Determining the effects of monoaminergic regulation of frontostriatal systems in different aspects of impulsive decision-making.

Impulsivity is a characteristic of human behaviour that can be both beneficial and detrimental in our everyday lives. An impulsive decision can allow us to seize a valuable opportunity, or to make an ill-considered choice that we live to regret. High levels of impulsivity are not only considered socially unacceptable, but they are a key symptom in a range of psychiatric illnesses including bipolar disorder, attention-deficit hyperactivity disorder (ADHD), pathological gambling, personality disorders and substance abuse. Understanding the neurobiological basis of impulsivity could provide valuable insight into these afflictions and potentially lead to the development of new treatment and therapeutic approaches. Dr. Catharine Winstanley is exploring the role of different regions of the brain on aspects of impulsive decision-making and gambling. One of the most commonly-used measurements of impulsive decision-making in human volunteers is the Iowa Gambling Task (IGT), in which subjects try to accumulate points by choosing from options associated with varying net gains or losses. Winstanley successfully developed a model of the IGT for use in rats, allowing her to measure their cognitive processes. She is also determining whether changing levels of brain chemicals, such as dopamine and serotonin, can affect impulsive choice, and whether these chemicals activate similar molecular pathways in neurons that can alter brain function and behaviour.