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Scans Reveal Brain Changes in ADHD

A review of brain scan studies has determined that ADHD is a real medical condition that requires educational reform, and is not simply a matter of children misbehaving.

Dr Helen Boon of James Cook University analysed 174 MRI studies that compared the brain function of people diagnosed with ADHD against a control group, and found significant anatomical and processing differences in the ADHD group. “The brain circuitry in someone with ADHD is different from someone without – no question,” Boon said.

Among the differences in children with ADHD were reduced volumes in the basal ganglia and thalamus, cerebellar grey matter and cortical grey matter thinning, and white matter connecting regions involved in memory and executive functions such as impulse control, planning, prioritisation and organisation.

Boon said that some teachers and parents didn’t believe ADHD was a genuine condition. “International surveys indicate that many teachers are ambivalent about recognising ADHD as a real disease,” she said. Furthermore, school resources and support staff such as teacher aides are not automatically provided to children with ADHD unless they also have major cognitive impairments or disabilities like autism.

“It is clear that students with ADHD need to have access to special educational provision through the public education system under the Disabilities Act, like others with disabilities such as hearing impairment or autism,” Boon concluded in her review for Educational Evaluation and Policy Analysis.

Boon said that cognitive and behavioural approaches, rather than medication, are the best way to help children with ADHD. “The prefrontal cortex responsible for executive functions like planning, attention, cognitive flexibility and attention setting is one of the last cortical regions to reach its mature thickness in adolescence and is therefore amenable to training... For example, many of the grey matter structural abnormalities found in ADHD with MRI imaging have been shown to be improved or eliminated entirely with cognitive training.

“Some examples of tasks used in the training are labyrinths (planning), word list recall (memory), detecting the missing numbers from numerical lists (attention), creating lists of objects sharing certain characteristics (cognitive flexibility) and code deciphering (problem solving).”