What is biofeedback?
Biofeedback is today a well represented and scientifically acknowledged field of studies. The biofeedback technology has found a wide range of applications in the therapy of psychosomatic, psychic and neurological problems. Also it has been successfully applied in stress management and sport training programs.
There are many definitions of biofeedback and several theoretical approaches.
The literature list about biofeedback runs into thousands of publications.
Here are some modern definitions:
“Biofeedback can be defined as the use of monitoring instruments (usually electrical) to detect and amplify internal physiologic process within the body, in order to make this ordinary unavailable internal information available to the individual and literally fed it back to him in some form” (Birk, L. 1973, Biofeedback: Behavioural medicine. New York: Grune & Stratton)
“Biofeedback may be defined as the technique of using equipment (usually electronic) to reveal to human beings some of their internal physiological events, normal and abnormal, in the form of visual and auditory signals in order to teach them to manipulate these otherwise involuntary or unfelt events by manipulating and displayed signals” (Basmajian, J.V. (Ed.), 1979, Biofeedback: Principles and practice for clinicians. Baltimore: Williams & Wilkins)
“A tentative definition is that biofeedback is the process or technique for learning voluntary control over automatically, reflexively regulated body functions” (Brown, B. 1977, Stress and the art of biofeedback. New York: Harper and Row)
“Biofeedback training is a tool for learning psychosomatic self-regulation” (Green, E., & Green, A. 1977, Beyond biofeedback. New York: Delta)
Three main theoretical models underlying these definitions are:
- Learning theory model – Biofeedback is instrumental conditioning of neuromuscular and autonomic activity using the fed in signals as positive reinforcement.
- Cybernetic model – Biofeedback as the external feedback loop of physiological signals makes possible for a motivated person to make appropriate inner adjustments.
- Stress management model – Biofeedback is used as a tool for stress reduction
All these definitions and models have in common the therapeutic aspect of biofeedback.
Another branch of biofeedback technology has developed parallel to the clinical applications and is connected to the “self-awareness” ideas. Here is not the therapy of some “abnormal” human condition the main goal of biofeedback application, but the achievement and control of “expanded” states of consciousness.
One of the pioneers of these ideas, C. Maxwell Cade, formulated this in the following way:
“Essentially, biofeedback is a new way of learning about ourselves, or a way of relearning, or realizing for the first time, what the body already knows – how to act, how to feel, even how to heal – if we listen to it. With biofeedback instruments and techniques, the art of listening to internal cues can be restored, or established. Since one can not control that of which one is unaware, biofeedback can be said to provide the means to become aware – acutely aware – of ourselves, and thereby to gain the possibility of self-control. […] The chief characteristic of the biofeedback process classifies it as a cognitive process; this characteristic is awareness of the relationship between mental activity and the feedback signal initiated by the bodily activity which is being learned.” (C. Maxwell Cade & Nona Coxhead, 1979, The awakened Mind: Biofeedback and the Development of Higher States of Awareness. Wildwood House Limited)
Any possible method for gaining the signals coming from the human body can be theoretically used for biofeedback. Some of the most
applicable methods today are:
- Skin Resistance – Terms: galvanic skin response (GSR), electrodermal activity (EDA) consisting of electrodermal response (EDR) and electrodermal level (EDL), skin conductance activity (SCA) and its components SCR and SCL, skin resistance activity (SRA) and the specific parts SRR and SRL. Two electrodes are placed over the sweat glands* of the skin, and a small voltage is applied to the electrodes, a circuit is created, and an electric current in microampere range will flow.
- Electromyography – EMG. It measures the electrical correlate of the muscle contraction in the micro volt range.
- Respiratory Feedback – RESP. A belt or a distance sensor over a chest or temperature sensor in front of the nose / mouth is monitoring the respiration process.
- Peripheral Temperature and Finger Phototransmission as correlates of peripheral vasoconstriction.
- Heart Rate – HR / HRV. The heart rate measured by an ECG system or finger / ear phototransmission sensor unit.
- Electroencephalogram – EEG. Small electrical changes in the micro volt range are being picked up by a system of electrodes fixed on the surface of the head. For biofeedback application the “brain waves” are being analyzed for their local distribution in the left, right hemisphere and their spectral (frequency) distribution.
*A gland of the skin that secretes perspiration and opens by a minute pore in the skin
Other, more exotic forms of biofeedback like MEG or light evoked ultra-weak photoluminescence, are very promising but still in the stage of research and very costly.
Skin resistance or applying the historical term, galvanic skin response (GSR), is one of the easiest and robust methods for biofeedback. Although it is simple in application it delivers quite complex data from which many psychophysiological parameters can be derived.
History of GSR
It is difficult to fix the point when biofeedback era began. Some refer to Galvani’s discovery of the electrical process in nerve and muscle action, which quickly stimulated research into the medical applications of the electricity.
By 1840, it was widely believed that electrical process over the body provided a basis for explaining disease and generating diagnoses and therapies. By 1870 sophisticated instrumentation and procedures had been developed as part of electrophysiological research methodology. Sudden changes in skin resistance were seen as a source of artifact at this time and even special instruments were build to control or suppress these changes.
First in 1879, Romain Vigouroux measured skin resistance in several cases of hysterical anesthesia.
In 1888, Chatles Fere, a colleague of Vigouroux, noted changes in skin resistance after physical stimulation.
In 1915 this process was called galvanic skin response (GSR) and Fere’s study was referred to as the first statement of an arousal theory.
Several years earlier, a German researcher, Hermann, found out that GSR is connected to sweat gland activity, thus giving a physiological explanation for the phenomenon.
In 1889, the Russian investigator, Ivan Tarchanov, was able to show that mental activity could cause changes in GSR. The works of Fere and Tarchanov were forgotten for many years.
In 1904 as a Swiss engineer, E. K. Müller, noticed that GSR changed even with regard to psychological events. He passed his observations to the Swiss neurologist Veraguth, who was a friend of Carl G. Jung.
Jung used the GSR in word associations experiments and by 1907 he considered GSR or “psychogalvanic reflex” as a method to objectify unconscious “emotional tones”. He was also the one who brought the ideas of GSR to the United States.
The actual state of the GSR in biofeedback is very well described by Charles J. Peek in one of his standard works:
“This physiological variable has appeared in countless psychological experiments, in clinical practice, in “lie detector” equipment, and even in toys and parlor games. Biofeedback has used it for access to autonomic arousal. Skin resistance is recognized as *distinctively sensitive to transitory emotional states and mental events, while often remaining more or less independent of other biofeedback measures such as muscle tension and skin temperature. It is a complex variable, responsive to a wide range of overt and covert activities and external and internal stimulation. Its responsivity to psychological content in actual or laboratory human situations apparently prompted Barbara Brown (1974) to dub GSR “skin talk.” […] That is, EMG and temperature biofeedback tend not to reflect mental events as quickly or with as much resolution as GSR.” (Charles J. Peek, A Primer of Biofeedback Instrumentation, in Biofeedback: A Practitioner’s Guide by Mark S. Schwarz and Associates, 1995, The Guilford Press N.Y.)
For all this reasons GSR was a perfect method to start with the development of stress management biofeedback software modules: “Mental Games” and “VERIM”.
Biofeedback versus Psychointeractivity
Imagine biofeedback as a mirror in front of a person. The person can see
in the mirror a representation of his psychophysiological parameters,
for example the GSR level.
The mirror is merely a reflecting plane, an algorithm displaying the GSR level in some form, unable to react on its own.
Only the human (and animals?) can react to the displayed information in this setting.
The interaction, or the loop is limited to one way only.
Now, imagine that the mirror becomes a psychointeractive crystal cube.
The GSR of the person is not displayed directly to the person by the cube but is being stored and processed inside to enable a decision what information or action will be displayed as next to the person.
It may be just a linear “mirroring” as in biofeedback but it may also be a quite different, nonlinear reaction; a new scene, a new situation, a new game.
This will invoke a reaction in the psychological system of the person, which will show itself in the GSR. The GSR is being monitored by the cube.
In this sense our psychointeractive cube knows the actual arousal state of the user with regard to its actions and now two way interaction is possible.
The idea of psychointeractivity is not only restricted to human – computer interface but can be also used for human – human interaction via psychophysiological parameters.
We call it group psychointeractivity and were granted an European patent in 2004.
This idea of networking implemented in VERIM ProNet is highly acknowledged in team sports, HR and education.
An interesting aspect about the psychophysiological signals is that they are often not conscious and are not controlled by the user.
This gives the psychointeractive system a communicative advantage.
Computer as Inner Theater
In her book “Computer as Theatre”, Brenda Laurel writes:
“The shape of a play can be visualized in terms of the pattern of emotional tension created in its audience. Typically, tension rises during the course of a play until the climax of the action and falls thereafter. […] The climax of a play is the moment at which one line of probability becomes necessity, and all competing lines of probability are eliminated. Hence the climax is not only an emotional peak but informational as well. In fact, the implicit assumption in this analysis is that there is a direct relationship between what we know about the action and how we feel about it. The manipulation of information establishes causality and probability, and it is the basis of such audience responses as suspense, surprise, and catharsis.” (Brenda Laurel, 1993, Computers as Theatre, Addison Wesley)
This is precisely the way a standard play is build. Brenda Laurel uses her knowledge of theatre as a basis for developing multimedia productions.
Now, how can data relating to the emotional tension the observer is experiencing according to the play’s development, change the play itself?
Can you think of a film changing its scenes, action and story depending on the emotions it invokes in you?
What about a multimedia adventure game branching into multiple paths where each “node” scene evaluates your mental, conscious reactions and your mental, emotional actions of which you are not aware?
These are simple “topological” elements which can be used for psychointeractive storyboard.
Using just the first, the basic element called “Differential Decision Point” will expand the story like this:
Strangely enough the psychointeractive story-boards resemble the reality at quantum level creating multiverses of possible “stories” where each node represents a “decision point”.
First, the decision is an unconscious psychophysiological reaction, until we learn how our mind works and are able to consciously choose how to react.
If we even go further and take into consideration the simulated reality or simulation hypothesis things get even more wired.
©2001-2016 Slawinski A.