Editor’s note: On January 31, 2019, the Cognitive and Affective Neuroscience of Pain (CANoP) Special Interest Group of the Swiss Society for Pain Research (the local IASP chapter) held its inaugural meeting in Fribourg, Switzerland. In this interview, the meeting’s scientific committee, including Petra Schweinhardt, Balgrist University Hospital and the University of Zurich, Switzerland; Chantal Martin Sölch, University of Fribourg, Switzerland; and Chantal Berna, University of Lausanne, Switzerland, spoke with Mayron Piccolo, a PhD candidate at the University of Fribourg, to discuss CANoP as well as some of the latest ideas in the field. Below is an edited transcript of their conversation.
What is the main goal of CANoP?
Petra Schweinhardt (PS): We want to bring together people who work on the topic of cognitive and affective neuroscience of pain in Switzerland, and create a network for them to interact. We had the suspicion there would be quite a few labs interested in this topic.
Chantal Martin Sölch (MS): One goal is also to stimulate research in this field because we have the impression that it is growing, and now we can really learn from each other, and be more efficient in networking and knowing who is doing what. Also, we wanted to link research with practice; that’s why we also had medical doctors, psychologists, and nurses attend the meeting. CANoP presented recent research, with elements translating to clinical practice.
Chantal Berna (CB): I was also very pleased with the number of students who attended, and how they were very involved and curious. The poster session was lively, and the students were impressively open to discuss and interact with this Swiss community of researchers.
What is the current status of the field of cognitive and affective neuroscience—how far along is it?
PS: We already know quite a bit, especially from research over the last couple of decades. We’ve learned a lot about the interactions among emotion, cognition, nociception, and pain perception, favored by the advent of brain imaging. One of the next steps is to understand how all of these processes contribute to the phenotype of patients and their clinical problems—for me, it is almost a holy grail to be able to decipher that.
MS: What I really liked about the CANoP meeting is that we also had social neuroscientists, who take a completely different approach; this is an advance for the field. And there are now efforts to translate research into treatment. We are also preparing a project on the effects of a mindfulness-based psychological intervention to treat pain symptoms and restore the neural responses to reward. There are also many efforts to assess the construct of the questionnaires that are used to understand pain physiological processes, and to understand exactly what we are measuring when we use these scales in clinical practice.
CB: Positron emission tomography (PET) and spectroscopy are also very exciting, but this methodology still has to develop so that we can become better at understanding the phenomena rather than just describing them.
There’s a lot of interest in brain imaging in relation to pain. How do you foresee the progress of pain brain imaging over the next few years?
PS: That’s a very difficult question. There is no doubt that there will be progress, but we are always going to be limited in what we can do in humans in terms of how invasive we can be. What is very exciting is that there seems to be increasing interest amongst pain researchers who study animals in moving up the neuraxis to study supraspinal circuitry, including emotional circuity, cognitive aspects, and trying to combine that with behavioral testing in animals. This can be relatively sophisticated—rats are smart fellows! So I find that very exciting; our field can benefit a lot from this.
MS: This is very interesting because in human research, it’s exactly the opposite, where people are moving down the spinal cord. Christian Büchel talked at CANoP about the development of methodology to image the spinal cord. So we human researchers are going down, and the animal researchers are going up; at some point in time, we might meet somewhere.
One of the topics discussed at the CANoP meeting was reward processing and its relationship with chronic pain. Can you say a little bit about that?
MS: I have been investigating reward processes in different mental conditions. I came to pain from that side of the research because I was working on depression, which is highly associated with pain, and pain is very often associated with depression. For me, it was very interesting to see the interaction between pain and reward because it’s an interaction between two basic systems at a neurobiological level. I would soon find out that all the articles that I had been reading on pain and reward were papers written by Petra!
At the time, we were looking at the dopamine response to rewarding stimuli and saw aberrant responses in people with depression; there was overactivity in response to those stimuli. This is not what we expected. It will be interesting to see how reward processes may be altered in the setting of chronic pain, which of course is different from that of depression.
Hypnosis was another interesting theme of CANoP. Chantal, as someone who works in this area, can you discuss that a bit?
CB: I was really interested to listen to Mike Brügger’s talk at CANoP; he is taking a fundamental approach to understanding hypnosis as a cognitive process through a large, very systematic project. It is combining different methodologies, including fMRI and EEG, to study the hypnotic state in 50 healthy volunteers. The state induced by hypnosis and its underlying neural circuitry are a central debate in the field. I think that Mike’s work on healthy volunteers will teach us a lot.
Hypnosis is a very interesting approach because it can modulate the way people think and the way they perceive sensations. It seems to be a good tool to use in patients with chronic pain who are deficient in their reward mechanisms. This is because we can induce rewards through imagination, whether a new pleasant experience or a pleasant memory. We can also work on mental imagery of motor activities and bring back the idea and pleasure of movement—cycling, dancing, or swimming, for instance—while maybe still suffering from fear of movement, as many people with chronic pain do. So through imagination, we can work on different pathological processes that have been described in chronic pain, and that’s very powerful.
PS: I’m very curious, Chantal, about hypnosis with regard to pain. Do people try to do things like have the patient imagine that they can visualize their pain and then try to make it shrink or be put away into a box or something like that?
CB: Yes, that’s a very classic approach: visualizing pain, and working on a metaphor for it—perhaps it’s a thing, a color, a shape or smell, and then we try to transform it. Another classic way to work with people who have pain is to use the imagination to apply the perfect anti-nociceptive treatment such as lidocaine—that’s the anesthetic glove metaphor. If they manage to feel their hand turning numb, then they often transfer that to the painful body part.
We have built up a lot of wisdom in the clinic on treating pain with complementary techniques, whether with hypnosis, mental imagery, or mindfulness approaches. It’s fascinating that the scientific community is now starting to examine and validate these techniques. I find it quite wonderful.
To learn more about the CANoP Special Interest Group, please visit the SIG’s web page on the Swiss Association for the Study of Pain (SGSS) website. To join SGSS, visit here.
Image credit: Norbert Aepli/Wikimedia Commons. Creative Commons Attribution 2.5 Generic license.