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SCIENCE, PRACTICE AND PHILOSOPHY
by Dr Craig Hassed
Senior lecturer, Monash University Department of General Practice
867 Centre Rd, East Bentleigh, Victoria 3165, Australia
Ph: 61 3 85752205 Fax: 61 3 85752233
The cause and effects of stress 3
The science 5
Mapping mind and brain 5
The placebo response 7
The experience of pain 8
The effects of stress reduction 8
Autoimmune diseases 14 Allergies 15
The mind and genetics 16
Personality and illness 16
Heart disease 19
Social factors and health 30
Humour and health 33
Music and health 34
Food for the mind 35
Cognitive decline 37
Spirituality and health 38
The practice 43
Mindfulness meditation 45
The philosophy 46
Since earliest times ancient approaches to health have been, in essence, holistic. Well-being, illness and healing were strongly connected to the mind, society, morality and spirituality. In the 19th and 20th centuries, however, with the rise of a more materialistic approach to science generally, this holistic view has been replaced by a more mechanistic and reductionist one. Most recently, with the rise of collaborative research and new fields of science such as mind-body medicine (MBM), there is gathering evidence that there was a practical wisdom in these ancient approaches. Although the mechanisms which science attempts to elucidate are infinitely complex the principles are extremely simple and, as such, they have enormous potential for successful integration into clinical practice. This uptake, wherever possible, needs to be governed by sound clinical practice and best available evidence.
MBM simply reminds us that psychological states like chronic stress, depression, anxiety and fear and our social context produce profound effects upon the body. These effects express themselves all the way from the obvious muscle tension down to the way our genes express themselves. Over time negative mental and emotional states take a heavy toll on the body and are a significant risk factor for illness. Research suggests that many, but not all, psychosocial interventions can play an important part in ameliorating this effect. MBM has enormous scope and clinical potential but has been relatively slow to make its way into mainstream medical education and practice. This lack of general awareness may be the product of many things including a lack of access to information, bias against what does not fit current scientific paradigms and lack of funding for things which are of lesser commercial potential. Ease of access to skills and information through medical literature and education will be important means for redressing some of this imbalance. Growing community interest and a need to foster approaches which provide superior cost-benefits are also likely to increase the uptake of MBM approaches.
This article will give a broad overview of the medical literature in the field of MBM, discuss some of the practical aspects of using a mindfulness meditation approach to stress management and raise some of the interesting associated philosophical and practical questions.
The father of Western medicine, Hippocrates, said that the “human being can only be understood as a whole” but what is the whole person? To the ancient Greeks, as with other ancient healing systems, the whole person includes the physical body, mind, emotions and spirit or consciousness. As this individual was made of the same elements as the society and environment so there was an implied continuity or inter-dependence between every level of the individual and the individual and the world. The physical body was viewed as the most superficial aspect of a person and was seen to be ‘moved’ or enlivened by the deeper layers of the self with consciousness being the primary substance of our being. What effects one part will impact on all the others. This inter-relationship as defined by ancient healing systems is not dissimilar to the WHO definition of health.
“A state of dynamic harmony between the body, mind and spirit of a person and the social and cultural influences which make up his or her environment.”
Holism is an age-old concept but much of what has dominated modern science and medical research has reflected an attitude of ‘reductionism’ and ‘materialism.’ As a reaction many people are once again turning towards more traditional and/or alternative approaches to their health care. The oft-cited reason is the search for a ‘holistic philosophy’ as to why people look for alternatives to orthodox medical care.1 Among ailments anxiety and chronic pain are the most likely to predict a search for non-orthodox medicine.
With advances in medical research which attempt to ‘reconstruct’ the human being we are starting to appreciate just how profound the mind and consciousness are in determining health and ill-health. These effects take place through both physiology and behaviour. Acknowledging the role of the mind does not deny the important role of physical risk factors and treatments. Indeed, generally the best approach will be to use the best that physical medicine has to offer but to use it in a holistic context. Recognising, for example, that stress and emotion play a role in asthma does not preclude or ignore the importance of pharmacological treatment nor the need for careful monitoring.
In discussion about MBM much debate arises about the distinction, if any, between mind and brain. In one view the mind is non-physical and constituted by thought and emotion. The brain is the organ which translates thought and emotion into biological or chemical activity which subsequently regulates the functions throughout the body. If someone says that an illness, pain, or stress is ‘in the mind’ they are correct, but it also expresses itself in the brain and thence the rest of the body. There are undoubted physical sequelae of depression, stress and other psychological and emotional states.
The interest in MBM has spawned a number of new fields of scientific endeavour such as psychoneuroimmunology (PNI) and psycho-oncology and has renewed interest in the interface of medical science with metaphysics and philosophy. This shift in perspective, while offering great potential for effective and good quality health care, also challenges commonly held paradigms and rigid ways of thinking but an openness of mind must be balanced with sound research and clinical experience. Anyone who wishes to form an informed and considered point of view in the field of mind-body medicine should not be too ready to accept any claims about the role of psychological factors on health unquestioningly. Nor should they be rejected without question.
“You need to keep an open mind, but not so open that your brain falls out.” Prof. A. MacLennan
Any one piece of research data is only one piece of an enormous jigsaw puzzle and does not make a whole picture. It must be taken in context with other research and where discrepancies are found then attempts must be made to explain these. This paper will attempt to help bridge some apparent gaps and inconsistencies between different systems of thought and language. This paper cannot pretend to be definitive or exhaustive in its examination of MBM. The area is too vast to be covered in any one text. It will, however, give an overview of the main principles and highlight significant points with key papers.
The cause and effects of stress
Stress is a commonly used term which covers a wide range of human experiences. Some describe it as a “perceived inability to cope”, others as when “demands exceed means.” We often use it to describe the physical effects of sympathetic nervous system (SNS) activity associated with anxiety or fear such as muscle tension, tremulousness, clamminess, rapid heart beat. These manifestations of the ‘fight or flight response’ can lead on to tiredness and many other stress-related symptoms associated with chronic stress. For some stress is a word also used to describe psychological, emotional and existential states like confusion, distractibility, forgetfulness, worry, fear, anger, frustration, aimlessness, despondency and depression. We often cycle through a variety of these states. Stress and depression are well known to be connected and western societies are observing similar increases in rates of depression and suicide. Accumulating evidence suggests that stress hormones may play a role in the development of psychiatric disorders2 as well as the direct effects of stress on serotonergic pathways3.
Some predictions estimate that depression may be the major cause of morbidity within a few decades.4 It certainly seems that we are seeing higher rates of depression occurring at younger ages. Suicidal ideation is alarmingly common in adolescents with some reports suggesting that 1 in 2 young people experiencing high levels of psychological stress and as many as 1 in 4 15-24 year-olds presenting to GP’s for any reason experiencing recent suicidal thoughts.5 Most of the adolescents did not present for psychological reasons. Therefore, one cannot take stress lightly nor the label ‘stress’ at face value without exploring fully what a person means by it.
Depression is being diagnosed, and pharmacologically treated, in younger age groups but serious concerns about this approach have been raised in recent major reviews.6 7 Part of the overuse may be market-driven. The efficacy of many antidepressants in childhood depression may have been exaggerated and the benefit from drugs is of doubtful clinical significance. Furthermore, adverse effects have been downplayed. Significant question about the use and research-base of these drugs have been raised.
Much research has gone into researching the effects of stress in recent years.8 9 10 Whether real or perceived, evidence suggests that the stress of modern life is increasing at an alarming rate; 45% over the last 30 years in some surveys.11 This could be explained by both increased awareness of stress and also more stressful and busy lives. The rapid increase in the amount of change socially as well as job insecurity, the speed of life, competitiveness and many other factors probably all contribute.
Chronic stress or the accumulation of a number of minor stresses is a contributor to, or direct cause of, many illnesses. On one level the fight or flight response is a natural, necessary and appropriate physiological response to an exceptional situation. For example, if one is about to be bitten by a snake or be run over by a truck then one may need to respond quickly to get out of the way. This response, based on a clearly perceived threat, is encoded into our physiology to preserve life by allowing the body to respond to dangerous situations. Such changes include elevation of blood-pressure and heart rate, diversion of blood-flow to muscles and away from the gut, platelets becoming ‘stickier’, short-term mobilisation of white-blood cells and many other events. These are to help the body cope with demands and potential injury. (Strangely, seeing your GP coming at you is enough to put your blood pressure up enough in fact to cause up to one quarter of patients being diagnosed inappropriately with hypertension.12 This is called ‘white-coat hypertension’.) When the situation is over the physiology would return to rest if the mind left the event in the past and moved on. The replaying of the event in the mind, however, can reproduce the stress response even though the event is over. In the most extreme cases this replaying can lead to what is called ‘post-traumatic stress disorder.’
A very interesting review article seemed to provide a new perspective13 on the stress response not often acknowledged. This review article pointed out that much of our research on the stress response over the years has focused on men hence the fight-or-flight response, which is largely a male response, has become the predominant paradigm. But there is good evidence to suggest that women do not respond to stressful situations in entirely the same way. The article said, “We suggest that the female stress response of tending to offspring and affiliating with a social group is facilitated by the process of ‘befriending’, which is the creation of networks of associations that provide resources and protection for the female and her offspring under conditions of stress.”
Both males and females have the necessary mechanisms for activation of the fight-or-flight response if required, but it seems that men are especially built for this response especially because of the presence of testosterone.14 Testosterone also seems to have a role in the development of ‘rough and tumble play’ and sport for boys which is a part of normal development but excessive testosterone levels are implicated in excessive physical aggression and crime. Female aggression, on the other hand, is more ‘cerebral’, i.e. it seems more likely to express itself “in the form of gossip, rumour spreading and enlisting the cooperation of a third party in undermining an acquaintance.”15 In terms of the more general response to stress, however, Taylor et al suggested that as the female of most species is involved in tending the young that they have the biological or behavioural disposition to tend-and-befriend. These effects are largely mediated through female hormones like oxytocin and oestrogen16 which are particularly active in periods like breast-feeding as well as in social interaction and caring physical contact. They seem to have a calming effect as well as being an ‘antidote’ for the fight-or-flight response.17 Oxytocin levels can be influence by many things as one would expect, for example, they can be increased by a relaxation massage or close relationships and reduced by sad emotions or social isolation. This might be part of the explanation behind interesting clinical studies demonstrating things like massage and maternal handling improving the survival of pre-term infants.18 Of course none of this suggests that men can’t tend and befriend nor that women can’t elicit the fight or flight when required but it does suggest that each gender is more or less adapted for one or other response which, taken together, is an example of the complementarity of nature.
So although a level of stress can be associated with motivation, and although the ‘fight or flight’ response can be entirely necessary in extreme situations, the vast majority of stress experienced in daily life is not appropriate or helpful. The unnecessary and excessive switching on of the stress-response, which we might call inappropriate stress, though common, is not healthy nor does it help us to cope with demands. In fact it does quite the opposite. Here the mind is agitated and unfocussed. One can, and usually does, become overwhelmed with imaginings, projections and anticipation which are given a reality they do not deserve. Rather than a highly conscious and aware state this is the opposite. Examples might include projecting fears into the future about exams or interviews, catastrophising about upcoming events and habitually recreating past anxieties and conflicts. Here the stressors are in the mind, not in reality. The body, however, will faithfully reproduce the stress response until it is told to stop regardless of whether the stressor is real or imagined. If one imagines a rope to be a snake the body will react to the perception, not the reality. Even events which are actually happening may or may not cause stress depending on what the mind thinks about them. Events are just events unless our thinking interprets them as stressful and threatening.
Restful alertness, calm and focused - peak performance
Poor performance / burnout
Fig. 1: Stress-performance curve
“There is nothing either good or bad but thinking makes it so.” William Shakespeare
“The optimist proclaims that we live in the best of all possible worlds; and the pessimist fears this is true.” James Cabell
Thus the mind has the key role in eliciting the stress response through its functions of perception, cognition, interpretation, and conditioning. Learned patterns of coping and personality styles are possibly more important than a situation itself and so one can readily see how important techniques such as meditation, relaxation, cognitive-behaviour therapy (CBT), rational-emotive therapy (RET) etc. are in helping to reverse the effects of this inappropriate stress by attacking it at its cause; thought. Reviews of the literature suggest that cognitive and relaxation based forms of stress management in general practice seem to be most effective and that working in groups seems to potentiate therapy.19
If the stress-response is severe or prolonged enough it negatively effects health, lifestyle, relationships and behaviour as we shall later see. As such it places responsibility on the individual for their own health by empowering them to understand themselves better and take charge of these responses. Any response to stress which merely apportions blame to environment will be of very limited success as it ignores the most important element in the process, the person responding to the environment. This, of course, does not preclude the fact that a more conscious and focused response to an event may be exactly what is required. If there really is a snake in the vicinity then it may need evasive action. Furthermore, one must be careful that in the acknowledgement of the role of the individual in generating their own stress and illness as a result it is important to not encourage a process of self-blame. Responsibility is much more about fostering a healthy ‘ability to respond’ than it is about blame or recrimination.
Mapping mind and brain
It is beyond the scope of this article to review the vast field of neurosciences which seem to be giving us plausible ways of understanding mind-body communication in biological terms but some general comments might be useful at the outset. This topic will be dealt with in far greater detail in the later section on the philosophical issues.
The materialistic view of the mind and soul has a long history. Attempts to find the seat of the soul in the brain date back to ancient Egypt and can be traced through ancient Greece right up to the modern day. Today, with the rise of the neurosciences, brain scanning techniques and genetics, we are discovering biological correlates for all psychological phenomena. Even spiritual experiences are being examined, described and demystified. For some this is seen as a direct challenge to metaphysical explanations of the human condition and for others it is a fascinating elucidation of the details underpinning the metaphysical view.
“Cartesian dualism was dominant for centuries and still infiltrates our thinking today. But there were always scientists who held that mind and brain function were one and the same, and during the nineteenth and early twentieth centuries many of them worked feverishly hard to produce coherent brain maps.” 20
On this view, awareness can be traced to activity in the brain’s reticular formation, emotions to the limbic system, stress to the Hypothalamic Pituitary Adrenal (HPA) axis and mysticism to the temporal lobe etc. A material view of existence might conclude that the cause of psychological phenomena is chemical and the effect of these chemical reactions is thought, emotion and even consciousness. Thus the cause of depression or anxiety is often described to patients as a chemical imbalance in the brain which therefore largely needs a chemical solution, principally antidepressants and sedatives.
From the early twentieth century the brain began to be mapped to specific functions and this early work led to some naïve and simplistic approaches to treating mental illness and behavioural problems. It was by the 1940s when this information began to be used in ‘therapeutic’ settings with the rise of frontal lobotomy.21 Psychosurgical techniques have understandably been relegated to history although other physical techniques like Electro-Convulsive Therapy remain in use and newer techniques like Transcranial Magnetic Stimulation (TMS) are being developed. The mainstay of the modern approach to mental illness since the 1960’s are pharmaceutical therapies.
With the rise of the neurosciences, many long-held myths about the brain and Central Nervous System (CNS) are being challenged. It has long been held that after initial development the CNS changes very little for the rest of the life, but it seems that it is subject to major modification in response to experience, memory, attention and emotion. The adaptability of the CNS is exemplified by recent experiments examining the effects of stress on the animal brain.22 It has been found that by stressing an animal, chemicals such as tissue-plasminogen activator (tPA) were crucial in the remodeling the brain’s anatomy, particularly the part of the brain called the amygdala which is associated with emotions and anxiety states. This ‘rewiring’ was reversed if the animal was allowed to return to a stress-free environment again. Such modeling and remodeling are likely to be more responsive in younger than older animals and has significant implications for the long-term development of anxiety and depression. Memory of emotionally traumatic events with a high level of reactivity seems to reinforce this wiring and may play a significant part in post-traumatic-stress-disorder.
Brain scans show that anticipation as well as physical events have significant effects. Thoughts of eating of chocolate, for example, will most definitely ‘light up’ parts of the brain associated with rewards and pleasure.23 Some parts of the brain light up with rewards, others with addictions and others with punishment. Because of these correlates there are likely to be potential forms of therapy for treating things such as gambling addiction by targeting these biochemical reactions.24 How one can change the biological correlates of these conditioned behaviours and addictions with behavioural therapies is not yet fully known.
More peaceful states of mind, such as those induced by meditation, are associated with increased levels of activity in the brain, specifically the left frontal lobe, associated with better mood and also improved immunity.25
The CNS has many mechanisms to allow it to adapt to the environment, repair damage, and slow the aging process.26 These mechanisms include “neurotrophic factors and cytokines, expression of various cell survival-promoting proteins, … protection of the genome by telomerase and DNA repair proteins, and mobilization of neural stem-cells to replace damaged neurons and glia.” Such mechanisms can be impaired by various forms of toxic and oxidative stress and also have significant implication for the development of neurodegenerative disorders like Alzheimers Disease (AD) and Parkinson’s disease. Neuroprotective mechanisms can be enhanced by dietary factors (caloric restriction, folate and anti-oxidant supplements) and behavioural factors (intellectual and physical activities).27 This is being confirmed now in prospective studies, for example, during 4.9 years of follow-up of a middle-aged to elderly population those high in distress proneness (90th percentile) had twice the risk of developing AD than those low in distress proneness (10th percentile). The conclusion of the study was that “proneness to experience psychological distress is a risk factor for AD, an effect independent of AD pathologic markers such as cortical plaques and tangles.”28
A purely physical scientist will tend to stop with the physical. ‘The causes are physical and therefore the remedies will be also.’ Pharmacological treatments are therefore directed at reversing these effects and indeed, they can provide some useful symptomatic relief but there is considerable contention about whether these medications can get to the cause rather than just treating the effect. Can thought, emotion, motivation and even the search for meaning really be reduced to biochemistry and genetics?
“We will not understand important things like “love” by knowing the DNA sequence of homo sapiens.… If humanity begins to view itself as a machine, programmed by this DNA sequence, we’ve lost something really important.” Francis Collins, Head of the Human Genome Project29
Religious experience is among the hardest fields of psychology and sociology to study because it is so hard to define, isolate and measure. Can it simply be reduced to chemical and electrical changes in the brain? There has been the identification of biological and neural correlates of spiritual experiences and to an extent they have been artificially induced through drugs or electrical stimulation. “During religious recitation, self-identified religious subjects activated a frontal-parietal circuit, composed of the dorsolateral prefrontal, dorsomedial frontal and medial parietal cortex.”30 Activity in temporal lobes of the brain is also associated with a number of religious and psychological phenomena including blurring of interpersonal boundaries.31 Whether the biological changes are caused by psychological or spiritual phenomena or the effect of them is a source of ongoing debate.
Recent studies are linking the practice of meditation to specific changes in brain activity. fMRI identified significant signal increases were observed “in the dorsolateral prefrontal and parietal cortices, hippocampus/parahippocampus, temporal lobe, pregenual anterior cingulate cortex, striatum, and pre- and post-central gyri during meditation,” indicating that meditation activates neural structures involved in attention and control of the autonomic nervous system.32 Such changes also correlated to improvements in mood. So is intention and attention merely a chemical state or is the chemical state being driven by intention and attention.
The other way of viewing things is to see that the physical events are not the cause but rather the effect of what goes on in the mind. The causes being in the mind does not preclude the effects being biochemical but it does mean that the remedies are in the mind. But even if the causes are mental that does not necessarily mean that one can readily change physical conditions, at least in the short term, purely by thought. Our mental state may influence the speed of wound healing but we cannot necessarily wish the wound away. We may have considerable influence on our neurochemistry but that does not mean that medications may not be indicated and necessary for a significant mental illness. That having been said, we do not yet fully know the potential for the body’s ability to heal itself with the mind.
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