Hyper kids struggle to identify smells

Reduced ability to name smells by children with attention deficit hyperactivity disorder (ADHD) has revealed for the first time a link between an impaired smell processing and the disorder.

The one-year study of 88 children aged 6–16 (44 with ADHD) led by the University of Melbourne and Murdoch Children’s Research Institute shows the children with ADHD had reduced ability to identify odours.

The study involved using scratch and sniff tests of common smells such as orange, chocolate and pizza. It was published in September's Journal of Clinical Psychiatry.

According to the paper’s lead author, Felicity Karsz of the University of Melbourne’s School of Behavioural Sciences and Department of Paediatrics, “right nostril impairment appeared more evident among the children with ADHD”.

According to co-supervisor Professor Warrick Brewer of ORYGEN Youth Health Research Centre – Department of Psychiatry, similar problems of smell identification have been observed in neurodevelopment disorders such as schizophrenia and obsessive compulsive disorder.

“The sense of smell is increasingly becoming a useful way to detect a vulnerability to a neuropsychiatric disorder,” he says.

Prof Brewer says the findings could lead to a smell test which would act as screening tool for children with ADHD but would not replace current treatments.

Co-supervisor Professor Vicki Anderson, from the Murdoch Children’s Research Institute and the Royal Children’s Hospital, says this information could supplement the well-established assessments for ADHD.

“There could be different reasons for exhibiting symptoms of hyperactivity and attention deficit and this area needs a range of strategies to confirm diagnosis and manage treatment,” Prof Anderson says.

(Source: Journal of Clinical Psychiatry: University of Melbourne: October 2008)