Every brain cell helps in understanding ADHD
29 November 2005
Every brain cell helps in understanding neurobiology of ADHD
The holy grail of a diagnostic test for Attention Deficit Hyperactivity Disorder (ADHD) could be discovered through interdisciplinary collaborations set up at a University of Otago conference on the neurobiology of ADHD.
Internationally renowned researchers from Britain, Japan, South Africa and the USA are meeting with an emerging group of researchers from the University of Otago to discuss their research and create new interdisciplinary collaborations to help children suffering from ADHD and related disorders.
“One of the problems with ADHD is that there is no diagnostic test, so all diagnoses are made on the basis of behaviour,” organiser Professor Jeff Wickens, of the Department of Anatomy and Structural Biology, says.
“ADHD is a neurobiological disorder but we don’t understand the underlying neurobiology. We are talking about a complex combination of genes and the environment acting together. There are probably several neurobiological features leading to a similar condition, so its not a simple disorder to understand.”
The aim of the First Dunedin Workshop on the Neurobiology of ADHD is to promote links between researchers working at multiple levels of analysis - from the cellular mechanisms of dopamine through to the behavioural expression of abnormal reward sensitivity in children with ADHD.
Children with ADHD tend to have low levels of the brain chemical dopamine. Dopamine affects mental and emotional functioning and helps regulate concentration, attention and inhibition.
Session topics include genetics, the environment, gene-environment interactions, neurobiology of dopamine and reward dysfunction in children with ADHD.
Among the international researchers are Professor Greg Gerhardt, from the University of Kentucky in the USA, and geneticist Dr Jonathon Mill, from the University of London, Britain.
Prof Gerhardt hopes his work on understanding how neuron repair can potentially be carried out in Parkinson’s patients could also be applied to conditions like ADHD.
“The issue is determining if ADHD is a disease. We are on a quest to find out what is different in the brain and if it can be repaired – not just to treat the disease, but to modify the way the brain functions,” he says.
Dr Mill was part of a team that discovered a clear genetic component to ADHD, with a number of genes linked to the disorder, particularly those connected to dopamine receptors.
Dr Mill says the disorder could be caused by a number of genes interacting combined with environmental factors, for example prenatal exposure to smoking and alcohol.
University of Otago psychology researcher Dr Gail Tripp is director of the ADHD Research Clinic in the Department of Psychology, where children with ADHD are referred by the Dunedin Public Hospital for assessment and diagnosis.
Dr Tripp is involved in a series of studies looking at whether deficits in pragmatic language and social problem-solving skills contribute to the social difficulties of young people with ADHD. She has also been involved in the development a stress management programme for the parents of children with ADHD.
- ADHD is one of the most common behavioral disorders of childhood, estimated to occur in 3% to 7.5% of school-aged children. The disorder is characterised inattention, over-activity and impulsivity that interfere with the child’s behavioral, academic and social functioning. Despite extensive research uncertainty continues to surround the cause and management of this disorder.