Drugs and medicines: what do they do in your brain?
What are the effects of medicines and drugs on our brain and behaviour? This is the central question of the public symposium ‘Drugs and the brain’ taking place on 26 October in the Leiden Mare Church.
The symposium is an initiative of the LIBC (Leiden Institute for Brain and Cognition). This year the institute has chosen as its research theme ‘Pharma’, a project led by LIBC director Professor Serge Rombouts and Professor of Cognitive Psychology Sander Nieuwenhuis. The neuropsychopharmaceutical research they carry out is twofold: they investigate the neural basis of behaviour and they study the effect of substances such as ketamine, morphine, dopamine, alcohol and cannabis on the functioning of the brain.
Nieuwenhuis focuses in his research on the influence of the noradrenaline system – ‘the most wide-spread neurotransmitter system’ – on our cognition. He is especially interested in the ‘switching’ that people are capable of: between being focused and being open to new influences from outside. ‘We know that people with ADHD and PTSS (post-traumatic stress disorder) have a defective neurotransmitter system. But we have to find out more about the fundamental underlying mechanisms before we can really understand these diseases.’ Nieuwenhuis is now developing methods for this, and investigating the effects. For instance he looks at whether healthy people who are prescribed a noradrenergic drug (a kind of anti-depressant which heightens the activity of this neurotransmitter system) become more explorative.
Nieuwenhuis studies people’s behaviour. Rombouts puts them in a scanner and investigates what happens in their brain after they have been administered a dug or medicine. ‘This kind of research is necessary because we can see that certain substances impact behaviour, but we often do not know exactly what happens,’ he explains. ‘In addition, different substances may have the same effect on the outside, but in your head they may activate very different mechanisms. This is due to the fact that there can be very different interactions between the different kinds of brain networks.’ If you know exactly what each substance does in the brain, the most suitable medicines can be used, for instance against dementia, depression, anxiety or schizophrenia.
Rombouts: ‘Once we have relevant substances which influence the important neurotransmitter systems, for instance for dementia, we might be able to detect early dementia even before a person’s behaviour starts to show signs of dementia: on the basis of reactions in his brain. In the brain we might be able to see earlier and with more precision what is wrong.’ This might help in reaching a diagnosis, and possibly also in finding a treatment, he says. Rombouts also wants to investigate the working of anti-depressives in this way. He hopes that this will make it possible to determine more quickly than is currently the case which substances in which dosage might help. ‘At present, it’s a question of trying something and waiting for weeks.’ This might also speed up the development of medicines.
(16 oktober 2012 / Malou van Hintum)
Health across the human cycle is one of the six profile themes of research at Leiden University.