The Effect Of Adenotonsillectomy On Neurocognitive Functioning In Children With Upper Airway Obstruction
Funder
National Health and Medical Research Council
Funding Amount
$185,850.00
Summary
Upper airway obstruction during sleep affects up to 3% of all children and is very frequently unrecognised. If severe it causes growth failure, developmental delay and heart failure. However, there is little information on the effects of less severe degrees of upper airway obstruction in children but recent work suggests that reduced academic performance may also be present in children with relatively mild degrees of upper airway obstruction. In particular, the areas most affected appear to be i ....Upper airway obstruction during sleep affects up to 3% of all children and is very frequently unrecognised. If severe it causes growth failure, developmental delay and heart failure. However, there is little information on the effects of less severe degrees of upper airway obstruction in children but recent work suggests that reduced academic performance may also be present in children with relatively mild degrees of upper airway obstruction. In particular, the areas most affected appear to be intelligence, memory, behaviour and attentional capacity . Currently it is unclear whether these deficits are due to sleep disruption or reduced nocturnal oxygen levels. The treatment of upper airway obstruction is the removal of adenoids and tonsils, however, it is unknown whether or not this improves the child's intellectual capacity. This study aims to be one of the first to critically evaluate the impact of upper airway obstruction during sleep on children's intelligence, memory, behaviour and attentional capacity, and the improvements wrought by the removal of the child's tonsils and adenoids.Read moreRead less
If Childhood Primary Snoring Resolves, Do Neurocognition And Behaviour Also Improve?
Funder
National Health and Medical Research Council
Funding Amount
$568,067.00
Summary
Sleep breathing disorders (SBD) are common and affect around 10% of all children. Previous research however has shown that sleep disorders are often not recognised or considered important enough to report to general practitioners. Thus, the true incidence of sleep disorders in Australian children is not known. Nevertheless, even the mildest SBD, primary snoring, has been associated with significant deficits in daytime learning, memory, intelligence, attention and problematic behaviour. In severe ....Sleep breathing disorders (SBD) are common and affect around 10% of all children. Previous research however has shown that sleep disorders are often not recognised or considered important enough to report to general practitioners. Thus, the true incidence of sleep disorders in Australian children is not known. Nevertheless, even the mildest SBD, primary snoring, has been associated with significant deficits in daytime learning, memory, intelligence, attention and problematic behaviour. In severe cases of childhood SBD (i.e. sleep apnoea syndrome), removal of the tonsils and adenoids has been shown to improve the learning and behaviour problems. Thus there is increasing pressure on doctors to treat primary snoring in children with surgery to improve their intellectual functioning. However, recent evidence in children has shown that snoring may resolve naturally in up to 50% of cases over one to two years. In addition to the risks of surgery, the large number of children who may have a natural resolution of snoring suggestst that the pressure to treat primary snoring in may not be justified. This study will be the first to determine the prevalence of childhood snoring and associated problems in the Australian community. We also aim to discover whether snoring and the associated intellectual deficits persist over time during childhood. We will identify frequent snorers and healthy non-snorers in children aged 5-10 years old, using parental questionnaires. We will then study 75 snorers and 75 non-snorers in more detail, monitoring them with overnight sleep studies and questionnaires 2 years apart, to see if snoring, intellectual function and behavioural problems persist over time. This information will improve the health of Australian children by determining the prevalence of childhood SBD and persistence of associated deficits such as in learning, memory and behaviour.Read moreRead less
Neurocognitive Studies Of Reward Sensitivity In Opiate Addiction And Its Influence On Addiction-related Behaviour
Funder
National Health and Medical Research Council
Funding Amount
$258,275.00
Summary
Drug abuse is the greatest single preventable risk factor for physical illness and death in Australians . Our understanding of the neural and cognitive mechanisms that contribute to the transition from drug use to addiction is not yet complete. The current proposal investigates cognitive control dysfunction, most notably the impulsivity for reward seen in drug addiction that is known to predict the transition from drug use to addiction and relapse during treatment.
Organic Brain Damage After Non-fatal Opioid Overdose
Funder
National Health and Medical Research Council
Funding Amount
$244,858.00
Summary
The study will provide the first data on the level and nature of brain damage due to opioid overdose. The extent to which overdose survivors suffer brain damage has important implications for clinical management, particularly in relation to behavioural problems. It will also provide the first data on brain damage and drug treatment performance. Screening of those with an overdose history may lead to specialised management of these individuals with the potential for improved treatment outcome.
Neurocognitive Studies Of Brain Plasticity Associated With Surgical Treatment Of Arteriovenous Malformations
Funder
National Health and Medical Research Council
Funding Amount
$701,922.00
Summary
We will use state-of-the-art brain imaging methods to test whether specific brain areas which have been chronically starved of adequate blood supply can regenerate, informing debate about limits on brain plasticity. Arteriovenous malformations (AVMs) are longstanding defects which can cause thinking skills to 'migrate' to other brain regions in childhood without noticeable impact. Surgical correction allows a test of what happens to the previously inactive area: Does the area 'start to think'?
Muscarinic M1 Receptor, Cognition And Schizophrenia
Funder
National Health and Medical Research Council
Funding Amount
$598,800.00
Summary
Schizophrenia is a serious psychiatric illness that affects approximately 1% of Australia's population. Whilst the prominent symptom of schizophrenia is psychosis, the majority of subjects with schizophrenia also show deficits in cognition. Unlike psychotic symptoms, deficits in cognition do not respond well to current antipsychotic drug treatment. We have been investigating the possible role for changes in a family of receptors, called muscarinic receptors, in the pathology of schizophrenia for ....Schizophrenia is a serious psychiatric illness that affects approximately 1% of Australia's population. Whilst the prominent symptom of schizophrenia is psychosis, the majority of subjects with schizophrenia also show deficits in cognition. Unlike psychotic symptoms, deficits in cognition do not respond well to current antipsychotic drug treatment. We have been investigating the possible role for changes in a family of receptors, called muscarinic receptors, in the pathology of schizophrenia for almost a decade. Our research has shown that two members of the muscarinic receptor family, the M1 and M4 receptors, may be differentially decreased in different brain regions of subjects with schizophrenia. Recently, we have shown that in the dorsolateral prefrontal cortex, the muscarinic receptor that is decreased in schizophrenia is the M1 receptor. Since we made this discovery another group has shown that a mutation in the M1 receptor may be a cause of cognitive deficits in schizophrenia. We are now proposing a study using parallel streams of research on postmortem brain tissue and in living subjects with schizophrenia to determine the likelihood that decreases in M1 receptors in the cortex may be the cause of cognitive deficits in schizophrenia. This will involve confirming that mutations in the M1 receptor, measured using DNA from white blood cells, are associated with cognitive deficits in schizophrenia. At the same time we will determine if the same mutation is associated with low levels of M1 receptors in cortex obtained postmortem from subjects with schizophrenia. If both these are true this will give us a strong platform to suggest that low levels of cortical M1 receptors are associated with cognitive deficits in schizophrenia.Read moreRead less
Neurocognitive And Social Changes Associated With Unleaded Petrol Sniffing And Abstinence From Further Sniffing
Funder
National Health and Medical Research Council
Funding Amount
$639,570.00
Summary
Currently, there is a poor understanding about the nature and permanence of brain damage associated with sniffing petrol. Previously, we used culturally-appropriate assessments of brain function to test Aboriginal petrol sniffers from remote communities in northern Australia. This showed that recreational petrol sniffers who remained living in their communities showed some degree of brain dysfunction that affected their ability to concentrate, remember things, learn, control their emotions and c ....Currently, there is a poor understanding about the nature and permanence of brain damage associated with sniffing petrol. Previously, we used culturally-appropriate assessments of brain function to test Aboriginal petrol sniffers from remote communities in northern Australia. This showed that recreational petrol sniffers who remained living in their communities showed some degree of brain dysfunction that affected their ability to concentrate, remember things, learn, control their emotions and control their behaviour. Petrol sniffing was then completely stopped in these communities. Two years later, among people who had shown brain dysfunction from sniffing petrol, our assessments showed some recovery of some of the brain damage caused by sniffing petrol. Initially, the current study aims to determine the longer-term outcomes for abstinent petrol sniffers by returning to these communities and assessing social and brain function outcomes in the original study participants, now over 10 years since they stopped sniffing petrol. The second part of the study will focus on the specific effects on the brain, behaviour and social function of sniffing unleaded petrol in comparison to leaded petrol, alcohol, other inhalants and polydrug use. It will also further investigate the time course of recovery of brain function and social outcomes in the immediate period following abstinence from petrol sniffing. This will involve recruiting petrol sniffers who move to outstation communities to stop sniffing, and have them perform brain function tests several times over the months or years that they spend recovering. These findings will enable the development of appropriate programs to minimise the harm from petrol sniffing. It will also establish an assessment protocol for the classification of petrol related brain damage that can be used by health professionals such as Aboriginal health workers, nurses and doctors.Read moreRead less
Abnormal Auditory System Function In Schizophrenia: An ERP And MEG Study Of Its Origin, Course And Generality.
Funder
National Health and Medical Research Council
Funding Amount
$250,770.00
Summary
In 1991, an Australian group found that schizophrenia patients have a reduced brain response to deviant sounds in a repeating pattern of identical sounds. Deviant sounds produce a brain electrical response known as mismatch negativity which is generated by the auditory cortex in the brain's temporal lobes and by adjacent areas in the frontal lobes. A smaller mismatch negativity in patients has since been replicated in laboratories in the US, Europe and Australia. The importance of this finding i ....In 1991, an Australian group found that schizophrenia patients have a reduced brain response to deviant sounds in a repeating pattern of identical sounds. Deviant sounds produce a brain electrical response known as mismatch negativity which is generated by the auditory cortex in the brain's temporal lobes and by adjacent areas in the frontal lobes. A smaller mismatch negativity in patients has since been replicated in laboratories in the US, Europe and Australia. The importance of this finding is that it had not been previously recognised that patients have low level auditory problems that could potentially have a profound impact on higher level functions. Finnish researchers have gone on to show in healthy individuals that mismatch negativity can reveal important features about how well the auditory system works, e.g., for the brain to respond to a deviant sound, it must have a memory of what happened in the past. Mismatch negativity provides a measure of the integrity of these memory functions. But it also provides an index of how well the auditory system discriminates different aspects of sound, pitch, loudness, and temporal features, such as duration. There are hints in our data and from US researchers that processing of the temporal features of sounds is particularly impaired in schizophrenia. We have also recently discovered that first-degree relatives of patients may have a similar deficit. The aim of this project is to use mismatch negativity to probe what is wrong with the auditory system in schizophrenia and those at risk (first degree relatives). Is it the areas of the brain primarily involved in sound perception (the temporal lobes) that are faulty or is the problem in the frontal lobes? Is it the case that processing of temporal features are particularly compromised and if so, is this a biological marker for schizophrenia. Answers to these questions will greatly enhance our understanding of the nature of the brain dysfunction in schizophrenia.Read moreRead less
Iron is essential for brain health. Too little iron can cause problems with memory, concentration and attention and can result in below average intellectual performance or even stroke in children. Too much iron can also be harmful. In the iron overload disease haemochromatosis, iron deposition throughout the body can lead to organ damage in the liver and other tissues. Concentrations of iron in the brain can equal those in liver. Yet surprisingly little is known about the effects of iron on the ....Iron is essential for brain health. Too little iron can cause problems with memory, concentration and attention and can result in below average intellectual performance or even stroke in children. Too much iron can also be harmful. In the iron overload disease haemochromatosis, iron deposition throughout the body can lead to organ damage in the liver and other tissues. Concentrations of iron in the brain can equal those in liver. Yet surprisingly little is known about the effects of iron on the adult human brain. Although the adult brain has traditionally been considered to be protected from the effects of high body iron by the blood-brain barrier, modern techniques show brain iron loading in patients with iron overload disorders or with various brain diseases such as Alzheimer's disease and Parkinson's disease. Several recent studies, including our own, have found associations between mutations in genes important in iron metabolism and brain diseases such as Alzheimer's disease. As many as 30% of Australians have abnormal iron levels (too high or too low) that are often undiagnosed and untreated. There is growing reason to believe these men and women are more likely to have memory problems as well as being at increased risk of brain diseases such as Alzheimer's disease. There is an urgent need for a large-scale study of the short-term and long-term effects of iron levels and related genetic factors on brain health and function. Residents of the Western Australian town of Busselton have participated in a set of health surveys since 1966. We have studied the iron status and related genetic factors in over 3,000 Busselton people. We now propose to perform tests of memory, attention, concentration and related brain activities on the older members of this community group. This will allow us to discover the effects of relevant gene factors, and short- and long-term iron status on memory and other brain functions and on Alzheimer's disease and related disorders.Read moreRead less
A Cognitive And Neuroimaging Study Of Exceptionally Old Individuals: Sydney Centenarian Study
Funder
National Health and Medical Research Council
Funding Amount
$857,197.00
Summary
Australia has an ageing society. Individuals over the age of 95 years are the fastest growing proportion of this population. Many of these individuals retain good cognitive function. The Sydney Centenarian Study will recruit all individuals 95 and over in 7 local government areas in Sydney to assess their brain function to determine which cognitive faculties are more or less affected, and how this relates to changes on brain scans. This will be related to neuropathology.