Interview with Rudi de Raedt, PhD

How did you first get involved in the NTTR SIG?

I’ve been coming to ABCT since 2006 and that’s where I met Greg Siegle as well as other SIG member such as Thilo (Deckersbach), Jan (Mohlman), Becca (Price), and Kristen (Ellerd). At that time, the idea that neuroscience could be important in the development of therapeutic techniques was not well understood by many people.

When I met Greg, he was already working on the idea of neurocognitive therapies and it was immediately clear that our vision was similar. I had just published an article (De Raedt, 2006), “Does neuroscience hold promise for the further development of behavior therapy?” It was not easy to publish it in a psychology or psychiatry journal, as many people see the neurobiological approach to affective disorders or clinical work as a narrowing or reductionism. On the contrary, I have always found just the opposite. In this approach we not only look at the level of symptoms, behavior and cognitions, but also at the level of information processing styles underlying psychopathology and the related biological processes. It’s just another level of measurement that brings us a more integrated view on problems and helps to expand our knowledge. Many studies have already shown that this neurocognitive perspective can be useful in the development of new treatments.

How did you come to this realization yourself?

I started studying psychology at 29 because I was interested in the neurobiology of cognitions, emotions and behavior. I started my career as a sculptor and psychology was a hobby while I was working, I guess it went a bit out of hand! Science is also a great way to be creative.

After obtaining my PhD, in 2001 I was lucky to get a position at Ghent University, where I was free to start my own research line in experimental psychopathology. I wanted to adopt a straightforward experimental approach combining insights from clinical psychology, cognitive psychology and neuroscience. If you want to investigate the causal relationship between brain processes and information processing, you need to be able to manipulate these mechanisms and therefore in 2003, I started using neurostimulation techniques. We manipulated DLPFC activity and looked at the effects on attentional biases for emotional and non-emotional information.

At the start, we were mainly interested in neurostimulation as an experimental tool but evermore neurostimulation is used as an intervention and we now received a large grant to combine neurostimulation with cognitive training. We have observed cognitive control decreases with the number of depressive episodes and there seems to be a “scar” in depressed patients. Logically, you might try to remediate the brain by trying to change neuroplasticity in these areas, which due to the scarring of depressive episodes, now function differently.

We have found that the scar may be at the level of attentional processing and cognitive control, as people are not able anymore to disengage from negative stimuli or inhibit rumination. Therapy trying to change cognitions or cognitive restructuring may require intact frontal functioning; therefore “therapy resistant” patients may need combination of techniques, including biological techniques, to improve.

For example, we observed post-synaptic serotonin 2A receptor sensitivity is decreased in therapy resistant depressed patients. Ten sessions of rTMS seem to “reboot” the system and resensitize the receptors. But why would you hope all symptoms would disappear only by using neurostimulation? So we may want to “reboot” the system with stimulation first and then try training, therapy, or medication.

I compare it to when someone gets a new hip, you still have to learn how to move and walk with the new hip. I think it’s exactly the same with depressed patients, we can intervene at the brain level but people may also need to learn to behave differently. Recently in my lab, we found cognitive training, DLPFC training that Greg (Siegle) developed, decreases rumination. However, my colleagues also observed that positive emotion regulation strategies do not increase. In the future, we may want to combine cognitive training with emotion regulation strategies or other more conventional cognitive behavior therapy approaches. We can combine interventions to give people new possibilities to overcome their disorders and hasten the process.

With other medical problems, a physician looks at symptoms and behaviors as well as biological variables. This is exactly what we should do in psychiatry, measure levels of symptoms, behavior, cognitions, and neurobiological disturbances and look for solutions to act on these.

This sounds very in line with the Research Domain Criteria (RDoC) approach.

One of things I said in my application presentation at Ghent in 2001, my goal was move from symptoms and categories to transdiagnostic processes. But in this approach, it is equally important to look at the constructs (e.g. negative valence system) at all levels of analyses, not only biological (e.g., genetics, molecules and circuitries), but also behavior, cognition, etc. Some colleagues critique RDoC for too much emphasis on neurobiology but when you look at (the RDoC) matrix, there are also non-biological units of analysis specified. The relationship between different processes at all levels helps us to increase our understanding of symptoms and problems. It’s very complex and we are far from a solution but that's also exciting! We try to put pieces of the puzzle together, knowing very well that at each phase it may be a small piece but also keep the larger picture in mind. I always remind my PhD students, they have to know the larger framework in which their studies fit.

What direction would you like to see the SIG take in the next 10 years or so?

SIG members are passionate and enthusiastic about what they do. It is important to have people who dare to be creative and innovative. I believe the development of the neurocognitive approach to therapies will automatically follow the advances of the research of (SIG) members and I’m positive that the SIG will be ever more influential.

The current size of the group is substantial but not too big, which means most members can know each other. The SIG grew organically and the new people who come are really interested. On the other hand, the more people who would like to join, the more power the neurocognitive approach has to inspire. It would be good to involve more colleagues from Europe. I know there is a lot of interest in ABCT as it is a large, excellent conference, and I hope also in Europe there will be increasing interest to integrate neuroscience and Clinical Psychology.