THE EFFECTS OF TRANSCRANIAL MAGNETIC STIMULATION (TMS) ON RAT MODELS OF DEPRESSION
Funder
National Health and Medical Research Council
Funding Amount
$204,274.00
Summary
Repetitive Transcranial Magnetic Stimulation (rTMS) is the direct stimulation of the brain by using high field magnetic pulses. It is a new technique that has been demonstrated to have some potential as a treatment of depressive illness and possibly other neuropsychiatric disorders. At this early stage of its investigation, the parameters of stimulation that are most likely to be therapeutic, and its mechanisms of action, are not known. Published studies vary in the frequency, duration and exten ....Repetitive Transcranial Magnetic Stimulation (rTMS) is the direct stimulation of the brain by using high field magnetic pulses. It is a new technique that has been demonstrated to have some potential as a treatment of depressive illness and possibly other neuropsychiatric disorders. At this early stage of its investigation, the parameters of stimulation that are most likely to be therapeutic, and its mechanisms of action, are not known. Published studies vary in the frequency, duration and extent of stimulation, with no firm guidelines about optimal parameters. Empirical study of the relative effects of stimulation at different frequencies, at different numbers of stimuli and for different durations is therefore important for the future development of this treatment. Such an investigation is best carried out in an animal model of depression for both ethical and practical reasons, as such studies in patients would possibly take many years and be extremely difficult to conduct. We propose such a study in rat models of depression which have demonstrated validity and utility in drug research. Rat models have a long track record in developing psychiatric treatments and are cost-effective and of proven value. We also plan to investigate the neuroanatomy of the immediate-early genes induced by TMS and compare it with electroconvulsive shock (ECS) and a tricyclic antidepressant, two established treatments of depression. The results will have implications for future human studies in guiding us toward the optimal parameters for therapeutic effects. They will also enhance our understanding of the mechanism of action of TMS in depression.Read moreRead less
THE NATURAL HISTORY OF COGNITIVE IMPAIRMENT AND DEMENTIA IN A STROKE COHORT
Funder
National Health and Medical Research Council
Funding Amount
$290,747.00
Summary
In a current NHMRC-funded study, we have examined 200 stroke patients (and 100 control subjects) at 3 months after a stroke and one year later, and identified those who have impairment in memory and other cognitive functions. We have also studied these subjects in detail from a psychiatric perspective and performed brain scans on them using magentic resonance imaging. We find that many stroke patients have problems with their cognitive functioning which has a major impact on their lives. A large ....In a current NHMRC-funded study, we have examined 200 stroke patients (and 100 control subjects) at 3 months after a stroke and one year later, and identified those who have impairment in memory and other cognitive functions. We have also studied these subjects in detail from a psychiatric perspective and performed brain scans on them using magentic resonance imaging. We find that many stroke patients have problems with their cognitive functioning which has a major impact on their lives. A large number also become depressed. These consequences of stroke are not given sufficient importance by clinicians. The fact that stroke is a common problem in the elderly, and our society is aging, makes this a problem of major public health significance. In the new proposal, we plan to study these subjects up to 3 years with repeat neuropsychiatric assessments and brain scans to investigate the natural history of stroke-related cognitive impairment. We will determine whether further new cases of dementia develop in the period 1-3 years, what happens to the brain lesions picked up on brain scans, and how these deficiencies affect the patients' living status and their longevity. We will be able to determine the factors that lead to a good outcome, and suggest strategies that may be applicable to improve the functioning of these individuals.Read moreRead less