Learning in an MRI scanner

Arachnophobia and mild depressive or psychotic symptoms occur most often between the ages of 16 and 26. During this period, the brain is still developing, which often helps therapy to be successful. “Many people didn’t receive any treatment for their symptoms at that age, and that makes them very good candidates for our SmartScan research,” says the professor. Once the subject is screened and found to be suitable, he or she spends three consecutive days in an MRI scanner. By having the subject perform simple learning tasks, the researchers can identify which brain areas are active during which emotional reaction. “For motor functions, that's usually already known down to the brain cell level, but for emotions it’s not so exact. We believe that the symptoms developed during a learning process and that treatment is also a learning process, but in reverse. We capture that process in the scanner.” After this, most subjects undergo a form of treatment, and about ten weeks later they again spend three days in a row in the scanner. In addition, the subjects fill in all kinds of questionnaires, and they are also asked to record their activities, state of mind, etc. a few times a day at home using an app.

Safe circle

In the scanner, people are not shown any images of spiders. But they are shown a large circle which stands for ‘safe’ and a small circle which stands for ‘unsafe’. “Then we also show all sizes of circles that are in between. For someone who’s very astute, everything in between can be easily distinguished as safe, because they know that only the small one is unsafe. But someone who is naturally more anxious will react more sensitively to stimuli that are similar to what is unsafe. That’s what determines the avoidance behaviours that people have in everyday life. For example, if someone is afraid of a spider they’ve seen in a corner of the garage, they will not only avoid that particular garage, but also all situations which seem similar. Similar things are also unsafe. And the more that happens, the more limited they are. We want to know what happens in the brain because it may have a predictive value for the future of the symptoms. It says something about the degree to which something is rooted in the brain.” A few years ago, the researchers conducted a study of arachnophobia, in which it was shown that the overactivity of certain brain areas in these people could be lessened with therapy. The stronger this effect, the less scared people still were of spiders eight years after the research.

Eeeuuuw!

The reason why many people are so afraid of spiders is not really known. “It’s the number one of all phobias. One theory is that it’s been imprinted on us from our ancestors that spiders are dangerous, while in this part of the world that hasn’t been the case for a long time. What I think definitely plays a role is that they’re difficult to control. They move quickly and unpredictably. And besides fear, they instil a sense of disgust. If you ask a room of people to create a sound that’s appropriate for when you see a spider, you hear something like ‘Eeeuuuw!’ or ‘Eeek!’. We have more female subjects in the group. Whether that’s because guys really are less afraid or they’re just not supposed to shy away from things, is very difficult to research.”

Subjects are still being added to the study until the end of January and only after that can all of the research data really be analysed. However, it has already been shown in the control group (the ‘symptom-free’ subjects) that the more capable people are of distinguishing between images that seem very similar, the less generalisation of fear they exhibit. In other words, imagine you’re mugged in a dark parking garage by a man with a beard and a hoodie. If you encounter another man on the street with a beard and a hoodie, you can either clearly distinguish that it’s someone else (and you feel less anxious), or you lump all men with beards and hoodies into a group and feel very anxious.”  In the latter case, life feels very dangerous and you go out less often. That type of generalisation is very important in the daily lives of people with anxiety and trauma symptoms. It determines how incapacitated they are. Take for instance people with post-traumatic stress disorder after they’ve worked in a war zone. We investigate the functioning and change in areas of the brain in people with milder symptoms, but ultimately we also want to apply the knowledge to these target groups with more severe symptoms.”

CV Koen Schruers

Prof. Koen Schruers is a professor of Mechanisms of Affective Disorders, psychiatrist at Maastricht UMC+ and head of the Academic Anxiety Center (Academisch Angstcentrum), a cooperation between UM and Mondrian that has been going on for 25 years. As a researcher, he is primarily interested in the underlying mechanisms of affective disorders, such as anxiety and obsessive-compulsive disorders, as well as in the development and treatment of them.