Professor Trevor Robbins, Cambridge University
Hannah - we now bury our heads into the next level of understanding of ADHD – so genes and the environment. Back to Trevor Robbins for this…
Trevor - At a genetic level, there's also some evidence for the involvement of these chemical messengers because some of the genes that have been linked to ADHD which turns out to be a very highly heritable condition are implicating dopamine and noradrenaline mechanisms. But this is not to say that we think ADHD is purely a genetic condition. Of course, it isn’t.
There are very strong environmental determinants and this might be the diet. They might be things like lead poisoning or some toxins in the environment which affects your brain development early on, or it may be psychological. So, there's some evidence that levels of ADHD are greater in those Romanian children who were brought up in horrible adoption homes. Their level of ADHD-like behaviour is much higher in some of those children, suggesting that social deprivation may also play a role in some sense.
So, those are the main levels I would suggest by which we can understand ADHD – the psychiatric or the clinical level, the psychological level, the brain level, the neuroscience level, and the genetic and causation level.
Hannah - Thank you, Professor Trevor Robbins from Cambridge University. And perhaps these genes could also be used to help provide markers for ADHD diagnosis in the future.