• Skin temperature measured at the finger. This is a function of blood flow, which in turn is partly determined by stress activation.
  
• Electrodermal response. Skin conductance. This has been studied in a number of ways, including skin resistance, skin conductance reaction and baseline.
  
• Muscle tension. This is determined by monitoring the electrical activity at the neuromuscular junction. Increasing levels of electrical activity reflect increasing levels of muscle contraction.
  
• Respiration: Breathing is directly affected by stress as well as emotional holding patterns. There is also a correlation between activation of sympathetic and parasympathetic mechanisms during inhalation and exhalation respectively.
  " Blood volume pulse.
  " Respiratory sinus arrhythmia's.
  " Electroencephalogram.

There is evidence, as well as it making intuitive sense, that people who demonstrate more reactive physiological arousal mechanisms would be more vulnerable to organ breakdown and the disease process (Adler & Matthews, 1994). Gannon, et al found that those individuals with greater physiological arousal to or slower recovery from a laboratory stressor were more vulnerable to environmental stress than those who were less reactive or faster to recover (1989). Patients with psychosomatic disorders respond more intensely when stressed, particularly in the symptomatic system. (Malmo and Shagass, 1949; Sternbach, 1966). Thus, the psychophysiological profile helps identify risk factors as well as pointing to where Biofeedback training will be most useful.

A typical psychophysiological stress profile or protocol would include a number of segments, each separated by a baseline period. Figure 1 presents one such protocol. The profile always begins with a baseline period. Many clinicians have the patient sit for five to ten minutes for this baseline.

Psychophysiological Stress Profile
1 A 2 B 3 C 4 R

1 = Initial baseline period
A = First stressor: Fast breathing
2 = Baseline restoring
B = Second stressor: Math problem (serial sevens)
3 = Baseline restoring
C = Third stressor: Talk about stress in one's life
4 = Baseline restoring
R = Ask client to relax

Baseline is a significant measure, since all future measures are important in their relationship to baseline. Important considerations for taking baseline include: time of day, any medications taken by the client and when the medications were taken, mood, environmental considerations including room temperature and external distractions. The goal would be to control and keep constant any variable that impacts baseline. When measuring electroencephalogram it is more important for the subject to remain still and to take both an eyes open and an eyes closed baseline.

An initial baseline period is followed by various stress inducing procedures that are interspersed by rest periods. A good profile will include a physical stressor, such as fast, deep breaths; a mental stressor such as a series of math problems solved out loud, which also addresses performance anxiety; and finally either a discussion of a real life stressful situation of the subject, or their visualization of this stressor. Rest periods are typically two to five minutes. The rest periods should be long enough to track the patient's ability to return to baseline. The rest periods should be long enough to track the patient's ability to return to baseline. The profile can conclude by examining the patient's initial pretraining ability to relax.

Factors that need to be considered in assessing the profile include:

• baseline levels compared to a normal range.
  
• the intensity of reaction to the various stress presentations.
  
• which of the psychophysiological variables is most reactive.
  
• speed of recovery of baseline.
  
• ability to relax.

The clinician's ability to identify important aspects of a patient's profile come primarily from one's experience over time with their specific instrumentation. Although instrument makers strive for standardization, it is not possible to control for all environmental factors as well as a clinician's style. One can expect greater consistency with the same bioinstrumentation configuration and clinician. Under similar conditions, it is then possible to begin accumulating data and an ongoing comparison from patient to patient.

Even with this process however, it is important to note that there isn't one single pattern of physiological responding. Williams (1986) and others refer to two or more patterns of physiological responding to stress. In particular, Williams describes two different patterns, one referred to as an immobilization response found, for example with mental arithmetic and the other found with reaction time stressors as well as emotional stress. These patterns differed with respect to hormone secretion, with increases in epinephrine and cortisol occurring with mental arithmetic and not with the second pattern.

Lacey (1950) examined stress response patterns in a group of twelve women. He compared an array of measures including systolic and diastolic blood pressure, palmar conductance, heart rate and heart rate variability. He found that there was no consistent response pattern across physiological systems.

The psychophysiological stress profile serves a number of purposes. To begin with, it is an effective way to begin a Biofeedback program with a client. Efficacy of the Biofeedback process is an important consideration in developing motivation and expectation of the program. The profile offers an opportunity first to demonstrate changes in physiology and then to correlate the changes to the client's cognitive or emotional processes. For many clients who are out of touch with their body this is a significant process. For many, this validates the mind-body connection and how their physical symptoms can be caused by mental and emotional variables.

Factors to consider in the profile include physiological reactivity. This is the degree to which a response system changes to any of the presented stressors. Reactivity has been demonstrated to be correlated with symptom development (Blascovich, & Katkin, 1993, Haynes et al., 1991). Reactivity can be the result of genetic factors, or developmental conditioning, including trauma.

Duration of response also referred to as recovery of baseline is another significant variable to note during the assessment process. The speed of recovery of baseline is a good indication of the flexibility of the system being examined. People who take longer to return to baseline demonstrate impaired resilience and are extending the exposure of their body to the wear and tear of stress.

As an initial introduction to Biofeedback either respiration or EMG can be used to do initial relaxation training at the end of an assessment session. These modalities are selected because of their direct voluntary control and the ease with which to demonstrate the feedback learning paradigm.

Normal Pattern

The stress response as it has evolved is designed to be in balance with its complement, the parasympathetic response. This has been referred to as the relaxation response, and the quieting reflex and can also be considered the body's recuperative or restorative mechanism. That is, it is this mechanism that engages the body in restoring resources used up during stress. While the sympathetic response focuses the organism outward, the parasympathetic response is a more inward focus.

When these two mechanisms are in balance, the body is functioning optimally. Functionally it means that the body's mechanisms for mobilization are in balance with the maintenance functions. Under these conditions, an organism is most capable of fending off disease, in maintaining musculoskeletal flexibility and in keeping blood pressure in a normal range.

The Good Side of Stress

People frequently confuse stress as something that is only negative. But it needs to be recognized that it is a basic adaptive as well as protective mechanism of the body. Let's look at the benefits when we are engaging the stress response in an appropriate way. Activation of the stress response makes the resources and energy of the body available to the organism. In moderation, the stress response makes one more alert and helps to focus and concentrate. This helps in problem solving as well as to feel safe.

The relationship between the stress response and performance is typically seen as the classical inverted "U" curve. Performance improves with increases in stress. However, there is an optimal range, where performance peaks. With further increases in stress performance follows a decremental process. This can be the result of less muscle control with increased tension, or it can be from response stereotypy that inhibits a flexible response or a fast response.

One of the typical difficulties in stress management training is that it is difficult for an organism to make the subtle discrimination of level of stress response. Since it is a defensive and mobilization mechanism, there is an unconscious drive to maintain and even increase the stress response for protection. There is consequently a resistance to modulating this response.

Why does there have to be such a thing as stress management?

Normally the body wants to heal, to restore and to be as healthy as possible. It is designed that way. So why is it necessary to figure out ways to manage the stress response? Why doesn't the body simply manage itself?

Ideally there shouldn't be any conflict between the stress response - which is geared to protection in the moment, and the maintenance functions of the body - which constitute more long-term protection and health. However, the long and short-term functions of the body can be in conflict. When this happens, the short-term survival mechanisms usually win out.

In today's world, there are countless stimuli that trigger danger and the need for mobilization. But very few, if any, signals that allow one to breath that sigh of relief. This results in the continual triggering of the stress response. As you will see below, this picture is compounded by early childhood trauma - chronic or acute.

Through the conditioning process we associate many more stimuli with the need to protect and defend, thus turning on the stress response. Biofeedback is a technology for training a person to reduce sympathetic activation, i.e., the stress response, or to activate the parasympathetic branch of the autonomic nervous system. Once again, we can think in terms of the three variables of activation: frequency, intensity and duration. To this we can add the ultimate lowering of baseline physiological measures.

The effectiveness of Biofeedback is modulated however, by the frequency, intensity and duration with which a person turns on the stress response. Furthermore, psychological issues can cause a person to resist the Biofeedback training. Thus, to be most effective, Biofeedback needs to be integrated into a program that examines the other issues of stress management.

The Two Modern Day Mismatches

Another way of looking at today's stress management problem is what I refer to as the "two mismatches". Mismatch number one has to do with the difference between the environment in which our stress response evolved versus the environment in which we find ourselves using the response. Or, between the environment of the former Hunter/Gatherer society and the modern industrial information society.

This first mismatch results in a stress response that doesn't fit. This refers to the topography of the response. We still maintain a stress response that prepares us for "Fight or flight". It is a defensive preparatory response with greater and greater levels of energy being generated. This mobilization triggers the hypothalamic-pituitary-cortical axis with its autonomic and neurohumoral activation. In the former environment in which this response adapted, the energy would then be expended through physical activity, followed by a period of rest.

Today's environment however, presents an entirely different set of demands. Present day stressors require a more anticipatory response; one in which alertness dominates over mobilization. Which usually require thinking and the skilled use of technology which actually does most of the "work". With today's stressors there is a distinction between threat and attack; between mental and physical response. The environmental demands of modern society and culture usually require restraint, finesse, subtlety, and assertiveness without the extreme physical response. In other words, it does not involve tense muscles as much as an alert mind. The old response topography is not an adaptive response any more; in fact it is potentially self-destructive.

The result of this mismatch is that the mechanism that should help your body maintain homeostasis or balance, is overshooting the mark, and it keeps overshooting the mark, in its attempt to defend.

Unfortunately, since the stress response is a survival mechanism it is very difficult to overcome. It is hard, after all, to go against our instincts. For this reason, there is considerable resistance to modulating the stress response. For Biofeedback to be most effective, this conflict needs to be addressed.

This resistance is heightened by the association of Biofeedback and stress management with "slowing down", relaxing and taking it easy. Since the stress response is so important to an organism, there needs to be some way that they can have permission to modulate it with the relaxation response.

The second mismatch that impacts stress management is the difference between the environment in which we learn how to use the stress response and the environment in which we use it: that is, between the environment of our childhood and our adult environment.

We begin life with an instinctual stress response. Then we learn, based on our experience, how and when to utilize this response. In other words, we have a response that automatically gets triggered if there is danger to our survival, but we then must determine when and where we are in danger.

We learn to use the stress response at a time in our development when we are insecure, and dependent. It is a time when we are not able to protect ourselves. We are vulnerable, lack confidence, and feel inferior to adults.

Of course, it is as an infant, and a child, that we first experience fears of survival: "are my needs for nourishment and shelter going to be met?". This gets expanded to "How are my needs going to be met, and then, "it is my parents who satisfy my needs." So, it then becomes of ultimate importance to have parents close and attentive, to have them love you and want to give to you. In other words, in these early years of your life, you are overly dependent on others to meet your needs. This leads to the development of strategies to assuring that one's parents will meet those needs.

Now, any threat to a child's relationship with their parents will be taken as a threat to survival. This gives parents power, while the child feels impotent. Here is where the problems begin.

The Child Learns the Following Information That Does Not Translate Into Adaptive Adult Behavior:

• You don't have power.
  
• You are at the mercy of others - specifically your parents.
  
• You come from a sense of "lack", since others have what you need.
  
• You internalize your parent's view of the world, no matter how incorrect it is.

Your Needs Become Tied to Your Parents'.

This can be likened to Seligman's concept of learned helplessness, where animals who were unable to escape from shock, learned that they did not have control, so later they continued to act as if they did not have control, even when they did. This is very significant since a sense of control can reduce the impact of stress (Kobasa et al 1981).

The result of these childhood issues is a particular "stance" toward the rest of the world: More defensive, more alert, and more vigilant. The outside world is bigger than you, and more powerful - thus there is fear; and this results in the stress response being triggered more readily. It also results in an ongoing psychophysiological bracing as if continually expecting an attack.

Certain childhood environments exaggerate this phenomenon while other environments and cultures tend to buffer the child from these factors. For example uncertainty, lack of security, and abusive treatment and trauma will intensify this effect. Enhancing security, providing love, attention, acceptance and self-efficacy will minimize this effect.

In indigenous societies, there are rituals that adolescents are lead through to help them make the transition into the adult world. The ritual serves to help the person shed many of the attachments of their childhood. It is usually a transformative experience used to help the adolescent feel like they have become an adult, with all the responsibilities and power that the adults carry.

In such societies, the elders help the transfer of power to the new generation, after all it is in the interest of the entire group to have the young adults feel such a sense of power and responsibility. Unfortunately, in more modern cultures this custom or ritual has been neglected.

Personality Factors

One of the ways that we learn to deal with this sense of inadequacy is by developing a persona. This is a healthy aspect of development. We create an image that is presented to the outside world. This image is designed to maximize success in getting one's needs met.

The problem occurs when there is a discrepancy between this image that is projected and what one truly believes about oneself. The greater this discrepancy, the more uncomfortable in the persona, and the greater the tension and fear of being discovered. The greater this discrepancy, the more easily the stress response gets triggered.

Since the stress response occurs when there is an appraisal of danger, the more self-confidance, the fewer the situations that will trigger the stress response. Also, the more one feels positive self-regard, the more likely to perform self-care aspects of stress management, of which Biofeedback is included.

Emotional Factors

Emotions have a psychophysiological component. Emotions that have not been acknowledged or fully addressed contribute to an individual's ongoing physical holding pattern (Reich, 1945; Lowen 1958). Sometimes referred to as bands of tension around the body, these patterns interfere with relaxed breathing, affect blood flow and contribute to chronic muscle tension.

When emotions and their sources are addressed, and the client is able to physically release them, there is a more supple tone to the body. It enhances physical flexibility. This allows for the more effective training of Biofeedback.

Comprehensive Stress Management Approach

The basic focus of any Biofeedback assisted stress management program is on two facts: 1) A person's stress response, or habitual bracing patterns have become more and more conditioned to environmental stimuli, and 2) The body gradually adapts or numbs itself to higher and higher levels of tension or arousal. These more frequent and higher levels are typically only recognized when the person becomes disturbed by the symptoms of stress: headaches, muscular aches and pains, insomnia, fatigue, hypertension and gastrointestinal aches.

One way of looking at this process is that the increased conditioning of the stress response results in the deconditioning of the body's homeostatic mechanisms. For example, some people find it uncomfortable when instructed to deepen their breathing. This is because the intracostal muscles that expand the chest are not used to stretching.

Biofeedback and other relaxation techniques can be the core of a total approach to stress management. Thus Biofeedback training, in some sense, is a reconditioning of the body's relaxation mechanisms in order to restore homeostasis.

Personality and cognitive factors come into play in the stress management process because some people cannot give themselves permission to relax, or feel it isn't safe. This can result in unconscious sabotaging of the process. A person who experienced childhood trauma for example, may unconsciously trigger their arousal mechanism when they are becoming too relaxed, as a protective mechanism. This and the avoidance of feelings are probably the main causes of relaxation induced anxiety.

Arousal Reduction or Autonomic Deactivation

The primary model for Biofeedback assisted stress management as well as most approaches to psychophysiological disorders is one of arousal reduction or reducing tension. This is also the basis for assessment of the psychophysiological stress profile. We expect to observe elevated baselines or specific physiological reactivity to a stressful situation or imagined stressful situation, or a slow return to baseline. Unfortunately the research is not clear-cut.

If we examine the literature on tension headaches, for example, it appears that most studies report differences between pain patients and controls, in either baseline EMG readings or readings during stress, from temporalis, frontalis or trapezius muscles (e.g. Schoenen et al. 1991; Hatch et al. 1992), although some studies do not show such differences (e.g. Flor and Turk, 1989; Marcus 1992). Furthermore, if we look at the correlation between change in EMG and reduced headaches, here again, the results are ambiguous.

There are a couple of reasons for these discrepancies. The first has to do with where and what is being measured and the second has to do with the difficulty recreating real life situations in the office or laboratory. In the psychophysiological profile described above, by using three different stressors and monitoring multiple end-organ response systems, one is more likely to observe relationships between reported symptoms and the psychophysiology.

It is also not uncommon to be able to train response control, such as raising peripheral temperature or lowering skin conductance levels without a shift in baseline. These patients will typically note a reduction in their symptoms. In other words it appears that there is an enhanced resiliency of the system even though resting levels may not change.

Our stress response is only one of two responses programmed into our nervous system, the other is the autonomic parasympathetic response of recuperation. Clients presenting with stress related symptoms, have lost resiliency of their autonomic system. In particular, there is a reduced ability to turn on these parasympathetic mechanisms. Most frequently, this is indicated by difficulty with sleep pattern, various musculoskeletal aches or the dysregulation of other bodily systems.

Autonomic imbalance is the result of activating the stress response too frequently, too intensely and for too long a duration. The management of stress therefore becomes the adjustment of these three variables. Biofeedback and other relaxation training paradigms can be considered the retraining of parasympathetic activation or arousal deactivation. Here we approach the problem at its biological roots, restoring autonomic balance.

Employing multiple response systems in stress management training is like cross training for conditioning. In addition, with multiple systems there is a greater likelihood of achieving initial success and thus positive reinforcement.

The effectiveness of Biofeedback however, lies in embedding it within a more comprehensive stress management approach. For example, Biofeedback can reduce the intensity of one's stress response. If however, at the same time a person's catastrophic expectations result in the frequent triggering of the stress response, the benefits will be negated. Alternately, if a person is hypervigilant due to childhood trauma, they will be more resistant to Biofeedback training, and may unconsciously sabotage the process. In other words, cognitive and personality factors need to be simultaneously addressed.

Choosing Which Modalities to Train

We have many ways of monitoring the physiological changes that represent aspects of the stress response. The first step in determining which modalities to utilize during training comes from the evaluation of the psychophysiological stress profile. One would want to focus on the modality that demonstrates the greatest lability or divergence from an optimal baseline during the profile. It may be that this modality is related to the presenting symptoms. In other words, muscle tension for a headache patient and skin temperature for a person with hypertension.

This can be referred to as symptom specificity as well as individual response specificity, and has been frequently demonstrated. For example, Moos and Engel (1962) demonstrated that arthritic and hypertensive patients had more reactive musculoskeletal and blood pressure responses respectively.

An alternate strategy might be to focus on a modality that is less disturbed. This system may be easier to train, thus giving the client early initial success. This success is very important in creating efficacy for the process and motivation for the client. As mentioned above, it can be useful to train multiple systems for enhanced autonomic conditioning and resilience and to maximize generalization to the real world.

Initial training sessions may also include a demonstration and training of the opposite response. For example, brief hyperventilation will typically cause an alteration in skin conductance. If the client is then given instructions/strategies to relax, it will be easier to observe a reduction in the skin conductance level, from this elevated level. If EMG is being monitored, introduction of the progressive relaxation procedure will accomplish a similar demonstration about muscle tension. This is where the client is asked to tense a particular muscle or group of muscles prior to relaxing them. In general, training of responses in both directions enhances psychophysiological control.

It is reasonable to expect the client initially to be somewhat activated due to the newness of the situation. This is referred to as the orienting response. Thus, an initial increase in indicators of arousal may occur. Clients should be somehow prepared for this experience in order to minimize a negative cognitive-emotional-physiological reaction.

In fact, overall, how a client is oriented to the Biofeedback process is very important. Many people, particularly those with stress related problems, are self-critical and/or have performance anxiety. These clients, particularly those with a Type A character, will approach Biofeedback with the same intensity and pressure that they place on all their other activities. In other words, simply engaging in the process and observing their physiological responses will trigger tension. The client "tries" to succeed in the same manner that they expend effort in other tasks. When they are not completely successful their self-criticism adds to this process. These factors can place an overwhelming burden on the Biofeedback training.

It is for these reasons that the client needs to be appropriately prepared and oriented to the training. The following factors need to be emphasized:

1. This is a training process not a test.
   
2. Training occurs no matter which direction the signal goes.
   
3. Initially there isn't an absolute goal only a desired direction for the signal.
   
4. Avoid responding to questions regarding what a "normal" response should look like.
   
5. This process, to be successful, needs to be approached differently then all client's other activities, that is: it is a process of letting go. It does not benefit the client to "Try hard", since this itself creates tension.
   
6. The process is working even when client does not see the results.
   
7. Much of the learning is unconscious, outside of clients awareness.
   
8. Length of training varies from person to person.
   
9. Initially the experience may feel uncomfortable or disorienting and that this is normal.
   
10. If the client shows up and does the prescribed home practice, they will be successful.

Generalization of Training

Using Biofeedback to manage stress requires transferring the training from the relatively safe office environment to the outside world. This involves four steps:

1. Regular practice of a relaxation response.
   
2. Greater and ongoing awareness/monitoring of tension.
   
3. Incorporation of learned skills.
   
4. Generalization procedures to better associate the trained calmness to stressful life situations.

1. Regular practice of a relaxation response.
   
   
2. People experiencing stress related problems have impaired ability to turn off sympathetic mechanisms. As noted previously, the client can be considered to be out of condition with respect to their autonomic nervous system and related physiology. Practice is required to recondition these mechanisms. For example, initially when doing peripheral skin temperature Biofeedback it is not uncommon to achieve an initial increase in temperature. This increase however may not be maintained since the small muscles surrounding the blood vessels are unable to maintain the change.
   
   
3. Greater and ongoing awareness of tension.
   Since there is an habituation to musculoskeletal tension, it is important to set up some type of stimulus, or reminder system throughout the day to check in with one's body to notice any bracing or holding, or inappropriate breathing pattern.
   
   First, one should expect a person to revert to existing body tension patterns, even seconds after a relaxation exercise. A very useful technique during Biofeedback is to focus on tension in the shoulders, aided by EMG monitoring. After a period of Biofeedback in which the EMG levels decrease, shift the focus to other modalities and other parts of the body. When you return to the shoulders and EMG a few minutes later, invariably the tension level will have gone back up.
   
   This demonstrates both tension patterns as well as muscle memory of tension levels. The body wants to return to its most familiar orientation, even if this is one of tension. It is easy to help the client realize that if this takes place in the office, it is certainly occurring out in the world, particularly the work environment. Periodic reminders are therefore needed to help the client notice this increase in tension. A simple "Body-scanning" technique involves having the client bring their awareness through their body, stopping at the various muscle groups, and noting any holding, tension or other form of bracing.
   
   This is part of an awareness training process. Stress management first involves noticing an imbalance in order to make the physiological adjustment. By setting up these reminders, it is possible to begin shifting the long-term pattern.
   
   
4. Incorporation of learned skills into one's daily routine:
   Following the body-scanning, a very simple process of a series of relaxation breaths (diaphragmatic breathing) and releasing muscle tension as learned in the Biofeedback will be effective in resetting tension levels.

Generalization Procedures to Better Associate the Trained Calmness to Stressful Life Situations:

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