To help organize this status report on Perceptual Control Theory Psychotherapy (PCTP), I will use a scheme proposed by Maher (1989). He has listed seven components which any complete theory of psychotherapy should address. Any theory of psychotherapy must contain statements which refer to: (a) the useful material to be elicited, (b) listening/observing: how to and what for, (c) higher-order description of patient and target of change, (d) therapeutic goals and directions of change, (e) principles of therapeutic change, (f) general therapeutic stratagems, (g) conditions-operations-consequences. First the basic ideas of PCT will be described. Then a description of PCTP in terms of Maher's seven components will be given. Readers familiar with PCT can go directly to the second half of the paper on Psychotherapy.
Newcomers to PCT usually misunderstand and negatively react to the concept of control based on preconceptions about what it means. I will begin by defining and explaining the PCT idea of control. A person controls some aspect of the environment when the person is able to produce a consistent result in the environment even though the environment is changing in ways which should alter the result. In order to produce a consistent, desired result, the person must be inconsistent in actions to compensate for the changing environment. In PCT, actions are expected to vary in order to achieve some consistency in perceptions.
Common examples of "control" in mechanical systems are the temperature control systems in buildings and speed control systems in cars. The consistent result in the former example is a temperature reading which is fairly constant despite changes in outside weather. The consistent result in the latter example is a car speed which is fairly constant despite variations in terrain and other factors.
It is more difficult to say that another person is controlling a perception than to make this judgment for oneself. One must know what happened and what the person intended to happen in order to say whether a perception is controlled. If what happened is what a person intended to happen, then the person is controlling a perception. Observing the actions of another person is not usually sufficient information to make his judgment without some uncertainty.
One cannot always know what a person is "doing" by watching what they are doing. Imagine that we are driving a car and are observing other cars. Let us consider car A. We note that car A is going about 70 miles an hour. Is the speed of car A a controlled perception of the driver of car A? The answer depends on whether the driver wants to be going at this speed. How can we know? We can pull in front of car A and gradually slow down. If car A moves into the left lane and resumes going 70 miles an hour, then we have some evidence that the speed of the car is a controlled perception. The driver of car A might convince us of this conclusion as he passes our car when we note his angry look, gestures, and unhearable verbalizations. If, on the other hand, the driver continues to stay behind us as our car goes 55 miles and hour, the evidence suggests that the driver is not wanting to be going at 70 miles an hour. Simply observing the speed of car A is not enough information to know whether it is a controlled perception of the driver. The above example uses a method called the Test for the Controlled Variable. This will be discussed later in the paper when used in the context of therapy.
Some further everyday examples of the PCT idea of control follow. The pitcher had good control today." This means that he could throw the ball where he wanted within the strike zone. "The fire was under control." This means that the firepersons could stop it from spreading and were in the process of extinguishing it. "The AIDS epidemic is not under control." This means that we cannot stop people from getting AIDS and that we cannot stop people from dying who contract AIDS. " A person's eating is out of control." The person is eating more than s/he should and is gaining weight. "A person's spending is under control." The person is not spending more money than is allowed by his/her budget and is not going into debt.
In each of these everyday examples, the actual result is compared to the desired result. An identical match defines perfect control. The smaller the difference, the better the control. The actual result can vary. Two classes of factors which determine the value of the actual result are (a) the actions of the person on the environment (feedback), (b) the influence of all other factors on the environment (disturbances). The person is the one who chooses what the desired result should be and so, this is one independent variable. If the person took no actions, the actual result will be determined by the disturbance factors and this is the other independent variable.
In PCT, the primary interest is not in actions. Actions will change in any way they have to in order to obtain the desired result. The primary concern is with perceptions (experiences) and the control of experiences.
PCT Perception Ideas: The meaning of the word perception in PCT is much broader than in ordinary use. The PCT idea of perception includes the more traditional ideas of sensation, perception, and cognition and metacognition. Any experience which starts from sensory stimulation and results in nervous system activity in sensory pathways is a perception. Any memory of such an experience is also a perception.
Awareness and perception are separate concepts in PCT; a person can perceive with or without awareness and a person can have awareness with or without perception. Awareness is part of the Reorganization system which produces learning and development; the Reorganization system will be discussed in the next major section of the paper. PCT has a well worked out description of the different levels of perception and the relationship between any two levels of perception to which I now turn.
The Perceptual Control Theory view is that any particular perception, let us call it Perception A, is a part of a hierarchy of perceptions. Perception A is derived from a combination of several lower level perceptions and is qualitatively different in kind from the lower level perceptions. Perception A, in turn, could be a building block for a higher level perception; it is a means by which a higher level perception forms. Asking the question of how one achieves Perception A requires reference to lower level perceptions. Asking the question of why one wants to achieve a Perception A demands reference to higher level perceptions.
While Perception A is subjectively, qualitatively different from other perceptions, it is an unusual feature of PCT that all perceptions are represented by a unidimensional, continuous neural variable such as impulses per second. At a biological level, all perceptual variables look the same no matter what level of perception. This feature allows error signals at one level to result in reference signals at the next lower level.
The current version of Perceptual Control Theory includes eleven levels of perception in the hierarchy which I will now describe by means of an example. Imagine that you are taking a walk in your neighborhood. If you chose to become aware at the configuration level of perception (3rd level), then you would see objects of different kinds as you walked. If you paid attention to the sensation level (2nd level), then you would notice the properties which make up the objects such as color, shape, size, texture. If you paid attention at the intensity level (1st level), you would note that some stimuli seemed stronger than others.
Tuning into the transition level (4th level), you become aware of small changes over time. For example, you may note that the light illumination changes, the leaves move, etc.. At the event level (5th level), you start to perceive familiar happenings such as: a person walking, a bird chirping, the wind blowing. At the next level of relationships (6th level), you see connections between two lower level perceptions such as : a car on the street, people in a car. When you let yourself notice the category level (7th level) groupings of perceptions occur: a flock of birds, cars made by General Motors, pine trees, etc.. Going up a level to the sequence level ( 8th level), you note things such as: the sequence of left, right, left, right; the sequence of the streets that you follow during the walk At the program level (8th level), you become aware of if/then perceptions such as: if it rains, then I take an umbrella on the walk; if it is Wednesday or Saturday then people put out their garbage. At the 10th level of principles, you note the reasons for your taking the walk: to be physically healthy, to meditate, to be social. At the 11th level of systems one notes: taking a walk is consistent with my self image; taking a walk is consistent with my family tradition.
If you actually go on a walk in the neighborhood and attempt to experience the different levels, you might notice that you do not ordinarily verbalize to yourself about the lower level perceptions. You just experience them and feel in contact with your surroundings and the present time. When you start to think about things and are aware at the higher levels of perception, you might notice that you feel as though you have tuned out your surroundings, are "in your head" and are focused on past or future times.
I would like to call the readers attention to some generalizations about the levels of perception just described. As one goes from the lowest level to the highest: (a) the perceptions go from more concrete to more abstract, (b) the time to form perceptions or note changes in perceptions increase, (c) the complexity of the perceptions increase, and (d) the perceptions go from more analogue to more digital.
A person is not aware of all of the levels of perception at a given moment. The law of awareness in Perceptual Control Theory refers to the idea that a person is not aware of levels of perception at or above the highest level at which the person is controlling. For example, if a person is busy at a task which requires relationship level control at the highest, then the person's awareness is limited to levels below the relationship level, as long as the person is task focused. The law of awareness corresponds to the common experience that when a person is concerned about details, they are not aware of the big picture. If the person starts to think about pleasing the researcher or how well they are doing or what they will be doing next, the relationship level is no longer the highest one.
For each discriminable aspect of experience which is controlled, for each perceptual variable, Powers assumes that there is a control system which is doing it. A control system is thought of as a real brain circuit which has an input component, comparator/memory component and output component.
The input component calculates the perception from other, "lower level" perceptions (a perceptual signal is generated). The comparator/memory component calculates the mismatch between the actual and the desired perception contained in memory (an error signal is generated). The output component amplifies the error signal, channels it to the appropriate control systems at lower levels where the error signal results in a set of reference signals for the lower level control systems.
When a control system operates properly: (a) error signals are reduced, (b) the perceptual signal will track the reference signal more or less closely depending on the "gain" of the control system, (b) changes in the perceptual signal produced by disturbances are undone by changes in the perceptual signal produced by the output of the control system; this means that when a perception is controlled, it is the result of environment and person influences, not just environmental factors.
The more important a perception is to a person, the better controlled will that perception be. A person who is really committed to getting a certain result will not tolerate very large deviations from the result. In technical, Perceptual Control Theory language, the "gain" of a control system can very from low (loose control) to high (tight control) . The mechanism by which the gain of a control system is altered is not spelled out in the current version of PCT.
The way that PCT hooks up control systems at different levels is very interesting and important. Note that a control system at a higher level of perception "tells" the control systems at the lower levels what to perceive, not what to do. Each control system at the lower levels is free to achieve its goal specified by "superior" control systems in its own way.
If a human bureaucracy worked this way, then the boss would by saying to each supervisee "Here is what has to be achieved, figure out how to do it" Furthermore, the supervisees would not be questioning/challenging the boss about what the goal should be. In fact, they would be unaware of the higher level goal. Internal conflict would only occur among people of the same level in the bureaucracy. As an example, one boss asked a person to achieve job A and a different boss asked the same person to not achieve job A. The supervisee would attempt both instructions, because challenges/questions are not allowed, and would accomplish neither goal completely. Neither boss would be happy.
A final observation to make about control systems has to do with the adjustments they are always making. In that circumstances may change which can undo the successful efforts a person is currently making to control a perception (disturbances can occur), a person ordinarily has to change actions in order to keep a perception stable at the desired description. These adjustments in action are not a sign of learning but of the ordinary action of a control system at work. The idea that all behavior change does not mean learning, or any of the other causes of behavior change that psychologists are familiar with, takes some adjustment.
In other words, error signals are present in the control systems regulating some important perceptions. The error signals drive body physiology and have two coordinated effects. They prepare the body for the energy demands of some muscular activity and they guide the specific muscular activity which a person actually takes in order to accomplish some goal. Feelings/moods are perceptions a person has of his/her body state. Powers does not provide a list of feelings/moods nor does the current version PCT say much about feelings/moods explicit.
Using PCT concepts, my own thoughts on the topic of feelings are as follows. One can explore a feeling the same way as one would explore any perception in PCT. As a perception, a person can notice feelings at the different levels. At the sensation level, a person knows that they are having a feeling (versus visual, auditory, etc. experience) which can vary in intensity. At the configuration level, a person recognizes that they are having a specific feeling. At the transition level, a person senses changes in a feeling. At the event level, a person can sense that the feeling event happened and then was over. At the relationship level, a person can sense that the feeling relates to other perceptions and how it does. On the category level, a person classifies the feeling as being, for example an angry kind of feeling. On the sequence level one can notice that s/he felt hurt at first then angry. I have found that it is helpful to keep the levels in mind when talking about feelings with people. Even people who have a hard time talking about their feelings can tell you something about the feeling at one of the levels. It is not necessary to have a patient verbally categorize the feelings.
When communicating with another person, the communicator compares the meaning suggested by his/her verbal statement to the intended meaning. A mismatch in the suggested and intended meaning results in the communicator changing something about the verbal statement. If the communicator becomes aware that the other person does not understand, he or she may paraphrase.
The PCT idea of people as perception controlling beings explains the stability one sees in people in spite of changing environments. However, it does not explain what causes a person to learn or develop. This leads to the PCT idea of people as beings who organize/reorganize their nervous system when necessary.
When a person is not satisfying a body need, this is described by saying that an intrinsic error signal exists. The actual body state is not the same as the genetically required state. Only a person can know when intrinsic error signals are present. This is experienced by feelings, for example, hunger, thirst, etc.. The intrinsic error signals can only be reduced by learning and developmental changes in the perceptual control systems which restores the body state to its genetically required state.
Intrinsic error signals automatically trigger a trial-and-error, random-like tissue/biochemical change process called reorganization. This process results in altering the existing "hardware" of selective perceptual control systems within a person. The brain circuits of the error prone perceptual control systems are "rewired".
Awareness is drawn to the control systems which contain error signals and awareness can start the reorganization process. Conflict is a major reason which stops reorganization from working successfully. The reason for this is that awareness is drawn to the wrong places in the organization of control systems. There may be other reasons why the reorganization system does not work properly but these have not been identified by Powers.
Learning is the acquisition of a new control system or the changing of an existing control system through reorganization. Reorganization stops whenever the intrinsic error signals are reduced to satisfactory levels. Development is the acquisition of a new level of perception through reorganization. Thus, in PCT, learning and development are conceptually alike in that they both involve reorganization.
When a person is reorganizing, the person will be unstable in many different ways including cognitions, moods, behaviors. The person will not feel as though the internal changes are being voluntarily produced. People in the middle of reorganization often feel very anxious, stressed and don't know what is happening to them.
The concept of stress, in PCT terms, is describable as chronic error signals or intrinsic error signals. The person's body is aroused but the person is not taking energy spending actions. I have written about stress management approaches from a PCT perspective (Goldstein, 1989).
I have developed an assessment tool called the Life Perception survey to help me quickly identify the problem life areas. I consider this to be a first step towards identifying the out-of-control perceptions. This approach follows directly from the idea that if a person is dissatisfied with a life area then error signals must be present in the control systems involved. The choice of life areas is based on a review of presenting problems upon the initial session.
The progress notes I write after each session makes use of the same categories as are on the Life Perception Survey. In this way, assessment and treatment progress are described in the same terms.
Suppose that the patient chooses to talk about topic B. As the conversation continues, the therapist may notice that topic C is in the background of the conversation. Either the patient will notice this and start talking about topic C or the therapist will point it out. This process of talking and noticing background topics in the conversation continues. The result of this iterative process is to help the patient direct awareness to the right place in the organization of control systems.
The method of levels describes "how to" listen according to PCT. Powers says that what the therapist should listen for is evidence of the next level up. The therapist listens without preconceptions of what that level is, or whether it is conflicted or not. The idea is to follow the patient's lead.
If there is a conflict, it will become evident. The therapist, upon encountering a conflict, just keeps going, if possible. The therapist tries to continue until another level comes into view. The conflict should resolve or begin to resolve when the patient directs awareness to the single control system from which the conflict originates.
An internal conflict exists when a patient wants a perception to be in two incompatible states; the patient wants but doesn't want a certain perception. Internal conflict is the main cause of psychological problems in people Powers hypothesizes. This is because awareness is drawn to the wrong place in the organization of control systems by conflict. Conflict results in a person's awareness being drawn too low in the organization of control systems. The reorganization system is working at too low a level and as a result, the person does not self-regulate.
As indicated above, the key to resolving a conflict according to Powers is to trace the conflict to the single control system from which the conflict originates. A patient has to get above the level of the conflicting control systems and see that the goals for these conflicting control Systems comes from a third control system at a higher level. Upon realizing where the conflict is coming from, the person can make a different choice at the level of the culprit control system which will eliminate the conflict. If a person tries to resolve the conflict at the level of the conflicting control Systems, then the person will not choose wisely. The conflict will remain and continue to plague the patient. On this basis, Powers is against trying to force a patient to take one side of a conflict and ignore the other side.
A second step assessment tool which I have developed is called the Perceptual Control Theory Diagnostic survey (PCTDS). After some therapy discussion has taken place, I have some idea about the aspects of control which seem to be deficient If he is correct about conflict, then therapists using this list should find that conflict is at the top of the list most of the time. And they should find that if they concentrate on working on the conflict issue that the other needed changes will happen as the result of the normal operation of the reorganization system.
The methodology to obtain the hierarchy of perceptions consists of clinical discussions with a person in which the method of levels and Test for the Controlled Perception is employed.
When applying the Test for the Controlled Perception, the therapist will do or say something which is intended to change a perception of the patient which the therapist hypothesizes might be a controlled variable. The therapist does or says something that tends to exaggerate or minimize the perception but not change its nature. If the patient does or says something which "undoes" the impact of the therapist and restores the perception to its pre-disturbance value, then this provides some evidence to believe that the perception may be a controlled perception. Instead of introducing the disturbance, the therapist may simply observe the impact of a naturally occurring disturbance. The idea that a person is a perception controlling being implies that resistance or opposition is a normal phenomenon. A control system resists being pushed away from the reference perception state.
As an alternative approach to finding out a person's hierarchy of perceptions, I have explored Q-Methodology as a way of obtaining higher level perceptions. In one case, I studied the higher level perceptions underlying interpersonal relationships using Q-Methodology (Goldstein, 1989). The general way in which Q-Methodology can be employed to study the hierarchy of perceptions is discussed in a second paper (Goldstein, 1991).
The targets of change in PCTP are the control systems which are not controlling satisfactorily. Powers does not believe that it is possible or advisable to directly intervene to bring about the identified needed changes. However, he agrees that the statements of the Perceptual Control Theory Diagnostic survey can provide a measure of how well reorganization is working to restore control. His attitude is that the therapist has to remove the obstacles which are blocking the reorganization system form working properly. Once the obstacles are removed, the person's own psychological self-healing processes, the Reorganization system, will come into play and bring about the needed changes.
A second major goal is to provide the patient with the PCT concepts of human nature. In this way, the patient is believed to have a better chance of solving his/her own problems in the future.
Powers suggests that therapists have been trying to do too much. We should primarily focus our therapeutic efforts at helping people remove the internal conflicts which stop the reorganization system from bringing about the needed changes in control systems. We should leave to education, politics, religion and family the other kinds of changes which are needed to help a person gain better control of problematic life areas.
I have described what I think PCT implies about the healthy personality (Goldstein, 1990). Powers' view is that we should not be after "superbeings", as perhaps he interpreted my remarks, but ordinary people who can satisfactorily control their lives.
A major role of the therapist is to help direct a person's awareness to the right places in the organization of control systems, in the person's "mind." The therapist help's the person "go-up-a-level" until the person is free to change. The person goes to a point of view in which both sides of the conflict can be viewed and the person can choose new reference signals. As long as the person stays at the level to which conflict attracts awareness, the conflict will not be resolved and will continue. The person will remain stuck.
Once the person is focusing awareness in the right place, the reorganization system takes over from there. Focusing awareness on a control system can start the reorganization process even without any deliberate intention to change it. A common example of this is the disruption of a skilled performance when a person directs awareness to the performance.
The therapist should follow a "hands off" policy when it comes to the reorganization system. This means that the therapist should not directly attempt to change what seems to need changing as suggested by the Perceptual Control Theory Diagnostic survey. The reason is that each person is unique. The therapist could not possible have enough knowledge of the organization of control systems to know what would be the side effects of an attempt to directly change something. Each treatment manipulation has side-effects for the patient. The therapist cannot possible know what the side-effects will be. Furthermore, any efforts to directly change something which a person doesn't want to change will be resisted and unsuccessful.
The point about educating the patient about reorganization is an especially important one. The attitude is communicated that the reorganization system is a friend/self-healing process which is always there when a person's life is out of control. The patient is told that anxious feelings are to be expected during reorganization. The patient may feel worse before s/he feels better and this is the normal course of events in therapy. Many patients have the belief that they will feel immediately better if the therapy is working. We can't rush the Reorganization System. We can direct it to the life areas which are out of control by means of directing awareness.
Powers(l979) has suggested that the building a new control system occurs in a certain sequence. The input function is acquired first. A person gains a new ability to perceive. Then the comparator/memory function is acquired. A person develops a preference for one value of the new perceptual variable. Lastly, the output function is acquired. A person learns how to reduce the error signals using the old control systems or with new skills.
These learning ideas have implications for diagnosis and psychotherapy. The development of a symptom, for example, an obsessive-compulsive symptom, might be expected to proceed from perception to action, from obsession to compulsion. If significant others can intervene early when the symptom is at the input function acquisition stage, then maybe they can shorten the life of the symptom.
The sequence of questioning which PCT therapist Ed Ford(l989) and Reality Therapy practitioners follow when discussing a significant episode can be seen to follow the control system acquisition sequence: What are you experiencing? What do you want to be experiencing? How are you trying to bring about the experiences you desire?
PCTP example 1--If a person is experiencing an internal conflict, then the therapist will use the method of levels with the expectation that the patient will resolve the internal conflict. PCTP example 2--If a person is controlling perception A, and the therapist disturbs perception A in some way, then the patient is expected to say or do something to undo the impact of the therapists actions.
Clinicians working within a general PCT framework will have to fill in this component. For example, I have presented a PCTP method of obtaining and studying a person's self-image (Goldstein, 1990).
PCTP is based on the following propositions: I. Internal conflict is behind most psychological problems.
A. Internal conflict is best resolved by helping a person see both sides of the conflict and making new goal choices.
B. The method of levels is one good way to do this because it takes a person above the level of the conflict.
II. Once the internal conflict is removed, the person's reorganization system will take care of the rest.
A. The perceptions which are out of control will now come under the person's control.
B. The aspects of control which were deficient will correct themselves without an special intervention by the therapist.
A second point is that generalizations should hold in a very high percentage of the cases. Powers own research program shows that this is possible with tracking experiment tasks. Robertson et al. (1987) showed that this is possible in a self-image study.
A third point is that modeling approaches are preferred. At some point in the future one would like to build a model which would incorporate everything we know about the way in which internal conflicts are resolved. When the parameters of the model are estimated for a given person, we would let the model run and the behavior of the model should be the way a particular person solves an internal conflict.
PCTP reminds me of psychoanalytic approaches in a few ways. The idea of conflict as being behind psychological problems is one way. The idea of a person resisting internal changes is a second main way.
PCTP reminds me of Maher's(1983,1989) Experiential Psychotherapy, which falls in the humanistic-existential family, in several ways. The method of levels and the idea of a perceptual hierarchy can be seen in Maher's writings. Maher's idea of experience is very close to Powers' idea of perception. While the idea of resolving internal conflicts is not emphasized directly in Experiential Psychotherapy, I think it is there in the methods and the description of the phenomenal world of patients.
Of course, PCTP reminds me of Reality Therapy. Glasser(1981, 1989), the creator of Reality Therapy, has explicitly said that PCT is the theory behind Reality Therapy. I will refer readers to Ford(1989) for more detailed comments about Reality Therapy versus PCTP. Ford, who is very familiar with Glasser and Reality Therapy from spending years associated with them, does not believe that Glasser really understands PCT.
PCTP is an unusual therapy in that it attempts to derive assessment and treatment practices consistent with a theory about the way the brain works. Recently, I have become aware of a book by Harris(1986) who has attempted to combine recent facts about the way the brain works with psychoanalysis. Harris takes a generalized systems approach when describing the way the brain works. Instead of perceptual levels, his levels are: identity function, ego-function, neuropsychological function, memory-function, neurophysiological function. In addition to this vertical organization of the brain, he describes the lateral organization of the brain. The anatomical and neurotransmitter basis of the lateral organization of the brain are specified. Harris describes three different kinds of reorganization processes: creative process(growth), epigenesis and adaptive process based on the idea of "kindling." Just as in PCTP, conflict or unsolvable problems results in reorganization.
In this brief discussion of other therapy approaches, I have focused on similarities. One possible reader reaction to this might be: PCTP is nothing but etc.. I think that this conclusion would be a mistake. It is only by means of looking through the lens of PCT that one can see the ways that diverse other therapies are similar.
PCTP is not a standard psychotherapy at this point in time. What is needed is for practicing clinicians to flesh out and test the broad outlines which Powers has provided. Powers has provided a neuroscience framework for understanding how people work psychologically and has suggested some implications PCT has for the therapy situation. The main purpose of this paper was to communicate where we stand now.
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Figure 1. PERCEPTUAL CONTROL THEORY DIAGNOSTIC SURVEY .
Figure 2. LIFE PERCEPTION SURVEY .