The Crux of Chronic Pain
Master’s Thesis Philosophy
Universiteit van Amsterdam
Lot Hulshof
Student number: 6057802
Date of defence: 13 August 2014
Supervisor: dr. Julian Kiverstein
Second Reader: dr. Stefan van Geelen
Contents
Acknowledgements
... 3
Introduction
... 5
A medical point of view...12
Phenomenology of the body and the ill body ...26
A phenomenological approach of pain...41
A phenomenological approach to chronic pain...52
Conclusion...62
Acknowledgements
I would like to thank Julian Kiverstein for reading my chapters a thousand times, introducing me to a lot of very interesting literature and having long conversations about how my chapters needed radical changes, which undoubtedly is still the case. I would also like to thank Mattijs Alsem for inspiring me to write this thesis and providing me with a lot of relevant information. Although it wasn’t easy to write about this subject, I still think it’s very interesting. I would also like to thank Mattijs and my friends for not getting mad at me for making them listen to my endless complaints about writing this thesis. Lastly I would like to thank my parents for always supporting me and showing interest in everything that I do.
Introduction
Unless you are suffering from a very rare syndrome, you have experienced what it is like to be in pain. Pain is one of the most common features of life. Unfortunately, pain is more common for some people than to others. People, who suffer from chronic pain, are in pain every day with no prospect of the pain ever going away completely. Because physicians cannot find a physical cause for their pain, chronic pain is very difficult to treat. With all the amazing modern science we have today, physicians are not able to cure these patients completely. Although pain is so very common, the medical knowledge of pain is limited. Also philosophers struggle with this puzzle. Why is pain such a complicated problem? Intuitively, it doesn’t seem that difficult to explain pain. The every day concept of pain is pain as the result of physical damage; when I cut my finger, my flesh will be damaged and this hurts. So pain can be described as a form of perception: I sense damage that is done to my body as pain. However, explaining pain isn’t this simple because there are many circumstances in which pain doesn’t work this way. Firstly, physical damage won’t always hurt. Some people can’t feel pain and some people can’t feel anything at all. Also completely healthy people can damage themselves and only start to feel it later, like when you were so preoccupied doing something that you ‘forgot’ to feel pain. Secondly, pain doesn’t always need to be painful. In some rare cases, patients claim they can feel pain, but it doesn’t hurt. These patients suffer from asymbolia1. Like normal people, they do feel pain as a sensation that is different from tickles, itches and touch; the only difference is that it doesn’t hurt. Thirdly, pain doesn’t need to be connected to any physical damage, like in the case of chronic pain. This is the exception on the every day concept of pain I want to focus on in this thesis. These are the cases of people who feel pain like any other person would, but seemingly without a cause and the pain won’t go away in time. How this can be possible remains a mystery until this day.
So how do we explain these cases? Can we say these people are wrong about their pain? Since pain is a personal experience, it is very strange to tell these people they are mistaken about what they feel. Pain is the feeling of pain. So someone is in pain, when someone feels pain. If someone says he or she is in pain, you can either take at his or her word, or claim that he or she is lying. If there is no reason to believe that someone is lying, it is common to assume that when someone claims he or she is in pain, the person is indeed in pain. Of course there are signs that clearly indicate that somebody is in pain. Based on these signs other people may be able to imagine in how much pain someone is. However, the actual experience of pain is reserved for the person experiencing it. A lot of philosophers have tried to solve the pain puzzle from different angles. Some theories try to map out how the subjective experience of pain is connected to an objective cause of the pain. These theories explain pain as a function. Other theories try to find an essential characteristic of pain and define pain on the basis of this characteristic. These theories try to define pain as a sensation. However, for most of these theories there is a firm counterargument. The philosophical theories that explain pain as a function can’t cover all kinds of pain. As I just stated, in some cases, like in cases of chronic pain, there is no functional relation between the pain and the physical body. Also, theories that are based on one basic characteristic of pain fail to be complete. No characteristic of pain seems to exist in all forms of pain. Even the two main characteristics of pain, the hurt and the physical damage, aren’t necessary conditions for pain to exist, as asymbolia and chronic pain show.2 It is not possible to give a full account of pain by describing it as a function or as a sensation.
Valerie Hardcastle and Nikola Grahek are two philosophers who incorporated medical knowledge into their philosophies of pain. They can explain why other philosophers have been failing in describing pain sufficiently. When we look at a more scientific explanation of pain, the focus is on the brain. How and when we are in pain is dependent on processes in our brain. According to Hardcastle and Grahek, a lot of philosophers have been making the mistake of trying to
understand pain as a simple system, while pain is actually something very complex. There is no pain centre in the brain; the sensation of pain is the result of a lot of different processes in the brain. According to Hardcastle, a lot of philosophers have been mistaken in thinking they can explain pain in terms of only one of these processes3. Therefore these theories will always be incomplete. This is also the reason why pain cannot be defined by one essential characteristic: until now, none of the processes has proven to be essential to pain. This shows how it can be possible to experience pain without the hurt, or to experience pain but not be physically damaged.4
This line of reasoning has led to a broader understanding of pain. Especially for people suffering from chronic pain, these developments have helped. Chronic pain has become accepted as an existing disorder that isn’t necessarily a purely psychological or physical problem. Because pain is recognized as a very complex phenomenon, there are now multidisciplinary treatments for chronic pain.5 Unfortunately these treatments do not always help and chronic pain is still not something curable, but there is progress.
Because physicians are not able to cure chronic pain, the medical treatment of chronic pain is mostly based on helping people to improve their functioning. A common problem for people who suffer from chronic is that they can’t function anymore. They become, for example, unable to work or take proper care of their children. A loss of functionality practically means that patients lose the ability to actively live their life. This loss of functionality is a great part of the suffering that is caused by the pain. Also, the loss of functionality can make the pain worse, as I will explain in the next chapter. Pain causes loss of functionality and loss of functionality causes more pain. A treatment that is focused on improving functionality is therefore at the same time focused on reducing the intensity of the pain. Physicians try to improve their patient’s functioning and lessen the intensity of the pain by changing how patients feel about their pain and training their coping abilities. Physicians do this, inter alia, by talking to their patients
3 Hardcastle 1999, pg 103-104
4 Grahek 2001, pg 70 and Hardcastle 1999, pg 103-104 5 Van Dijk 2013, pg 362
and giving them physical and mental exercises. Since chronic pain is not caused by physical damage, a physician cannot conclude what kind of treatment a chronic pain patient needs by examining the body. Physicians need to find factors in the behavior and beliefs of the patient that have a bad influence on the pain. 6 An example is the experience of getting an injection. The attitude you have towards your body and the pain you expect from the needle can affect the pain of the injections quite rigorously. If you sit down, relax your arm and just let it happen, an injection usually hardly hurts at all. However, if you’re scared of the needle and the pain you might contract your muscles and worsen the pain. In cases of chronic pain, finding out how someone’s attitude is worsening the pain is a bit more complicated. To be able to treat the patient, the physician needs to investigate the whole person. However, it is unclear how physicians investigate a person. Investigating a person is not the same as investigating the psychology of a patient. Although chronic pain is often connected with psychological disorders, chronic pain itself isn’t defined as a psychological disorder. According to physicians, chronic pain is a problem of the mind and the body, or in other words: the person.7 But although the treatment of chronic pain could be described as a treatment of the whole person, it doesn’t become clear from the medical perspective what a person is. Phenomenology can help to clarify this, which is one of the objectives of this thesis. In the first chapter I will discuss the medical perspective from a philosophical point of view.
The treatment of chronic pain shows that physicians acknowledge the complexity of chronic pain. They are not only interested in the physical state of the patient, but they are also interested in the story behind the patient. However, chronic pain is treated and investigated either from a psychological or a medical perspective. Or in other words: the focus is either on the mind or on the body. Therefore some subtle information about how these factors come together is missed. An example may clarify what I mean. Imagine a malfunctioning
6 Verhaak, PFM. Onverklaarde chronische klachten: definitie en omvang. 2004. Uit: Van Dijk, A.J.
red. Chronische pijn en vermoeidheid, bewegingsproblemen en somatoforme stoornissen. De Nederlandse Verening van Revalidatieartsen. Universitair Medisch Centrum St Radboud, 2013. Pg 410-416
7 Van Dijk, A.J. red. Chronische pijn en vermoeidheid, bewegingsproblemen en somatoforme stoornissen. De Nederlandse Verening van Revalidatieartsen. Universitair Medisch Centrum St Radboud, 2013. Pg 373
orchestra. The music they play is awful. There are several ways to investigate what is causing the music to sound so horrible. We could check the functioning of the separate instruments. If nothing is wrong with the instruments, we might see if there is something wrong with the musicians. We may listen to the music selectively, to hear which instrument is failing. When the conclusion of this investigation would be similar to theories about chronic pain, the conclusion would be that all the musicians are causing each other to play off tune. The musicians get confused because of the bad music and therefore start playing badly themselves. They might also start mistreating their instruments, causing the music to sound even more horrible. We now know a lot about what goes wrong with this orchestra. We’ve looked at the musicians, the instruments and how they influence each other. However, we have not really listened to the music itself. By not dividing the music in components, but listening to the music as one piece and describing it as one piece, we discover how the music is out of tune, how it is not in harmony. Instead of only stating that the music sounds awful, we can describe the very nature of the music. We are then able to describe the problem in its totality. I believe that if you want to solve any problem, you will have to look at what the problem is about. You might solve the problem by only looking at its components, but the chance is also great you will miss some important aspects of the problem and therefore never be able to solve it completely. Phenomenology is a philosophical method that can be used to understand chronic pain as something the whole person experiences. In this thesis, I will show what phenomenology is and how important the phenomenological side of the story of chronic pain is.
Phenomenology is a disciplinary field of philosophy developed in the 20th century by Edmund Husserl, Martin Heidegger, Merleau-‐Ponty, Jean-‐Paul Sartre and other philosophers. In this thesis I will follow the views of Husserl and Merleau-‐Ponty. Phenomenology studies the structures of our consciousness. It describes how the world appears to a human being, from the perspective of a human being. Phenomenology explores the conditions that make it possible for us to experience the world as we do. A central aspect of our relation to the world is that it is intentional. This means that we are not just conscious, we are
conscious of something. Our consciousness is directed towards the world. The world is not neutral to us, but instead we make sense of the world. The world is meaningful in our experience. Our consciousness is not something separate from our body; our consciousness is embodied. We understand and act upon the world through our body.8 Phenomenology explores the human embodied experience. I will elaborate on what phenomenology is in the second chapter. Chronic pain is a disorder that exists in the patient’s experience. The treatment of chronic pain shows how the life of a patient is of crucial influence on the pain. As I’ve explained above, when treating chronic pain, a physician is not treating just the body or just the mind; in cases of chronic pain the whole person must be treated. However, the medical perspective does not have the tools to fully understand what it is they are dealing with. I’ve shown that pain cannot be defined as a sensation or as a function. The medical perspective approaches the nature of pain in terms of causes and symptoms. But as I’ve shown in the example with the orchestra: you can’t describe the whole thing by just describing its parts. So you also cannot define pain in terms of aspects and symptoms. The same is true for defining what a person is. Phenomenology can describe what these aspects and symptoms are part of. The disorder of chronic pain is about treating the person in pain. Phenomenology can show what it means to be a person in pain. Phenomenology can thus show what the subject is of the treatment of chronic pain.
In the first two chapters I will discuss the medical perspective on chronic pain and the phenomenology of the body and the ill body. In these two chapters I will argue that the medical perspective is incomplete. In the third chapter I will present the phenomenology of pain. In the last chapter I will attempt to form a phenomenology of chronic pain, based on the medical account of chronic pain. In this thesis I will show how phenomenology can offer a perspective that is complementary to the medical approach to chronic pain. With this thesis I hope to shed light on the crux of chronic pain.
A medical point of view
In this chapter I will attempt to provide a philosophical interpretation of the medical perspective on chronic pain. As I explained in the introduction, chronic pain is a disorder that has no obvious physical causes, but also isn’t defined as a purely psychological disorder. How do physicians understand such a disorder? And does the medical perspective have the conceptual basis capable of fully grasping such a disorder?
Most of the information I’ve used comes from a course on chronic pain for physicians specializing in rehabilitation. Patients are sent to the rehabilitation department when physicians from other departments cannot treat the patients any further, but the patients could still benefit from treatments the rehabilitation department can offer910. At the rehabilitation department, physicians generally don’t try to heal the patient. The goal of rehabilitation is to help the patient to function again in daily life. The course is made out of a selection of articles of quite a wide range of specializations, so the information I’ve used for this chapter does not only include articles from the rehabilitation specialism itself.
Chronic pain in general means pain that lasts for a long time. There are many forms of chronic pain. In this thesis I’ll be discussing chronic pain that has no physical cause. As it is not yet clear what chronic pain is, chronic pain has no somatic definition. Therefore, chronic pain is defined by a group of symptoms that often appear together. The kind of chronic pain I’ll be discussing in this thesis is best described as follows: pain that has lasted for at least six months, is the most striking aspect of the clinical presentation, needs serious clinical attention and leads to distinct functional limitations11. In other words: pain that doesn’t go away (it never stops or keeps coming back) and has a very disturbing effect on the patient’s life, but is not caused by physical damage. In some cases, the pain was once connected to physical damage, but the pain remained after the
10 There are private clinics that also treat chronic pain. A patient suffering from chronic pain therefore
does not necessarily end their search of medical help at the rehabilitation clinic.
physical damage was healed. In other cases, it is a complete mystery what caused or is causing the pain.
Physicians don’t know what causes chronic pain or how to heal it. Unfortunately, however mysterious this problem may be, it is not rare at all. A study showed that 8,6% of people who come to visit their general practitioner have pain complaints with a chronic character.12 There are a lot of different types of chronic pain, of which most share a lot of the same symptoms and are treated in somewhat the same way. I’ll describe some of the most known types of chronic pain.
A common type of chronic pain is fibromyalgia. Fibromyalgia is a form of chronic pain that is very general. Its symptoms are complaints most people have had at some point in their lives. These are complaints like sleeping problems, neck pain, stomach aches and head aches. Patients who suffer from fibromyalgia usually suffer all the time from more of these pains at once.13 The pain can spread over the whole body. Apart from the pain, fibromyalgia patients can also suffer from a wide range of other symptoms, like rashes, hearing impairments, dizziness and depression. Fribromyalgia is often linked to psychological problems, but there needn’t necessarily be a connection. Some people suffer from these kinds of pains without being diagnosed with any psychological disorders. However, this does not mean that the pain has nothing to do with the mind of such a patient. I will elaborate on this point later in this chapter.
Another example of chronic pain is chronic lower back pain. The name implies quite precisely what it is: it is chronic pain in the lower area of the back and sometimes also in the legs. A lot of people suffer from lower back pain problems. However, in 95% of cases of lower back pain no physical problem can be found. Not all of these people actually end up at the rehabilitation clinic. A lot of them just walk around complaining about their back throughout their whole life and just to live it.14
12 Verhaak 2004, Pg 413 13 Van Dijk 2013, Pg 64 14 Van Dijk 2013, pg 88-89
Some cases of chronic pain follow after a trauma. The late whiplash syndrome is a famous example of that. The late whiplash syndrome is a name for a couple of symptoms that can occur after the head is rapidly thrown backwards and forwards (hyperextension-‐hyperflexion) and so distorted the cervical spine. Among other symptoms, patients who have a whiplash can have pain in the neck, back of their head, shoulders and arms, but they can also have complaints like dizziness, nausea and having trouble seeing and hearing. The whiplash syndrome becomes the late whiplash syndrome when the symptoms don’t go away within a few months.15
Another case of chronic pain that is related to a physical trauma is CRPS-‐I (Complex Regional Pain Syndrome type I). We speak of CRPS-‐I when a local part of the body that was damaged doesn’t seem to heal completely. The patient keeps on feeling pain in the body part, although physically the body part has healed. Strangely though, this body part can show a mysterious rash, be swollen or show other physical symptoms. So far it has been completely unclear why the skin reacts like this.16 Although CRPS-‐I is usually described as a chronic pain that is similar to other forms of chronic pain like fibromyalgia, there is still discussion about whether this is correct. Also because there is actually some nerve damage in cases of CRPS-‐II, people wonder whether there is not secretly also some physical problem behind CRPS-‐I that we just haven’t found yet.
There are other forms of chronic pain, but I believe that these four examples already give us sufficient background knowledge to work from. It is notable that they differ in how related they are to physical damage. CRPS-‐I is connected closely to physical damage, since it was triggered by physical damage and is sometimes showing some physical symptoms as well. The whiplash also has a strong relation with physical damage; the neck has had a blow, though it could be that even in the non-‐late whiplash state no physical damage in the neck can be found. Having a bad attitude and sitting too long behind a desk could trigger
15 Van Dijk 2013, pg 92 16 Marinus 2011, pg 101-103
lower back pain. However, in cases of fibromyalgia, a connection with a physical ‘cause’ is hard to find.
It is considered a fact that people suffering from chronic pain are in real pain. However, physicians have a hard time trying to explain to their patients that they suffer from real pain while they can find no obvious physical damage to the body. To make it easier, some physicians explain it to their patients by dividing the body into three parts: hardware, software and mind.17 The hardware is metaphorical for the physical body, the software is metaphorical for the wiring of the brain and the mind is the conscious self. Physicians tell their patients that something went wrong in their software. An example that they can give is the metaphor of the malfunctioning alarm system. Pain is described as an alarm system that is set way too sensitive. The false alarms are considered a ‘software’ problem. The software is in the brain and this is also where the pain actually is, according to physicians. Patients generally have a positive reaction to this explanation.18 Maybe they are glad with this explanation because it sounds plausible and is easy to comprehend. However, this might not be the only reason why patients are generally happy with this explanation. In the next chapter I will elaborate on how this explanation might affect patients and whether I believe this is a good explanation, from a phenomenological point of view.
Unfortunately, although brain research has developed quite rapidly through the last few decades, we still don’t know enough about the brain to be able to just fix this malfunctioning ‘software’. Therefore, the treatment of chronic pain is generally dependent on treating the symptoms of the disorder. When a chronic pain patient is being treated, the physician will investigate if there are any factors in the life of the patient that have a perpetuating effect on the pain. There might be habits in the patient’s life or maybe the patient has thoughts that have a negative effect on the experience of pain and the patient’s functioning. The physician will also help the patient to improve his or her ability to cope with the pain. Because chronic pain is a disorder that is connected to very different aspects of the patient’s life, a whole team of specialists treats a chronic pain
17 Van Dijk 2013, pg 13-14 18 idem
patient. Such a team can consist out of a physiotherapist, a psychologist, an occupational therapist and a rehabilitation physician for example. The rehabilitation physician diagnoses the patient with chronic pain and keeps an overview of the treatment plan.19
The thoughts or habits of a patient, that can have a perpetuating effect on the pain, I will address as ‘perpetuating factors’. Because there is no obvious connection between chronic pain and physical damage, physicians have to look for other explanations of the pain; perpetuating factors. How physicians understand perpetuating factors in relation to the body, can tell us a lot about how they understand chronic pain. However, the medical understanding of chronic pain in terms of perpetuating factors can also show how the medical perspective on chronic pain is limited. I will first present some of the most common perpetuating factors to chronic pain, and then discuss what can be concluded from this information.
It is very important that the patient trusts the diagnosis of the physician. The treatment of chronic pain will not help if a patient keeps on believing that the pain is caused by physical damage although the physician has told him or her otherwise. Refusing to believe that the pain isn’t caused physically is one of the perpetuating factors in chronic pain. A patient who falsely believes the pain is physically caused won’t be motivated to follow the treatment the physician can offer. The treatment of chronic pain consists of physical and psychological exercises, which won’t work if the patient doesn’t actively participate. For example: the physician will try to train the patient to use his or her body counter intuitively. Believing the pain is caused by physical damage affects how the patient uses his or her body. Trying to avoid certain movements can cause the patient to move in a physically unhealthy way, which causes more pain. If the patient doesn’t trust the diagnosis, he or she will probably refuse to use the hurting body part, afraid the exercise might damage it more. Also, unnecessarily avoiding certain movements restricts daily functioning. The very goal of the treatment of chronic pain is to improve the patient’s functioning. This will not
succeed if the patient does not trust the physician and therefore doesn’t actively cooperate. For the treatment to be effective the patient needs to be prepared to make an effort to change his or her way of living.
Another common perpetuating factor is the catastrophizing of pain. People who catastrophize their pain are people who let the pain restrict them more than necessary. They would for example claim that the pain overwhelms them and render them completely unable to do anything. This has a very negative effect on the treatment and it worsens the intensity of the pain experience. 20 Patients who catastrophize their pain have a hard time participating in the treatment, because the treatment involves using your body although it hurts. If the patient claims at the start of the treatment he or she is not capable of doing any of the exercises, the physician won’t be able to help the patient much. The patient therefore has to overcome this catastrophizing of the pain. Saying a patient is catastrophizing pain is not the same as claiming the patient isn’t really in so much pain (although undoubtedly some physicians may mean it like this). Thinking differently about the pain can make a great difference, whether the patient is or isn’t overreacting the intensity of the pain.
What has also proven itself to be a great perpetuating factor for chronic pain is fear of pain. The case of Lotte, a patient suffering from CRPS-‐I, illustrates this quite well. Lotte once broke her leg, but her leg never really restored. She tried to give her leg rest by not using it, but the pain even got worse. Her leg was red, warm, swollen, her nails crumbled off and she suffered from excessive hair growth on her leg. She was able to do less and less. She couldn’t work anymore, had trouble taking care of her children and at one point she couldn’t even put on socks because her leg hurt so much. Because her leg was already showing some strange symptoms, Lotte was afraid that using her leg would make it worse. She was afraid she would damage her leg so badly that it needed to be amputated. Physicians convinced her she should get over her fear and use her leg. At first she didn’t believe she could stand on her leg. She thought she was not afraid but was just being rational. But because nothing else helped to relieve the pain, at some
point she chose to trust the physicians and follow the treatment. They wanted to show her how she could use her leg without damaging it. Slowly the physicians made her use her leg more and more. In the beginning of the exercises she was terribly scared that she would fall, that her leg would break or the skin would fall off. Nothing of the kind happened, but instead she became able to do more things with her leg. When she was finally fully convinced that using the leg would still hurt but wouldn’t damage the leg, things got better for her. Eventually she could even go back to work, which was a great achievement for her since she was a hairdresser and had to stand on her leg all day long.21
The perpetuating factors I just described are examples of how physicians explain that chronic pain is being influenced by biological, psychological and environmental factors. Catastrophizing and fear of pain are examples of psychological factors, the physical effect of unnecessarily avoiding certain movements is an example of a biological factor. Environmental factors indicate influences from the social environment. In the examples I presented, the influences of the social environment aren’t made specific, but that doesn’t mean that environmental influences did not play a part in the development of the chronic pain of the patients in the examples. Negative social environmental influences on the pain are for example a lack of support and negative feedback from other people.
To understand how physicians see these influences in relation to chronic pain, we should look at the theoretical basis underlying the idea of perpetuating factors. Chronic pain is a disorder that is diagnosed on the basic of a group of physical and psychological symptoms. The biomedical model for medical practice, a model that only considers biological factors as relevant for the research and treatment of the body, can therefore not suffice to explain and describe chronic pain. The research and treatment of chronic pain is based on the biopsychosocial model. The biopsychosocial model considers the role of biological, psychological and environmental factors relevant for medical research and treatment. The patient is not seen as a body, but as a person.
21 den Hollander 2006, pg 318-325
However, the biopsychosocial model is very vague about how these factors come together in a person, although this is a core constitutive element of this model. It could be argued that all these factors come together in processes in the brain. However, Lukas van Oudenhove and Stefan Cuypers argue in a philosophical article that analyses the biopsychosocial model, that this does not solve the vagueness of the biopsychosocial model. It may be true that the interaction between bodily functions and the brain can be explained by investigating the brain, but this interaction can thus be fully explained in biological terms. It is the whole point of the biopsychosocial model that the interaction between different factors in the life of a person cannot be described in biological terms. According to Van Oudenhove and Cuypers, the environmental and the psychological factors in the biopsychosocial model, can both be described as influences on the mind, and biological factors can be described as influences on the physical body. They summarize the problem of the biopsychosocial model, by stating that it is about the interaction between body and mind, but misses a concept of the nature of this interaction.22 A neurological explanation of how bodily functions interact cannot explain the interaction between body and mind, because such a distinction does not exist in a neurological explanation. We can therefore conclude that physicians who base their understanding of chronic pain on the biopsychosocial model, and thus speak about a person being influenced by biological, psychological and environmental factors, assume this body-‐mind interaction, but have no concept of what this means. Although treatments of chronic pain that target the perpetuating factors I discussed above proof to be effective to some extent, the concept behind it is incomplete. Phenomenology can provide a different perspective on the body that can fill up this gap, as I will argue in the next chapter.
We can conclude now that the biopsychosocial model cannot explain the interaction between body and mind, but what about the neurological explanation of chronic pain? If the neurological explanation of chronic pain can explain the interaction between bodily functions, why can chronic pain not just be fully explained in neurological and therefore biological terms? If that is the case, there
will be no need for the biopsychosocial model. The following examples of theories about chronic pain are mainly about the biological processes behind chronic pain. The importance of the role of a non-‐biological interpretation of these processes can be derived from these examples.
When an animal is sick, it displays a certain sort of behaviour; it acts tired, down, it doesn’t feel like having sex or other social contact and is more sensitive to pain. This is called sickness behaviour. Sickness behaviour is caused by the immune system, which is activated once the body is infected with some disease or is wounded. This behaviour is quite similar to the behaviour that people suffering from chronic pain show. Apart from physical damage and infections, also stress and pain appear to be able to cause the immune system to activate. The immune system is known to have a good memory; the effectiveness of vaccinations is an example of this. It is theorized that, if the immune system can be activated by stress and pain, the immune system also might be capable of having a memory of stress and pain. When the immune system is repetitively exposed to the same stimuli, it can develop sensitiveness for these stimuli.23 This theory is supported by neurological research. The brain has the capacity to change itself in such a way that it can adapt it abilities to function in a certain environment. A person can for example develop a more sensitive hearing or sense of smell when the person’s circumstances require this. Also, when something has hurt me in the past, I might react sooner and more violent when I feel it again. The immune system is one of the physiological systems that ‘communicates’ with the brain, causing it to adapt. This process is called sensitization.24 Sensitization could thus be seen as a protection mechanism. However, sometimes something goes wrong in this process. The process of pain becoming chronic could be an example of this. The pain loses connection with the initial stimulus and moves to a more ‘central’ place in the body. This central place is the brain.25 Once moved to a ‘central’ place, the pain can keep on developing, although it has lost contact with the original stimulus. As I already described in the introduction, pain is the result
23 van Doornen 2012, pg 156-158 24 Van Dijk 2013, pg 126
of a lot of different activity patterns in the brain26. Neurological research shows that pain consists of, inter alia, emotional, cognitive, sensory, and interoceptive processing. This means that any of these processes can cause chronic pain. It also means that when the pain becomes chronic, it affects all these processes. Therefore, chronic pain leads to more problems than just the problem of being more sensitive to pain. For example: it can cause a person to become emotionally instable and depressed.27 All the affected processes can in turn affect other processes in the brain again, causing the problem to become very complex. This process is called cross-‐sensitization.28. Because of this increasing complexity, chronic pain also becomes increasingly more difficult to treat. It is therefore very important that the treatment of chronic pain starts as soon as possible.
Based on the theory of sensitisation, a treatment is developed that is focused on the undoing the sensitization process of pain. This treatment is called mirror-‐ therapy. In an article about mirror-‐therapy an example is used of a patient who has CRPS-‐I in one of the hands. The patient has to place both hands on a table; the healthy hand in plain sight, the hurting hand behind a mirror. The patient can’t see his or her hurting hand anymore, but instead he or she sees the reflection of the healthy hand in the mirror at the place where their hurting hand should be. The patient then has to move his or her healthy hand, but look at the ‘hurting hand’, which is actually the reflection of the healthy hand. Looking at this reflection should feel like looking at the hurting hand. The idea is that the patient is ‘fooled’ into thinking that moving the hurting hand does not hurt. After some of these exercises, the patient has to move the hurting hand along with the hand in the reflection. It is proven that this treatment can have a positive effect on people suffering from acute CRPS-‐I (people who haven’t been suffering from CRPS-‐I for very long). However, the longer the patient has been suffering from CRPS-‐I the lesser effect the therapy will have. Patients who have had CRPS-‐I for several years didn’t benefit at all from the treatment. In such cases the process of
26 Jensen 2010, pg 21 27 Simons 2014, pg 65 28 Simons 2014, pg 72
sensitization might have developed already too far and therefore cannot be undone anymore. 29
Now what can we conclude from this theory about the conceptual frame the theory of sensitization is based on? Most of the theory is about mapping out a biological system that may explain how pain can become chronic. However, the theory doesn’t only consist out of explaining biological processes in biological terms. There’s quite a lot of psychology involved as well. The term chronic pain still refers to a group of physical and psychological symptoms. Sickness behaviour, depression and being emotionally unstable are all psychological descriptions. The biological processes in the theory are explained as related to psychological phenomena. These psychological phenomena cannot be reduced to biological processes because this would mean the loss of a lot of information. The relation between factors in the life of a person and the biological processes is essential for figuring out what has caused these biological processes. The relevance of perpetuating factors to chronic pain is an example of this. Mirror therapy is said to be a therapy that influences mental imaging.30 This means that the mental image someone has of the execution of a certain action influences the experience of executing that action. We could say that such a mental image can work as a perpetuating factor to chronic pain. The effectiveness of treatments of chronic pain that target perpetuating factors to chronic pain, like mirror-‐therapy, should show enough to be able to back up the idea that chronic pain shouldn’t be solely explained in biological terms. However, the question remains what the conceptual basis is of how the biological and psychological factors come together. What is for example the nature of a mental image?
The lack of a conceptual basis of how all the factors come together leads to another problem with the biopsychosocial model. Although it seems clear that the biopsychosocial model is not meant to be dualistic, this model does not exclude a dualistic approach to the body. The biopsychosocial model takes the person as the centre of the model. In the person, all the biological, psychological and environmental influences should come together. But the theory doesn’t
29 Alderliesten-Visser 2007, pg 368-371 30 Alderliesten-Visser 2007, pg 369-370
