Organization And Function Of Primate Auditory Cortex
Funder
National Health and Medical Research Council
Funding Amount
$271,671.00
Summary
The conscious perception of speech and other sounds depends on processing within a brain region known as the auditory cortex. Compared to other brain areas, relatively little is known about the organization and function of this structure. Recent studies have proposed that the auditory cortex may be anatomically subdivided into functional modules, each of which is specialized for processing different types of information. However, the evidence for multiple processing streams is fragmentary, and n ....The conscious perception of speech and other sounds depends on processing within a brain region known as the auditory cortex. Compared to other brain areas, relatively little is known about the organization and function of this structure. Recent studies have proposed that the auditory cortex may be anatomically subdivided into functional modules, each of which is specialized for processing different types of information. However, the evidence for multiple processing streams is fragmentary, and not entirely consistent. The proposed experiments will combine anatomical and physiological approaches to evaluate the functional organization of auditory cortex in the primate brain. We will map the electrical responses of single brain cells to various complex sounds across the brain surface, and inject dyes to label pathways linking brain areas to one another. The data will allow us to determine whether specific subdivisions of the auditory cortex are specialized for processing different types of infomation, and whether specific subdivisions are linked together to form processing streams specialized for sound recognition and space perception. The results will advance our understanding of the neuronal processing involved in the perception of sound, with possible implications for speech perception. This will help to understand the consequences of brain damage, and may inform the development of hearing aids and artificial voice recognition systems. In addition, this study will help to develop a primate model for studying brain mechanisms of sound recognition that should be useful in research on cochlear implants.Read moreRead less
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.
Optimising And Applying Ocular Vestibulat Evoked Myogenic Potentials (oVEMPs)
Funder
National Health and Medical Research Council
Funding Amount
$228,931.00
Summary
This project seeks to optimise techniques for a new method of assessing the balance organs (vestibular organs) and then apply these techniques. Three conditions will be studied: vestibular neuritis - a condition causing acute and severe dizziness; Parkinson's disease, in which disorders of balance are common and superior canal dehiscence (SCD) in which there is a hole in the bone overlying one of the semicircular canals, leading to sensitivity to sound.
Improving Oral health is a priority of the NHMRC Strategic Plan 2003-06. The proposed research is consistent with this priority as we will achieve a better understanding of the cortical control of human jaw muscles, which serves as the foundation for understanding conditions in which their function is impaired, and the development of rational therapies for these conditions. Transcranial magnetic stimulation will be used to activate the motor cortex and corticobulbar descending pathway to the jaw ....Improving Oral health is a priority of the NHMRC Strategic Plan 2003-06. The proposed research is consistent with this priority as we will achieve a better understanding of the cortical control of human jaw muscles, which serves as the foundation for understanding conditions in which their function is impaired, and the development of rational therapies for these conditions. Transcranial magnetic stimulation will be used to activate the motor cortex and corticobulbar descending pathway to the jaw muscles. The AIM 1 study will provide important new information about the functional organisation of the motor cortex in the control of jaw muscles during speech. This information is needed to improve understanding of dysarthria, a common disturbance of speech due to impaired muscular control following unilateral cortical stroke, and less common conditions involving speech motor control such as spasmodic dysphonia (a cranial dystonia) and dysprosody (disturbance of speech articulation and rhythm found in Parkinson s disease). The AIM 2 and 3 studies will provide a comprehensive characterization of cortical inhibitory mechanisms that are an important but poorly understood component of the cortical control of jaw muscles. This information is necessary to understand normal function, and the mechanisms of disturbances to jaw muscle function with neurological disease or injury. The AIM 4 studies will show whether impaired cortical inhibition contributes to the pathophysiology of two poorly understood disorders affecting jaw muscles (bruxism and oromandibular dystonia). Current therapies for these conditions are unsatisfactory, due to a limited understanding of the mechanisms involved. If cortical inhibition is abnormal in these conditions this will lead to novel treatment therapies (e.g., drugs to correct the imbalance, or strategies to induce plastic change in the cortex).Read moreRead less
Is EphA4 The Major Molecular Regulator Of Axonal Regeneration?
Funder
National Health and Medical Research Council
Funding Amount
$491,000.00
Summary
Spinal cord injury affects a substantial number of Australians each year. Around half the number of spinal cord injury cases result in quadriplegia, with loss of function to a varying degree in the upper as well as the lower limbs. The limited degree of repair of spinal axons following injury means that such paralysis is usually permanent. Although the inability to walk is a serious issue, the limited function of the arms and hands results in a loss of independence which is a major factor contri ....Spinal cord injury affects a substantial number of Australians each year. Around half the number of spinal cord injury cases result in quadriplegia, with loss of function to a varying degree in the upper as well as the lower limbs. The limited degree of repair of spinal axons following injury means that such paralysis is usually permanent. Although the inability to walk is a serious issue, the limited function of the arms and hands results in a loss of independence which is a major factor contribuing to the enormous personal, financial, and community costs of this problem, estimated to cost the Australian community $200 million a year. In recent years advanced anatomical and molecular approaches to the problem of repair of the central nervous system have provided great insights into the neuronal and glial reactions to neural damage that appear to govern the success or failure of neural regeneration. Our preliminary data indicate that a receptor tyrosine kinase, EphA4, which is important for axonal pathfinding in the developing nervous system, is a potent inhibitor of neural regeneration following spinal cord injury. In this project we will determine the mechanisms by which EphA4 exerts its inhibitory effects, and examine the effect of neutralizing EphA4 signalling on neural regeneration. Success in achieving this result will lead to the development of a therapeutic intervention that we will test in mouse models.Read moreRead less
An inability to resist a temptation or repeated failures of self-regulation can lead to 'impulsive' and 'compulsive' behaviours that relate to a host of personal and social problems (eg., excessive eating, gambling, and substance use). Despite this, very little research has studied the neural and psychological underpinnings of these behaviours. My research will take advantage of recent innovations and approaches to fill this void and have implications for diagnosis and treatment.