The experience of pain is a complex interaction of biological and psychological processes. The traditional view of pain was that it is the result of damage to tissues of the body that is detected by nerves that transmitted this information to the brain. This biologically focused view is accurate, but it is incomplete. The signals being sent by the nerves can be altered by a number of factors when it comes to pain treatment, including an individual’s psychological state or expectations.
Placebo effect on pain treatment outcomes
One of the most well known examples of expectations influencing the perception of pain is the placebo effect. For centuries, researchers have found that delivering a treatment with no therapeutic benefit (e.g., a sugar pill) would produce pain relief in a substantial percentage of cases. This has been observed not just with oral medications, but also with injections and surgical procedures. Though some might attribute these findings to patients lying either about their initial pain or the relief, or conclude that the researchers had tricked the patient into reporting relief that they weren’t really feeling, other research suggests these explanations do not fit the facts.
Researchers in recent decades have utilized the open-hidden paradigm to study placebo effects. In this research, all patients are given an effective, widely used pain reliever. In the open treatment method, the drug is delivered by a doctor visibly administering the medication to the patient. In the hidden treatment method, a machine administers the medication through the patient’s IV without the patient’s awareness. Patients receiving the drug through the open delivery method reported greater pain relief than those receiving the hidden delivery method. In other words, even a pain treatment that is effective will be less successful when the patient is not expecting the benefit. This suggests that the placebo effect is part of a broader phenomenon. Our expectations, either that we will or won’t get pain relief, influence the results of a pain treatment.
Psychological factors in pain
The implications of this research go beyond those patients involved in research studies. Patients have varying expectations about how effective a pain treatment will be based on a number of factors, including their own experiences with other treatments, what they have heard from others, and their view of the medical profession in general. These expectations can also be influenced by aspects of their psychological state, such as depression or anxiety.
Psychologists who study mood disorders, such as depression and anxiety, have found that they are often sustained by inaccurate beliefs and expectations. For example, a person might believe that their life will always be bad, when a high probability exists that it will get better. Another person might believe with certainty that something very bad will happen, when the probability of that outcome is almost nonexistent. Whether one is experiencing a mood disorder or simply going through a period of depression or anxiety, these states can influence expectations about the effectiveness of treatments for pain.
Numerous studies have found that depressed or anxious patients get less pain relief from injection therapies, implanted devices, and surgical procedures than do non-depressed and non-anxious patients. This is not surprising, given the potential for depression or anxiety to lead to unrealistically pessimistic expectations. This illustrates the importance of obtaining appropriate treatment for mood disturbances in addition to medical therapies for pain.
Our own practice has behavioral health services and a patient support group available for patients. Other forms of psychological counseling are available to patients who feel they may benefit from it. It is worth noting that it is particularly relevant for patients with chronic pain, because receiving treatment for mood disturbances may help not only their mood, but potentially improve their pain relief as well. One additional positive research finding is that when depressed or anxious patients do get effective pain relief from various pain therapies, their depression or anxiety tends to improve as well.
Ted Swing has more than eleven years of research experience in psychology and pain medicine and four years of teaching experience, has published in top psychology and medical journals, and has presented his research at major conferences. He received his Ph.D. in Social Psychology from Iowa State University and has been the Research Director at Arizona Pain since May 2012.