This page contains a document that reviews some of the recent literature about chronic pain and the effects that it has on a person. Click on the title of this document if you would like to download a copy of it.
This summary and observation of recent research related to chronic pain is intended to broaden the reader's perspective of the effects that chronic pain has on some individuals. Physicians, physical therapist, and other healthcare providers generally agree that in the event of a soft tissue injury most people experience significant healing of that injury within 6 to 8 weeks. There are a few people who for a variety of reasons do not follow this pattern of recovery from an injury. They may heal more slowly or their injury may become chronic. The U.S. National Center for Health Statistics defines chronic as a condition that lasts three months or more. This article is intended to illustrate that in situations where an injury becomes chronic and where there is a significant element of pain that there is more to pain than just pain.
Brains are Physical
"Brains run the world." (Amen, 2008) Everything that we know, do, and feel originates in and is managed by our brain. We cannot experience anything, or think anything or do anything outside of or separate from the brain. Yet we have no direct internal experience of our brains even existing. We tend to experience an abstract I or a personal me somewhere inside of that space behind our eyes and between our ears, but we have no awareness of the incredibly complex combination of processes that are constantly occurring to manage and control everything in our bodies. According to Dr. Amen, because of this lack of awareness of our own brain, we do not intervene or adapt appropriately when something in our brain is out of balance.
The brain has the ability to reorganize itself by forming new neural connections throughout your life. This Neuroplasticity allows the nerve cells in the brain to adjust their structure and their function in response to new situations or to changes in their environment. (Stiles, 2000). This plasticity is the biological foundation of how all learning and all change take place. More than just thoughts and behavior are changed by this process. "It is apparent that stress can alter plasticity in the nervous system, particularly in the limbic system." (Sapolsky, 2003) The limbic system is where emotions are generated and are first processed. If the physical structure of the limbic system is changed by stress, then the pattern and the influence of emotions themselves are likely to be altered by stress, especially by the stress of chronic pain.
Internal vs. External Awareness
The brain is in a constant state of change. Not only is the physical structure of the brain being altered by the process of Neuroplasticity, there are constant fluctuations in the levels of blood sugar, oxygen, water (dehydration), temperature, etc. that exert effects on how the brain functions. There are also a multitude of neurotransmitters which are continually changing. If the neurotransmitters are too far out of balance, then a person is said to have a chemical imbalance. All of these variables are constantly fluctuating inside of our head, but we do not have any tangible sign that tells us what is going on. Since we cannot directly sense these variables or visually see them we tend to look for things that are happening in the rest of our body and outside of our body to explain what we are experiencing. Ever since the French philosopher Descartes said, "I think therefore I Am." we tend to believe that all we do inside of our head is think and occasionally have feeling. Our beliefs or our "stories" that explain what is happening to us and how it is happening to us will tend to be inaccurate because they do not integrate the events outside our head with the processes that are going on inside of our brain. One negative effect of this tendency to explain everything as originating outside of our head is that the remedy or the adjustment that we used to resolve a problem situation will only take care of the external part of the problem, and it will never address what is happening inside of our brain.
Loss of Brain Tissue
A seminal study using brain imaging techniques found that after adjusting for age and for gender that chronic back pain patients lost about 5%-11% of gray matter a year which is compared to the normal loss of about 0.5% of gray matter a year (Apkarian, et al., 2004). This study by Apkarian which used structural magnetic resonance imaging (MRI) showed that people with chronic pain had a loss of brain tissue which was about the same as 10 to 20 years of normal aging. They found that the more years someone has chronic back pain, the more brain loss they suffered.
Cognitive Impairment and Emotional Suffering
In a study that looked at how chronic back pain affects the emotional centers of the brain it was found that chronic back pain…“engages the emotional-mentalizing region of the brain into a state of continued negative emotions (suffering) regarding the self…” (Baliki, et al., 2006). Another research study found that chronic pain disrupts attention and that this disruption can lead to significant functional impairment and decreased quality of life (Dick & Rashiq, 2007).
Impaired Balance of Function
A later study showed that people with chronic pain had a characteristic pattern of disruption in brain functioning where separate functional areas of the brain quit taking turns in the normal adaptive fashion (Baliki, Geha, Apkarian, & Chialvo, 2008). In the brain that is functioning normally when one area of the brain is called upon to perform a specific function, other areas of the brain quiet down and wait their turn while the first area performs its task (Default-Mode Network Dynamics). The study that was published by Baliki, et al in 2008 showed that for people who have chronic pain the areas in the brain which pay attention to and process the perception and the meaning of pain are overly active and do not quiet down when another area of the brain is called upon to perform a function. The areas of the brain that process pain are always active, and they disrupt and interfere with the other areas when they need to perform their function.
All of these factors alter the normal pattern of brain activity in people who have chronic pain and appear to be manifest in a variety of ways such as: impaired concentration, difficulty learning new information, trouble remembering simple things, increased and unrelenting anxiety, difficulty sleeping, a feeling of impending doom, a sense of separateness and isolation from other people, and feeling like they are losing their mind because they cannot identify an observable reason for what they are experiencing. It is common for people who have chronic pain to lose their entire train of thought and to not be able to continue with what they were saying if they are interrupted while they are talking. As the paragraph above that is labeled Internal vs. External Awareness described, a person with chronic pain will explain what is happening to them largely in terms of their physical pain. This natural inclination to attribute everything that is going on in your life to pain and to other factors outside of the brain and to not take into consideration internal neurological and chemical changes tends to restrict the types of adaptations and adjustments that an individual will try. One aspect of psychological treatment for people who have chronic pain is to help them to understand more about chronic pain and the effects that it is having on them.
Depression as an Adaptation
There is a school of thought in psychology and in psychiatry called Evolutionary Psychology, or Evolutionary Psychiatry that sees the process of depression as a natural response to environmental situations that serves several adaptive functions instead of seeing depression as a disease or an illness. One of these adaptive functions of depression is when an individual or a group is consistently blocked from being able to reach a goal that is important to them; depression helps them to disengage from an unobtainable goal (Nesse, 2000). In the case of chronic pain, this adaptive function of giving up an unobtainable goal helps to protect an injured person from causing themselves further physical damage and increased physical pain by repeatedly doing something that injures them. For our ancestors who might have lived in a cave, the passivity of depression might have helped them to be dormant and to conserve energy by having no motivation and just sitting idle through a long hard winter.
Negative Side Effects
However, in the structure of our society today the adaptive function of depression can be overshadowed by a collection of negative side effects of depression such as: (1) irritable mood, (2) loss of interest or pleasure in activities, (3) sudden change in weight (4) inability to sleep or sleeping too much, (5) agitation or restlessness, (6) constant fatigue or loss of energy, (7) frequent feelings of worthlessness or inappropriate guilt, (8) difficulty concentrating, or (9) thoughts of suicide. It is these negative manifestations of depression that we used to diagnose it as a mental disorder. In today's society depression is rarely ever constructive or adaptive.
Rank Theory: Loss of Self-esteem
According to the evolutionary perspective a second adaptive function of depression is to facilitate a response to losing at something and to promote accommodation to the fact that one has lost (Stevens & Price, 2000). This second adaptive function of depression is referred to as Rank Theory. According to Stevens & Price, depression provides a twofold benefit: “first, it ensures that the yielder truly yields and does not attempt to make a comeback, and, second, the yielder reassures the winner that yielding has truly taken place, so that the conflict ends, with no further damage to the yielder.” In a more primitive society where the leader is the strongest individual this adaptation of rank reduction allows a dominant leader to remain with the group after he is old or injured instead of being killed or cast out. Retaining dominant elders might preserve knowledge and wisdom that is useful to the group.
Negative Side Effects
This process of rank reduction has the serious negative side effect of a deep and painful loss of one's self-esteem. In our society today, this reduction in rank and this loss of self-esteem is more debilitating than it is adaptive, especially for an injured worker. This feeling of being worthless extends beyond vocational activities and can also be manifest in every area of a person’s life such as with friends, with family and with hobbies and activities that previously were enjoyable. While this process of rank reduction is damaging to any individual, it is especially destructive for a person who comes from a class conscious cultural background. This loss of self-esteem and reduction of rank causes a class oriented person to fall below the level of all classes. They become a nonperson and tend to be passively avoided by former friends.
Depression as a Signal for Help
The behavioral expression that accompanies the processes of giving up a goal and of rank reduction is non-consciously signaled to the people around the individual with the result that these people are likely to treat the depressed person differently. Early in the process of a person being depressed this behavioral "signal for help" is likely to pull supportive behavior from people around the depressed person. As time goes on and the person remains depressed despite the supportive efforts of others, those people start to pull away from the depressed person and to start to treat them with disrespect, with disdain, or as if they are invisible. If the process of depression goes this far, then not only does the depressed person feel worthless, the people around them start to treat them as if they are worthless.
Chronic Pain as an Emotion
More than just the cognitive patterns of the brain are altered by chronic pain. Changes in the limbic system can cause significant and far-reaching alterations in the pattern of an individual's emotions (Neugebauer, Li, Bird, & Han, 2004). Because pain signals a potential threat to the well-being of an individual, the area of the emotional system that regulates emotions of fear and anger (amygdala) tends to be overly active when there is chronic pain (Fu & Neugebauer, 2008). This sensitivity or constant monitoring for pain puts the individual in a quasi state of fear that has been labeled "pain fear". This pain fear frequently generates a high level of anxiety. Commonly, depression and anxiety are familiar companions for an individual who has chronic pain. A person with depression and anxiety that are secondary to chronic pain generally cannot account for or explain where their depression or their anxiety comes from because of how they originate deep inside the brain and not from observable events around them. When a person with chronic pain cannot justify the existence of their depression or their anxiety from observable outside events, they feel even further isolated from people around them and from themselves.
Pain Emotion Inside Your Head
This change to an individual's emotional patterning that is secondary to chronic pain results in a qualitative difference in how pain is experienced. Close observation of people who have chronic pain points out that pain changes from being experienced as a sensation in the periphery of the body to being experienced like an emotion that is central to one's being; an emotion that is similar to fear and that is accompanied by considerable anxiety. Pain that is experienced in the periphery can be resisted or fought by paying attention to something that distracts you from it, by ignoring it, or by masking it with muscle tension. Pain that is experienced as an emotion that is similar to fear permeates and alters all other emotions; it shapes one's perception, attitudes and beliefs; and it has disruptive effects on most all of an individual's cognitive activity. Oftentimes they do not feel like they are the same person that they used to be.
A person who has chronic pain is frequently overwhelmed by the combined influence of the emotional aspects of pain and the physical sensations of pain. Because the emotional aspects of pain originate in several different areas inside of the brain and because we cannot pinpoint internal brain feelings people are not able to identify and to label these as two separate feelings. Consequently, they experience and they label everything as physical pain. Narcotic medications ease the physical pain, but they are not very effective in treating the emotional aspects of pain. Antidepressant, anti-seizure, and other medications are more effective in treating the emotional aspect of chronic pain. If these two different types of distress are not understood, then the person who is treated only with narcotics tends to want more and more narcotic medication because the emotional distress of pain is not resolved by narcotic medication, and that emotional distress remains high. Effective treatment of the emotional aspect of chronic pain with the correct medication facilitates the control the physical sensation of pain with much smaller amounts of narcotic medication. The management of the appropriate combination of medications for the emotional effects of pain and the physical sensations of pain requires a physician who understands that the two sensations have different origins, and they usually respond better to different categories of medications.
Exercise Treats Depression
Exercise has been shown to have a positive effect on depression (Otto, Church, Craft, Greer, Smits, & Trivedi, 2007). If depression is an adaptation to unobtainable goals or to insurmountable obstacles, then it appears that exercise is the biological off switch that can counter depression and can bring a person out of it. Most treatment programs for chronic pain have a significant exercise component involved in the program. If a person can tolerate the exercise without an increase in their pain, then they might experience a reduction in their depression and in their anxiety. Also their chronic pain might be reduced as a consequence of increased physical fitness.
Fear of Movement
However, for many people with chronic pain even moderate exercise leads to a significant increase in their pain which sets off a pain fear reaction that results in them becoming phobic towards movement and exercise. Their fear of movement can spread throughout the body as it is associated with movements that result in pain. This fear of movement can extend to the person's posture. A person with chronic pain can develop a strange posture and odd patterns of moving as their body unconsciously tries to avoid postural patterns that are painful. Sadly, those individuals who are afraid of exercise because it increases their pain are not able to achieve a reduction in depression through the use of exercise. They decondition more; they become more depressed; and they become further entrenched in the pattern of chronic pain.
People with chronic pain also generally experience a reflexive process of muscle tension where the body tries to immobilize or to splint the painful area. This process of bracing or guarding can lead to damage to the surrounding muscles in the form of "trigger points". Trigger points are painful, knotted muscles. This automatic defensive process can spread trigger points around the painful area in a manner in which the trigger points appear to be moving or migrating around the body. As pain starts to spread into new areas of the body, a person can become more fearful, more anxious and more depressed.
Concrete Thinking and Manual Labor
A person who tends to think in concrete, black and white manner has a more difficult time adjusting to physical injury and disability. If a person does not have much education and has done manual labor starting at an early age, then they are not likely to have any other vocational skills to fall back upon. Frequently their simplified way of thinking inhibits their ability to use abstract thinking to revise their goals and to restructure the meaning of their life. If a person found meaning in their labor and if they were proud of their ability, then they are likely to suffer a serious loss of self-esteem when they are not able to return to their work. A concrete thinking person who has done manual labor all of their life is likely to suffer many if not all of the effects that have been previously described above. If a person like this has chronic pain, they are likely to show a pattern of emotional decompensation and decreasing adjustment as time goes on. It is easy to mistakenly label this type of person as malingering or as being lazy if you do not look at all of the circumstances surrounding their life situation.
Treatment Resistant Depression
Chronic pain is not just a physical sensation of pain. Many people who have chronic pain are not lazy; many are not malingering; and many are not avoiding a real effort to improve. Chronic pain alters the structure and the function of the brain itself. Chronic pain can function like an emotion and can biologically lead to depression and anxiety that are frequently resistant to medications and other forms of treatment. Unless the conditions that cause the chronic pain are altered, the secondary conditions which are mediated by structural changes in the brain will continue to exert their effects on the individual; they will become self-perpetuating; and they will consume the life of the individual. When chronic pain persists over an extended period of time, it frequently precipitates a depression that is resistant to treatment; and if the chronic pain and the depression continued unabated too long, the depression can also become life-threatening because of the loss of hope and because of how the person is consumed by the feelings of isolation, desperation, and inadequacy.
Suffering is All in Your Head
The depressed person with chronic pain frequently displays what appears to people around them to be frantic, exaggerated descriptions and explanations of their pain and their depression. A person with chronic pain frequently does not have clear and tangible physical, damage to the body that is sufficient enough to account for the degree of pain that they experience. It can seem to others that they are trying to convince people that their distress is real and that it is not just "in their head". When the depressed person's behavior appears exaggerated, then people around them pull away from them in the way that was described above under depression as a signal for help. Much of what they are suffering is not from the pain itself, but it is from the functional and the structural changes that have taken place throughout the brain.
Treatment is Curative
When we see that chronic pain influences and rewires the brain from the emotions in the limbic system up through all of the conscious cognitive functions, it changes our perspective of how chronic pain influences every aspect of a person’s life. Depression and anxiety are not just a matter of having a bad attitude, a weak will, or incorrect thinking. They are a central feature or effect of how the brain has been biologically restructured. It also reshapes our understanding from a psychological perspective of why treatment for depression and anxiety can take so much time and progresses so slowly. Psychological treatment for depression that is associated with chronic pain is not just palliative, but this type of treatment can be essential in helping the person to follow through with other behaviors and activities that will help them to improve such as exercise, continuation of medication, and vocational retraining.
Slow Treatment Moves Forward
The structural changes that occur in the brain of a person who has chronic pain frequently causes treatment for depression and for anxiety to be extremely slow. There are commonly setbacks in the progression of treatment where the depressed person with chronic pain feels that their whole life is coming apart. When they have intrusive anxiety and difficulty sleeping, their ability to function is even further compromised. These individuals with long-term chronic pain are at risk for the pain to spread to other areas of the body because the muscle tension which is meant as a short-term defense against pain results in trigger points and more pain. The concept of rank reduction that is accomplished by extreme lowering of an individual's self-esteem helps us to see that a person with chronic pain can feel so inadequate and worthless that they do not see any meaning in their life or any hope for change. Improvement in depression and anxiety is even more difficult when there is some form of compensation or litigation involved in the overall situation that the individual is coping with because the adversarial nature of the situation keeps a person in a state of alert or alarm. In the case of an accident and an injury there are more layers of complication that inhibit an individual's improvement.
Psychological Treatment is Important
They are at risk for their entire lives to become so consumed by the experience of pain and restricted ability that has started to function as an emotion that most of their relationships and other areas of their lives are destroyed. People pull away from them; they become isolated; and they are at risk for suicide. For someone who suffers from chronic pain, psychological treatment has far-reaching consequences on nearly all areas of their lives. Psychological treatment should be considered for anyone with chronic pain who shows the signs of distress that are described above, and treatment should not be denied or discontinued because the depressed person improves or progresses slowly.
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