Unravelling The Behavioural And Brain Mechanisms Of Compulsive Disorders, And New Ways To Treat Them
Funder
National Health and Medical Research Council
Funding Amount
$635,076.00
Summary
Disorders of compulsion, such as obsessive-compulsive disorder and substance use disorder, are chronic, debilitating, and present a significant cost to the individual and to society. Together, these disorders affect more than 10% of the population. Moreover, 40-60% of these individuals are resistant to current treatment. The current project is aimed at improving the preclinical research underlying our understanding the behavioural and brain mechanisms of such disorders and how to treat them.
Inhibition Of Fear Memories By Extinction: Neural Substrates.
Funder
National Health and Medical Research Council
Funding Amount
$234,250.00
Summary
Anxiety disorders [e.g., Post Traumatic Stress Disorder (PTSD)] are the most prevalent type of psychopathology in the industrialised world. They are associated with characteristic behavioural (e.g., heightened startle) and autonomic (e.g., cardiovascular) reactions. These disorders are often characterised as an inability to regulate the emotion of fear. Significant progress has been made in understanding the neural and cellular processes involved in the establishment of fear memories, but relati ....Anxiety disorders [e.g., Post Traumatic Stress Disorder (PTSD)] are the most prevalent type of psychopathology in the industrialised world. They are associated with characteristic behavioural (e.g., heightened startle) and autonomic (e.g., cardiovascular) reactions. These disorders are often characterised as an inability to regulate the emotion of fear. Significant progress has been made in understanding the neural and cellular processes involved in the establishment of fear memories, but relatively little is known about the mechanisms by which fear memories can be inhibited or suppressed. Understanding this latter process is a key to the development of effective treatments for anxiety disorders such as PTSD where the patient suffers from persistent, intrusive, unwanted trauma memories. A common experimental procedure for reducing learned fear is to repeatedly expose the subject to a fear-eliciting stimulus but without any aversive outcome. This procedure leads to a progressive loss, or extinction, of the fear reactions elicited by the stimulus. Historically, the extinction of fear was thought to be due to an erasure of the fear memory. However, recent evidence shows that extinction inhibits, rather than erases, the fear memory. Because the fear memories remain intact, some structure(s) in the brain must inhibit activity in the fear pathway. This project uses extinction of conditioned fear reactions in rat subjects to determine the structure(s) in the brain that inhibit fear memories and their behavioural and cardiovascular expression. It brings together the expertise of four well-established researchers and uses a combination of behavioural, physiological, immunohistochemical, tract tracing, and lesion approaches to achieve this aim. The proposed experiments will reveal the structure(s) in the brain that control the inhibition of fear, as well as the site(s) of this inhibition in the fear pathwayRead moreRead less
Neuronal Substrate Of Choice In The Rat Whisker System
Funder
National Health and Medical Research Council
Funding Amount
$405,851.00
Summary
Humans and other animals can optimise their goal-directed behaviour by linking stimuli or actions to consequent positive and negative rewards. How does an animal generate such associations, and make decisions in the natural environment where the associations are often uncertain, at times contradictory, and continuously changing? This project uses rat whisker system as an animal model to identify the neuronal basis of perceptual decision making and the role of context.
The Role Of The Orbitofrontal Cortex In Disorders Of Response Inhibition
Funder
National Health and Medical Research Council
Funding Amount
$515,488.00
Summary
We will investigate the role of the orbitofrontal cortex (OFC) in decision-making, particularly the effect of hyperactivity in the medial vs. ventrolateral orbitofrontal cortex on decision-making. Hyperactivity in these structures has been linked to obsessive compulsive disorder and, in line with the distinct functions of the different regions of OFC, we develop and test a novel hypothesis as to the psychological and neural bases of the obsessions and compulsions distinctive to that disorder.
The Role Of Corticothalamic Feedback On The Response Dynamics Of Thalamic Neurons
Funder
National Health and Medical Research Council
Funding Amount
$351,852.00
Summary
A fundamental question in neuroscience is how the brain selectively processes sensory information to generate a reliable representation of the world. Positioned in the centre of the brain, the thalamus plays a key role in sensory processing. This project investigates how the interaction between thalamus and cortex shapes the selection and gating of sensory information. This is a fundamental question in basic neuroscience with the potential to increase our knowledge about attentional deficits.