Medical Research Council
Funding Amount
$406,831.00
Summary
Polyunsaturated fatty acids (PUFAs) play an important role in many physiological processes in all organisms. Myelination is the process by which a fatty layer, called myelin, accumulates around nerve cells enabling nerve cells to transmit information faster. PUFAs are essential for myelination, and there is evidence documenting decreased PUFA concentrations and brain white matter (myelin) pathology in people with schizophrenia. The mechanisms underlying these abnormalities are not understood.