6th February 2012

Paul Overton and Tom Stafford awarded Children's Hospital Charity Research Funding

Prof Paul Overton and Dr Tom Stafford, along with members of the Children's Hospital and the Academic Unit of Orthoptics and Ophthalmology, have been awarded £10K by the Children's Hospital Charity Research Fund.

Details of the project are as follows:

Collicular hyper-responsiveness in Attention Deficit Hyperactivity Disorder

Lay summary: Attention deficit hyperactivity disorder - ADHD - is the most common childhood behavioural disorder, although estimates of its prevalence vary widely. A substantial part of that variance arises from the fact that
there is considerable ambiguity in the interpretation of the current diagnostic criteria for the disorder and how they relate to the symptoms observed, which has significant implications for treatment. What is needed is a ‘marker’ for ADHD which would remove some of this diagnostic confusion. Since the early work on ADHD, increased distractibility has been recognised as a core symptom of the disorder. A growing body of evidence suggests that this distractibility is caused by increased sensitivity of a part of the brain which deals with sensory information – the superior colliculus. The superior colliculus, a sensory structure which lies deep within the brain, is particularly sensitive to certain types of visual stimuli, in particular small, moving and peripherally located stimuli. We intend to present such stimuli to ADHD patients using a specialised device used by Optometrists and Orthoptists called a perimeter, and compare the
performance of ADHD patients with age matched control subjects. We anticipate that ADHD patients will be more responsive to such stimuli and that their performance with respect to those stimuli – since it is dependent of the superior colliculus – will provide a much needed biological marker for ADHD. A biomarker for ADHD would help to standardise  and thereby revolutionise the diagnosis of this prevalent and debilitating condition.