Guide Voice: What goes on in the minds of
children, how they play, learn and develop, has always been
fascinating to observe.
While behaviour differs from child to child, in most cases it is
easy to understand. But there are some 150,000 in the UK alone who
suffer severely from Attention Deficit Hyperactivity Disorder and
their behaviour is harder to handle and can badly disrupt their
lives.
Researchers at King's College London's Institute of Psychiatry
have been studying what goes on in the brains of children with
ADHD.
SOT: Professor Taylor, Institute of Psychiatry, King's
College London - "It is a substantial problem
because what it interferes with is not only interfering with
learning in school but it interferes with your personal
relationships and your home life as well. Because if you do have
ADHD, people think you're not paying attention to them, they don't
like it, it becomes very aversive and people react negatively to
you. And we think that something of the order of one and a half
percent of children have got a severe problem that really need
intervention."
Guide Voice: The researchers have been using
functional Magnetic Resonance Imaging or fMRI to compare brain
activity between children with ADHD and those without it.
fMRI allows them to build up accurate images of activity within
the brain in a painless and completely non-invasive way.
In the first study of children with ADHD who have never been on
medication for their condition, which could itself have altered
brain activity or brain architecture, the researchers discovered
that ADHD sufferers had less activity in certain regions of the
brains compared to people without the condition.
SOT: Dr Katya Rubia, Institute of Psychiatry, King's
College London - "What we do is we put them in
the scanner for an hour and they have to do several computer tests
which mimic the behavioural problems they have. And then we look at
areas which do activate differently in ADHD children compared to
normal, while they're doing these computer tests. And what we then
find is that children with ADHD show a different activation from
normal children. And they show under-activation in certain areas,
so they don't activate as much as normal children, which is
probably the cause for the problems they have because they can't
activate certain areas of their brain."
Guide Voice: The children were asked to hold
back or stop doing things during the scans, and the abnormalities
shown on the scans occurred in the right frontal lobe of the brain.
The right side of the brain is normally involved in inhibiting
tasks, acting as a brake on activity, and the children with ADHD
showed less activity in this area than those without it.
SOT: Professor Taylor, Institute of Psychiatry, King's
College London - "What the latest tests are doing
is that they're showing that children that have it aren't just idle
or stupid, they're showing that there is a part of the brain that
is not only too small but it's also under-active. So the
over-active person is going with an under-active brain and the part
of the brain that is under-active is the part that is normally used
in self-control and concentration. So it show what the physiology
of the problem is."
Guide Voice: The results show that what is less
active in children with ADHD is part of an 'attention network'
activated by people without the disorder, which grows and becomes
more active as a child gets older but has not developed so quickly,
in children with ADHD.
Dr Katya Rubia - "We're also looking
at how specific the abnormality is, we're looking at other
disorders, children with conduct disorder, children with autism,
with depression and with obsessive compulsive disorder, in order to
understand whether they have different or the same frontal lobe
abnormalities, and what we've found so far is that other children
with other disorders show different abnormalities in different
frontal lobe areas than children with ADHD. So what we've found is
relatively specific to ADHD."
Guide Voice: Identifying the precise areas of
the brain affected will greatly assist in finding ways to treat
ADHD, and also show sufferers that there is a specific
physiological cause for their problems.
SOT: Professor Taylor - "The immediate
hope that it's offering is that the disorder is becoming better
understood. When we know the physiology of anything in medicine,
that is absolutely the first step towards developing the medical
treatments. So the immediate thing for people to understand is that
the disorder is now being better understood in brain terms. The
genetic research is coming along very excitingly as well so we're
moving towards a state where the scientific understanding of the
disorder will lead to better help for it."
ENDS
