The Extinction Of Conditioned Fear And Its Implications For Cue Exposure Therapy
Funder
National Health and Medical Research Council
Funding Amount
$322,430.00
Summary
This project studies extinction of Pavlovian conditioned fear reactions in rats. Extinction of these reactions is an animal model for exposure therapy used in the treatment of anxiety disorders in people. In exposure therapy, the patient, aided by the clinician, confronts trauma-related cues in the absence of any overt danger. The intention of this therapy is to reduce the ability of the trauma-related cues to provoke the fear reactions that are undermining the patient's quality of life. In Pavl ....This project studies extinction of Pavlovian conditioned fear reactions in rats. Extinction of these reactions is an animal model for exposure therapy used in the treatment of anxiety disorders in people. In exposure therapy, the patient, aided by the clinician, confronts trauma-related cues in the absence of any overt danger. The intention of this therapy is to reduce the ability of the trauma-related cues to provoke the fear reactions that are undermining the patient's quality of life. In Pavlovian conditioning, subjects (typically rats) are exposed to a signaling relation between an initially neutral stimulus (e.g., a noise) and a feared outcome (e.g., foot shock). When later repeatedly exposed to the initially neutral but now feared stimulus (the noise) in the absence of the feared outcome, the fear reactions it acquired progressively decline until eventually it fails to elicit any such reactions. The fear reactions are said to have been extinguished. There has been significant progress in understanding the psychological processes and neural mechanisms underlying the acquisition of fear reactions, but much less is known about the processes and mechanisms underlying the extinction of these reactions. The project has two general objectives. The first is to determine the conditions of extinction training that promote long-term loss of fear reactions. The second objective is to determine how the brain controls this extinction of learned fear. Achieving these aims will be significant for two reasons. First, it will contribute to understanding the mechanisms by which animals (including people) learn to adjust their behaviour to bring it into line with the current relations that exist between events in the world. Second, it will provide important information about how such adjustment is facilitated or impaired across extinction training and, thereby, contribute towards understanding both the successes and failures of cue exposure therapy for fear-related disorders.Read moreRead less
Fear Relapse: Neural Substrates Underlying Its Inhibition And Prevention
Funder
National Health and Medical Research Council
Funding Amount
$437,476.00
Summary
Exposure-based therapies are effective for anxiety disorders such as post traumatic stress, but two challenges remain: 1) patients that have learned to inhibit their fear are likely to relapse, requiring further therapy; 2) many drop out of therapy since it is aversive and anxiety provoking. We use an animal model to: 1) identify the neural substrates underlying fear inhibition; and 2) determine the conditions that prevent relapse and encourage participation in treatment.
The Effect Of Oxytocin On The Formation, Expression And Inhibition Of Fear Memories
Funder
National Health and Medical Research Council
Funding Amount
$390,243.00
Summary
Oxytocin is a hormone peptide which reduces amygdala activation to threatening stimuli and reduces anxiety in people and laboratory rodents. These results suggest that oxytocin could be a valuable pharmacological adjunct to exposure-based therapy for anxiety disorders. However, several questions must be answered before its therapeutic potential can be determined. As such, this project examines the effects of oxytocin on fear-related behaviours in rats, and neural fear circuits in the amygdala.
A Randomised Trial Of The Augmentation Of Cognitive Behaviour Therapy With Fluoxetine For Anxious School Refusing Youth
Funder
National Health and Medical Research Council
Funding Amount
$539,191.00
Summary
School refusing youth consistently suffer from anxiety and sometimes depression. They become severely emotionally distressed when taken to school and experience social and academic difficulties in the short and long term as well as psychiatric illness in adulthood. Our program investigates whether treatment can be improved by enhancing psychotherapy (cognitive behaviour therapy) which helps over half of anxious school refusing children, with antidepressant-anxiety medication compared to placebo.
Using Epidemiology To Inform Psychiatric Classification (DSM-V And ICD-11)
Funder
National Health and Medical Research Council
Funding Amount
$631,502.00
Summary
Classification systems are vital for scientific progress. The classifications of mental disorders of the World Health Organization and the American Psychiatric Association are both being revised and this Australian team is a principal contributor to both processes. We have access to three national epidemiological surveys (n-30,000) that will inform fundamental issues by developing models of mental disorder typology and identifying practical improvements in the classification systems.
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
Pubertal Transitions In Mental Health And Behaviour: The PHASE-A Study Of Social Roleand Lifestyle Transitions
Funder
National Health and Medical Research Council
Funding Amount
$1,656,785.00
Summary
Over the past four decades problems such as depression, anxiety, self-harm and substance abuse have increased in young people. Recent research indicates that puberty is a time when these problems commonly first emerge. This five-year study of 4000 students will examine a question of whether social transitions that are too soon (e.g. early initiation of sex) or problematic (e.g. bullying from peers) may explain the increase in these health problems as children pass through puberty.
Neurobiological Causes Of Overeating In A Rodent Model - Hedonic Versus Homeostatic Control
Funder
National Health and Medical Research Council
Funding Amount
$431,215.00
Summary
Unlimited access to palatable high fat foods, in conjunction with a sedentary life style, has led to increased obesity. Exactly what mechanisms drive over consumption of energy rich foods and override mechanisms that normally regulate body weight? This project will examine feeding behaviour in rats fed palatable high fat diet, to examine when and how they eat. The contribution of brain chemicals implicated in addiction to this eating, and the impact of withdrawal of food will be examined.
Danger Ideation Reduction Therapy For Obsessive-Compulsive Checkers: A Randomised Controlled Trial
Funder
National Health and Medical Research Council
Funding Amount
$156,447.00
Summary
Obsessive-compulsive disorder (OCD) is a psychiatric disorder that affects up to 3% of the general population. People with the disorder experience unpleasant intrusive thoughts that they find distressing and have a strong urge to perform particular behaviours. Fears about fire and burglary are common and excessive checking of electrical appliances and locks can take many hours a day. Checkers represent one of the largest OCD sub-groups. Because of the time-consuming nature of the condition, soci ....Obsessive-compulsive disorder (OCD) is a psychiatric disorder that affects up to 3% of the general population. People with the disorder experience unpleasant intrusive thoughts that they find distressing and have a strong urge to perform particular behaviours. Fears about fire and burglary are common and excessive checking of electrical appliances and locks can take many hours a day. Checkers represent one of the largest OCD sub-groups. Because of the time-consuming nature of the condition, social and occupational functioning is often severely restricted. Many sufferers will also experience extreme social isolation and depression. The World Health Organisation ranks this disorder as 20th among all causes of burden of disease. The development of effective interventions could substantially reduce the economic and social burden of this disabling anxiety disorder. The aim of this project is: (1) to compare the therapeutic efficacy of a new treatment approach (Danger Ideation Reduction Therapy) with that of Exposure and Response Prevention (ERP); It is hypothesised that: (1) subjects who receive 12 sessions of DIRT will show greater post-treatment and follow-up reductions in symptomatology than subjects who receive ERP.Read moreRead less
Evaluation Of Internet-based, Cognitive Behaviour Therapy For The Treatment Of Anxiety Disorders In Adolescents
Funder
National Health and Medical Research Council
Funding Amount
$570,750.00
Summary
Anxiety disorders affect around 5-10% of adolescents and are associated with a range of adverse consequences if left untreated. The majority of young people with anxiety disorders do not seek nor receive treatment. This may be due partly to the perceived stigma of attending a mental health clinic and logistic problems of attending therapy. A challenge is to identify ways in which treatment can be made more accessible to adolescents in need, particularly those in rural and remote areas. Contrary ....Anxiety disorders affect around 5-10% of adolescents and are associated with a range of adverse consequences if left untreated. The majority of young people with anxiety disorders do not seek nor receive treatment. This may be due partly to the perceived stigma of attending a mental health clinic and logistic problems of attending therapy. A challenge is to identify ways in which treatment can be made more accessible to adolescents in need, particularly those in rural and remote areas. Contrary to original beliefs, evidence shows that the internet can be used to deliver effective psychological therapies for a range of mental health problems, including anxiety disorders. So far this research has focused on adults, but adolescents may be in a particularly strong position to benefit from these forms of therapy, being experienced users of internet resources. This research investigates the effectiveness of internet-based cognitive-behaviour therapy (CBT) in the treatment for anxiety disorders in adolescents. Recently we have piloted CBT for anxious children that combines clinic and internet therapy, with half the therapy sessions in the clinic and half over the internet. Pilot data show that clinic + internet therapy produced significant reductions in anxiety and is almost as effective full clinic-based therapy. The proposed research builds on our pilot work by evaluating the effectiveness of a more extensive internet-based therapy in which all sessions are completed using the internet and with an older age group. The research also examines the factors that predict which young people will respond most positively to the intervention so that the treatment can be matched to those most likely to benefit from it in the future. The aim is to develop an effective internet-based treatment for adolescents with anxiety disorders that is easily accessed and suitable for use in rural and remote populations, requiring minimal face-to-face therapist contact.Read moreRead less