MIND-BODY MEDICINE:
MIND-BODY MEDICINE
Mind-body medicine focuses on the interactions among the brain, mind, body
and behavior, and the powerful ways in which emotional, mental, social,
spiritual and behavioral factors can directly affect health. It regards as
fundamental an approach that respects and enhances each person's capacity for
self-knowledge and self-care, and it emphasizes techniques that are grounded in
this approach.
Definition of Scope of Field
Mind-body medicine typically focuses on intervention strategies that are
thought to promote health, such as relaxation, hypnosis, visual imagery,
meditation, yoga, biofeedback, tai chi, qi gong, cognitive-behavioral therapies,
group support, autogenic training and spirituality.* The field views illness as
an opportunity for personal growth and transformation, and health care providers
as catalysts and guides in this process.
* Certain mind-body intervention strategies listed here, such as group
support for cancer survivors, are well integrated into conventional care and,
while still considered mind-body interventions, are not considered to be
complementary and alternative medicine.
Mind-body interventions constitute a major portion of the overall use of
complementary and alternative medicine by the public. In 2002, five relaxation
techniques and imagery, biofeedback and hypnosis, taken together, were used by
more than 30 percent of the adult U.S. population. Prayer was used by more than
50 percent of the population.1
Background
The concept that the mind is important in the treatment of illness is
integral to the healing approaches of traditional Chinese and Ayurvedic
medicine, dating back more than 2,000 years. It also was noted by Hippocrates,
who recognized the moral and spiritual aspects of healing, and believed that
treatment could occur only with consideration of attitude, environmental
influences, and natural remedies (ca. 400 B.C.). While this integrated approach
was maintained in traditional healing systems in the East, developments in the
Western world by the 16th and 17th centuries led to a separation of human
spiritual or emotional dimensions from the physical body. This separation began
with the redirection of science, during the Renaissance and Enlightenment eras,
to the purpose of enhancing humankind's control over nature. Technological
advances (e.g., microscopy, the stethoscope, the blood pressure cuff and refined
surgical techniques) demonstrated a cellular world that seemed far apart from
the world of belief and emotion. The discovery of bacteria and, later,
antibiotics further dispelled the notion of belief influencing health. Fixing or
curing an illness became a matter of science (i.e., technology) and took
precedence over, not a place beside, healing of the soul. As medicine separated
the mind and the body, scientists of the mind (neurologists) formulated
concepts, such as the unconscious, emotional impulses and cognitive delusions,
that solidified the perception that diseases of the mind were not "real," that
is, not based in physiology and biochemistry.
In the 1920s, Walter Cannon's work revealed the direct relationship between
stress and neuroendocrine responses in animals.2 Coining the phrase "fight or
flight," Cannon described the primitive reflexes of sympathetic and adrenal
activation in response to perceived danger and other environmental pressures
(e.g., cold, heat). Hans Selye further defined the deleterious effects of stress
and distress on health.3 At the same time, technological advances in medicine
that could identify specific pathological changes, and new discoveries in
pharmaceuticals, were occurring at a very rapid pace. The disease-based model,
the search for a specific pathology, and the identification of external cures
were paramount, even in psychiatry.
During World War II, the importance of belief reentered the web of health
care. On the beaches of Anzio, morphine for the wounded soldiers was in short
supply, and Henry Beecher, M.D., discovered that much of the pain could be
controlled by saline injections. He coined the term "placebo effect," and his
subsequent research showed that up to 35 percent of a therapeutic response to
any medical treatment could be the result of belief.4 Investigation into the
placebo effect and debate about it are ongoing.
Since the 1960s, mind-body interactions have become an extensively researched
field. The evidence for benefits for certain indications from biofeedback,
cognitive-behavioral interventions, and hypnosis is quite good, while there is
emerging evidence regarding their physiological effects. Less research supports
the use of CAM approaches like meditation and yoga. The following is a summary
of relevant studies.
Mind-Body Interventions and Disease Outcomes
Over the past 20 years, mind-body medicine has provided considerable evidence
that psychological factors can play a substantive role in the development and
progression of coronary artery disease. There is evidence that mind-body
interventions can be effective in the treatment of coronary artery disease,
enhancing the effect of standard cardiac rehabilitation in reducing all-cause
mortality and cardiac event recurrences for up to two years.5
Mind-body interventions also have been applied to various types of pain.
Clinical trials indicate that these interventions may be a particularly
effective adjunct in the management of arthritis, with reductions in pain
maintained for up to four years and reductions in the number of physician
visits.6 When applied to more general acute and chronic pain management,
headache and low-back pain, mind-body interventions show some evidence of
effects, although results vary based on the patient population and type of
intervention studied.7
Evidence from multiple studies with various types of cancer patients suggests
that mind-body interventions can improve mood, quality of life and coping, as
well as ameliorate disease- and treatment-related symptoms, such as
chemotherapy-induced nausea, vomiting and pain.8 Some studies have suggested
that mind-body interventions can alter various immune parameters, but it is
unclear whether these alterations are of sufficient magnitude to have an impact
on disease progression or prognosis.9,10
Mind-Body Influences on Immunity
There is considerable evidence that emotional traits, both negative and
positive, influence people's susceptibility to infection. Following systematic
exposure to a respiratory virus in the laboratory, individuals who report higher
levels of stress or negative moods have been shown to develop more severe
illness than those who report less stress or more positive moods.11 Recent
studies suggest that the tendency to report positive, as opposed to negative,
emotions may be associated with greater resistance to objectively verified
colds. These laboratory studies are supported by longitudinal studies pointing
to associations between psychological or emotional traits and the incidence of
respiratory infections.12
Meditation and Imaging
Meditation, one of the most common mind-body interventions, is a conscious
mental process that induces a set of integrated physiological changes termed the
relaxation response. Functional magnetic resonance imaging (fMRI) has been used
to identify and characterize the brain regions that are active during
meditation. This research suggests that various parts of the brain known to be
involved in attention and in the control of the autonomic nervous system are
activated, providing a neurochemical and anatomical basis for the effects of
meditation on various physiological activities.13 Recent studies involving
imaging are advancing the understanding of mind-body mechanisms. For example,
meditation has been shown in one study to produce significant increases in
left-sided anterior brain activity, which is associated with positive emotional
states. Moreover, in this same study, meditation was associated with increases
in antibody titers to influenza vaccine, suggesting potential linkages among
meditation, positive emotional states, localized brain responses and improved
immune function.14
Physiology of Expectancy (Placebo Response)
Placebo effects are believed to be mediated by both cognitive and
conditioning mechanisms. Until recently, little was known about the role of
these mechanisms in different circumstances. Now, research has shown that
placebo responses are mediated by conditioning when unconscious physiological
functions such as hormonal secretion are involved, whereas they are mediated by
expectation when conscious physiological processes such as pain and motor
performance come into play, even though a conditioning procedure is carried out.
Positron emission tomography (PET) scanning of the brain is providing
evidence of the release of the endogenous neurotransmitter dopamine in the brain
of Parkinson's disease patients in response to placebo.15 Evidence indicates
that the placebo effect in these patients is powerful and is mediated through
activation of the nigrostriatal dopamine system, the system that is damaged in
Parkinson's disease. This result suggests that the placebo response involves the
secretion of dopamine, which is known to be important in a number of other
reinforcing and rewarding conditions, and that there may be mind-body strategies
that could be used in patients with Parkinson's disease in lieu of or in
addition to treatment with dopamine-releasing drugs.
Stress and Wound Healing
Individual differences in wound healing have long been recognized. Clinical
observation has suggested that negative mood or stress is associated with slow
wound healing. Basic mind-body research is now confirming this observation.
Matrix metalloproteinases (MMPs) and the tissue inhibitors of metalloproteinases
(TIMPs), whose expression can be controlled by cytokines, play a role in wound
healing.16 Using a blister chamber wound model on human forearm skin exposed to
ultraviolet light, researchers have demonstrated that stress or a change in mood
is sufficient to modulate MMP and TIMP expression and, presumably, wound
healing.17 Activation of the hypothalamic-pituitary-adrenal (HPA) and
sympathetic-adrenal medullary (SAM) systems can modulate levels of MMPs,
providing a physiological link among mood, stress, hormones and wound healing.
This line of basic research suggests that activation of the HPA and SAM axes,
even in individuals within the normal range of depressive symptoms, could alter
MMP levels and change the course of wound healing in blister wounds.
Surgical Preparation
Mind-body interventions are being tested to determine whether they can help
prepare patients for the stress associated with surgery. Initial randomized
controlled trials — in which some patients received audiotapes with mind-body
techniques (guided imagery, music and instructions for improved outcomes) and
some patients received control tapes — found that subjects receiving the
mind-body intervention recovered more quickly and spent fewer days in the
hospital.18
Behavioral interventions have been shown to be an efficient means of reducing
discomfort and adverse effects during percutaneous vascular and renal
procedures. Pain increased linearly with procedure time in a control group and
in a group practicing structured attention, but remained flat in a group
practicing a self-hypnosis technique. The self-administration of analgesic drugs
was significantly higher in the control group than in the attention and hypnosis
groups. Hypnosis also improved hemodynamic stability.19
Conclusion
Evidence from randomized controlled trials and, in many cases, systematic
reviews of the literature, suggest that:
· Mechanisms may exist by which the brain and central
nervous system influence immune, endocrine and autonomic functioning, which is
known to have an impact on health.
· Multicomponent mind-body interventions that include
some combination of stress management, coping skills training,
cognitive-behavioral interventions and relaxation therapy may be appropriate
adjunctive treatments for coronary artery disease and certain pain-related
disorders, such as arthritis.
· Multimodal mind-body approaches, such as
cognitive-behavioral therapy, particularly when combined with an
educational/informational component, can be effective adjuncts in the management
of a variety of chronic conditions.
· An array of mind-body therapies (e.g., imagery,
hypnosis, relaxation), when employed presurgically, may improve recovery time
and reduce pain following surgical procedures.
· Neurochemical and anatomical bases may exist for some
of the effects of mind-body approaches.
Mind-body approaches have potential benefits and advantages. In particular,
the physical and emotional risks of using these interventions are minimal.
Moreover, once tested and standardized, most mind-body interventions can be
taught easily. Finally, future research focusing on basic mind-body mechanisms
and individual differences in responses is likely to yield new insights that may
enhance the effectiveness and individual tailoring of mind-body interventions.
In the meantime, there is considerable evidence that mind-body interventions,
even as they are being studied today, have positive effects on psychological
functioning and quality of life, and may be particularly helpful for patients
coping with chronic illness and in need of palliative
care.
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