An Impirical Investigation Of Psychosis Proneness In Amphetamine Users: Current And Predictive Validity
Funder
National Health and Medical Research Council
Funding Amount
$462,750.00
Summary
The use of amphetamines has increased in Australia in the last decade. According to the 1998 National Household Survey, lifetime use of amphetamines has increased by over 50% from approximately 6% in 1995 to approximately 9% in 1998; recent use (last 12 months) has increased from 2% in 1995 to approximately 4% in 1998. This increase appears to be even greater in Queensland, the site of the proposed study, which has seen both an overall increase in the use of illicit drugs and an increase in the ....The use of amphetamines has increased in Australia in the last decade. According to the 1998 National Household Survey, lifetime use of amphetamines has increased by over 50% from approximately 6% in 1995 to approximately 9% in 1998; recent use (last 12 months) has increased from 2% in 1995 to approximately 4% in 1998. This increase appears to be even greater in Queensland, the site of the proposed study, which has seen both an overall increase in the use of illicit drugs and an increase in the use of amphetamines specifically. The most recent estimate of the number of current users (use within the last 12months) aged 14 years and over in Queensland is 85.5000. This compares to 17.000 recent heroin users in the same age range. Of particular concern is the increase in the use of methamphetamine, which has high abuse potential producing euphoric effects that are similar to, but longer lasting than, those of cocaine. Also of concern, given the increasing purity and availablity of methamphetamine, is the link between amphetamine use and psychosis, a psychotic disorder characterised by sensory hallucinations, paranoid delusions and a loosening of associations. Despite this well established link, there are surprisingly few studies in which the course and onset of amphetamine psychosis has been studied. In this reseach the relationship between subclinical features of psychosis, measures of psychosis proneness and other factors implicated in the development of schizophrenia will be investigated in a prospective cohort in which amphetamine users will be followed up once per month for twelve months.Read moreRead less
I am a neuroscientist, studying fundamental mechanisms related to addiction. A major feature of my research is the neuropharmacological characterisation of potential novel therapeutic strategies to combat drug-seeking behaviour.
Reducing The Key Alcohol And Other Drug Related Harms In Australia
Funder
National Health and Medical Research Council
Funding Amount
$782,370.00
Summary
I am a leading alcohol and other drug researcher with an established national and international reputation for high quality research and translation. Over the next five years I will tackle the three key issues in the alcohol and other drug field: injecting drug use, methamphetamine use and harms and high risk drinking by young people, by developing, implementing and testing new interventions.
Neuropathways And Synaptic Adaptations Underlying Drug Addiction In Central Dopamine Systems
Funder
National Health and Medical Research Council
Funding Amount
$184,812.00
Summary
There is a rising trend in addiction to drugs, such as opioids (heroin) and stimulants (methamphetamine and ecstasy). A key feature of this addiction is intensified craving for the drug with repeated use. A major brain component thought to mediate drug-craving is the dopamine (DA) neurotransmitter system, consisting of cells in the midbrain that project nerve terminals to forebrain structures involved in reward-based learning. DA cells undergo long-term depression (LTD) and potentiation (LTP) of ....There is a rising trend in addiction to drugs, such as opioids (heroin) and stimulants (methamphetamine and ecstasy). A key feature of this addiction is intensified craving for the drug with repeated use. A major brain component thought to mediate drug-craving is the dopamine (DA) neurotransmitter system, consisting of cells in the midbrain that project nerve terminals to forebrain structures involved in reward-based learning. DA cells undergo long-term depression (LTD) and potentiation (LTP) of synaptic strength when excitatory inputs to DA cells are stimulated. These findings are important to drug addiction as amphetamine has been shown to block LTD and enhance LTP in brain slices of DA cells. Thus, changes in LTD and LTP by illicit drugs may underlie the conditions necessary for expression of drug-induced behavioural sensitisation, the best-accepted model of drug-craving in human addiction. To date, these studies have all been conducted in brain slices. Therefore, the functional importance of this synaptic plasticity in midbrain DA cells has yet to be shown in terms of changes in DA release in forebrain terminals in the living animal. For the first time we will address this issue by recording DA cell firing activity together with DA release using a newly developed technique that permits DA release to be monitored in the living brain in 'real-time' (100,000 samples-sec). This will allow us to identify the origin (cortical excitatory inputs) and receptor mechanisms that mediate LTP and LTD in DA cells and their effects on DA release. Recording DA cell activity with real-time measurement of DA release will promote a new cutting-edge technology to the Australian Neurosciences. These data will provide 'first of its kind' evidence of the functional anatomy and receptor mechanisms underlying synaptic plasticity in DA neurons associated with repeated drug use and ultimately enhance our basic understanding of the neural mechanisms of human drug addiction.Read moreRead less
Serotonergic Mechanisms Underlying Impulsivity And Vulnerability For Stimulant Addiction
Funder
National Health and Medical Research Council
Funding Amount
$336,318.00
Summary
There is increasing evidence to suggest that impulsivity, a personality trait associated with an increased tendency for premature actions, may predispose individuals to stimulant addiction. The current study employs a non-invasive brain imaging technique in rats – positron emission tomography (PET) – to investigate the implicated role of serotonin (5HT) in impulsivity thereby providing potentially new insights into neural vulnerability mechanisms underlying stimulant addiction.
Brain Pathways Underlying Vulnerability To Drug Relapse
Funder
National Health and Medical Research Council
Funding Amount
$416,788.00
Summary
Addiction to drugs is a major health and social burden for Australian society. Once addiction is established, prevention of relapse is the most significant obstacle to successful treatment. Unfortunately, efficacious pharmaceutical options to treat relapse are lacking. By employing an animal model of relapse that accurately reflects drug taking in humans the proposed project aims to advance our understanding of the brain mechanism underlying addiction.
A Phase III Randomised Placebo-controlled Trial Of Mirtazapine As A Pharmacotherapy For Methamphetamine (Ice) Dependence
Funder
National Health and Medical Research Council
Funding Amount
$3,923,009.00
Summary
Crystalline methamphetamine ('ice') is a growing concern in Australia. There are no approved medications that can be used to treat dependence on this drug. This clinical trial will examine whether mirtazapine, a newly identified treatment agent for methamphetamine use, can be used safely and effectively in routine clinical care to manage methamphetamine dependence in Australia.
Mephedrone (Meow, 4-Methylmethcathinone): Examining The Effects Of A Novel Party Drug On Brain And Behaviour
Funder
National Health and Medical Research Council
Funding Amount
$399,796.00
Summary
Mephedrone ("Meow") is a novel recreational drug that has rapidly increased in popularity in recent years. Users report that mephedrone has the stimulant-like qualities of cocaine, combined with the prosocial effects of MDMA. Anecdotal and case study reports indicate that mephedrone may have the potential to engender compulsive patterns of use as well as toxicity in overdose. The current project will use animal models to assess how mephedrone affects the brain and behaviour and to assess its add ....Mephedrone ("Meow") is a novel recreational drug that has rapidly increased in popularity in recent years. Users report that mephedrone has the stimulant-like qualities of cocaine, combined with the prosocial effects of MDMA. Anecdotal and case study reports indicate that mephedrone may have the potential to engender compulsive patterns of use as well as toxicity in overdose. The current project will use animal models to assess how mephedrone affects the brain and behaviour and to assess its addictive potential.Read moreRead less
Cognitive Phenotyping And Personalised Treatment For Methamphetamine Addiction
Funder
National Health and Medical Research Council
Funding Amount
$483,402.00
Summary
Prevention and treatment of addiction to stimulants such as methamphetamine is imperative for community health and safety. This fellowship will enable me to apply my expertise in impulsivity and addiction to identify people at risk of increasing methamphetamine use and to develop and evaluate cognitive training therapies that will empower people with methamphetamine related problems to control their drug use. Outcomes include a risk identification and triage tool and three novel therapies.