Neurocognitive knowledge offers hope for anxiety disorders
Anxiety is a common condition experienced by millions of people. It can lead to the avoidance of challenging situations, missing out on experiences, and becoming socially isolated. “When it comes to anxiety disorders, clinical analysis has tended to focus on how people think and feel,” says DARE2APPROACH project coordinator Karin Roelofs from Radboud University in the Netherlands. “The thing is, you can feel anxious, but as long as this doesn’t stop you from carrying out specific actions, then it is not really a disorder. We know of so many high-performing people that experience anxiety, are perhaps scared to death of going on stage, but they do it.”
Scanning neural mechanisms
In the DARE2APPROACH project, which was funded by the European Research Council, Roelofs took a neurocognitive approach to better understanding why avoidance behaviour persists even if it comes at such a huge cost. To do this, she looked at the brain mechanisms that enable people to override automatic avoidance tendencies and examined how we weight the costs and benefits when deciding to approach or avoid a situation. The project team tested neural mechanisms using a range of techniques. For example, they scanned the brains of people who took ‘approach and avoid’ actions to obtain a reward at the risk of getting a shock or seeing an angry face using a joystick. “People tend to avoid shocks and angry faces, even if avoidance comes at a cost,” explains Roelofs. “So, what is going on in the brain that helps us to override this impulse?”
Neuroscientific approach to avoidance behaviour
As expected, people with anxiety disorders displayed greater difficulty than ‘healthy’ people in overriding their automatic avoidance tendencies. What made this project so groundbreaking was that it was able to reveal the neural mechanisms underlying this difficulty. “Conventional thinking has been that the front part of the brain (the prefrontal cortex) displays reduced activity in people with anxiety disorder,” notes Roelofs. “What we found however is the exact opposite – it is overexcited. This is what causes the dysfunction.” The project team also looked at various chemical and structural components of the brain and found that the amygdala – a major processing centre for emotions – sends strong signals to the prefrontal cortex. “We really took a neurocomputational approach to this challenge,” says Roelofs.
Treating people with anxiety disorders
With this new understanding, the project looked at how treatment of people with anxiety disorders might be improved. A novel technique – called dual site transcranial alternating stimulation – was developed for this purpose. “We found that slow wave activity from one part of the brain synchronises with fast waves coming from another part when a patient approaches an angry face,” remarks Roelofs. “Our thinking was if we could better control this synchronisation, we might be able to improve reactions to difficult situations.” The project team found that stimulating brainwaves in two neural areas could improve synchronicity and emotion control in both healthy and anxious individuals. A clinic is now testing the intervention to boost exposure therapy for anxiety patients. In addition to the clinical implications, Roelofs believes that the project’s findings have strong implications for future research. “We should invest in finding ways to directly intervene with the core neural system, for instance using transcranial ultrasound stimulation to directly modulate activity including in the amygdala,” she adds. “This is something I am working on now.”
Keywords
DARE2APPROACH, neurocognitive, anxiety, brain, clinical, neural
