The Use of Skin Conductance in Treating Anxiety in Biofeedback

By Karissa Rasdal

The Galvanic Skin Response has been used in many different ways.  Early 
research has focused on exosomatically by having external electric currents 
passed through the skin an endosomatically which measure the difference 
between two different electrodes.  In biofeedback it is likely that you would use 
the later of the two methods.  The GSR has many different names, like the 
electrodermal response, skin conductance activity, and skin resistance activity.  
The GSR is measured by hooking electrodes up to the volar surface of the hand 
where there are 2000 sweat glands in every square centimeter.  When the 
gland is on it has low resistance path from the skin.  Under the surface all the 
glands are connected but at the surface they are separate.  When measuring 
the activity you have two electrodes that together with voltage added can give 
you a measure in mho, for conductance and ohm for resistance.   For this form 
of feedback the best form is conductance measures or those in micromho's.  
Conductance measures are those that are on under the skin and increases in a 
linear relationship.  Though this isn't a true measure of the activity it is 
actually a measure of the amount of sweat glands that are turned on.  
The electrical currents are either DC volts, which are supplied in a steady 
current or in AC which I s presented in alternating voltages.  Since sweat 
glands aren't equally distributed there can be problems with readouts, by 
polarizing them.  Silver/silver chloride electrodes can help to minimize this 
(Schwartz, 1995).
It is said that the electrical charge is not only influenced by the person's mood 
at the time but also on immediate emotional reactions.  The charge of a word 
effects a participant physiological response.  The best place to have electrodes 
is on the hand since as mentioned before the vast amount of electrodes that 
are placed there usually between the thumb and the forefinger.  Thus the rise 
and fall measured by the GSR relates to arousal levels.  
One of the first people to use the GSR was Carl G. Jung.  He had participants 
read words and would not their reaction.  The more the word effected the 
participant the higher the GSR measures.  The GSR has been used in lie 
detectors, in the field  of criminology but in psychology it just took a vacation.  
In biofeedback they know that relaxation causes a rise in skin resistance and so 
the more skin resistance you have the more relaxed you are (Shepherd, 
unknown).
Now that we have a little information about the GSR I think that we should 
talk about the other aspect of the paper Anxiety is a negative mood 
characterized by bodily symptoms of tension, and apprehension of the future.  
This can be very difficult to study but you can see some subjective signs like 
fidgeting and looking around, just looking worried.  But can also be something 
that can't be seen by the eye like elevated heart rate, and tension.  It is 
believed that anxiety is a good thing in small amounts but never in large doses.  
Too much anxiety seems to impair the subject and stays with them for long 
periods of time (Barlow, 2002).  
Anxiety is a very common thing for psychologist to deal with.  You would 
probably have at least on in a psychiatrist office each day.  And seems to effect 
the overall quality of life for that person.  Biofeedback includes some form of 
relaxation training that aides the patient in gaining a calmer position.  These 
can be altered to each persons need and the devices used can also be different.  
If a patient is displaying autonomic symptoms then it is likely that they will 
get hooked up to the GSR, Temperature, or heart rate measures.  This along 
with some cognitive interventions that help the negative thoughts the person 
may have about themselves (Brauer, 1999).
An example of a GSR at work would entail hooking a person up to a device, 
usually this is on the fingertips.  This gives you the amount of perspiration on 
the skin.  The more perspiration the more tense you are thought to be.  The 
energy would then be converted into lights or buzzing noises.  When you can 
lower the amount recorded the machine is calibrated so you work harder and 
learn better.  The sessions usually last about 30-60 minutes, with about 15 
sessions.  This should generalize into other areas of their life (Holistics-
online.com, 2002).
In looking for research I came across an interesting proposal of research that is 
going on.  This helps children who have anxiety and needs to address these 
areas. To know how tension states are different from relaxation, to notice when 
the tension starts to rise and change the behavior before it occurs. The final 
thing is to conduct regular activities with less effort.  The proposed treatment 
is to teach 7-10 children various relaxation techniques and then have them see 
how well they mastered them by playing the relax to win game.  The game is a 
two player game where there are two dragons racing, as you get more relaxed 
your dragon goes faster, when in deep relaxation the dragon starts to fly.  This 
group has altered the game so that you race a ghost dragon that is composed of 
the elements of your own personal best.  This will be done in five sessions.  To 
see how will it worked they will take measures before and after sessions, 
monitor the sessions with the GSR and interview both the parents and the 
children after to see how it impacted their life and what the experience was 
like. It will be interesting to find out the results (Sharry, ?)
Along the same lines as this yet uncompleted research is a virtual reality 
measure for adults, working through social phobia.  The client goes through a 
program where there are avatars to talk to.  The first stage is to teach the 
subject a relaxation method like diaphragmatic breathing, and is hooked up to 
the GSR.  This lets the person see that they are calming down.  When the 
subject has some control of this the therapist would take the client to a room 
with 2-D cut outs and talk to the client through these cut outs.  Then the 
client would need to go an use the on line traveler, where they talk to another 
therapist who is logged on in a different level.  Then they would need to take 
some risk where there are other avatars.  If the client is rude the other people 
can mute them or turn their backs on the person.  The next phase would be to 
have them have online chats with a real person and then have them go and 
meet an actual person in real life.  For future use it might be nice to have the 
avatars show a change in color depending on the mood of their body so that 
others using the program might know of the condition of this person and see 
this discomfort (McGehee, 2001).
These were both really interesting to read and I think that they are very useful 
in helping the target group but the proof was not included in the documents 
and we still have to wait to see if what is stated is true.  In fact I could only 
find one article that actually had some kind of results.  Participants were 
measured with the GSR before and after they participated in a stress 
management and relaxation.  The electrodes were placed on the middle 
phalanx of both the forefinger and middle finger unilaterally (right hand only).  
This project lasted for two months.  They were tested 1 hour before stress 
management and then they were given questionnaires, then they were asked to 
practice what they learned until they could be tested again.  The participants 
had improvements in the phasic changes and the tonic levels (Christidis, ?).
Phasic changes are increased rates of conductance and are measured in the 
amount of micromhos above the baseline rate.  The tonic level is the baseline 
level, which tends to stay about the same level at resting (Schwartz, 1995). 
None of the articles really talk about how well biofeedback works when dealing 
with anxiety in a question answer type setting I found one source that said that 
when dealing with anxiety attacks biofeedback doesn't work well.  It appears to 
benefit some people (like 30%) but there is usually a high drop out rate around 
the first four sessions.  But when dealing with phobias using a systematic 
desensitization exercise while hooked up to the GSR can be helpful within 3-
10 sessions (Kuhns, 2002).

References

Barlow, D., Durand, M. (2002).  Abnormal Psychology Third Edition.  
Wadsworth, Canada.

Brauer, A. (1999).  Biofeedback and Anxiety.  Psychiatric Times, 26 (2).

Christidis, D., Kyriakou, E., Vezertzi, M., Komnidis, A., Lazaridis, G. (?).  
Design, Implementation &Standardization of an Electrodermal Resistance 
Biofeedback Device (EDR-BD) and Resulting Changes in Electrodermal 
Activity (EDA) Due to Training in Stress Management Techniques.  Dept. of 
Psychology, Aristotle University of Thessaloniki.
Holistics-online.com (2002).  Biofeedback,ICBS, Inc.

Kuhns, R. (2002) Questions and Answers.  Stress Management Institute.  
http://www.panicbusters.com/FAQ's.html#Is%20useful%20Anxiety%20and 
%20Panic%20Attacks?

McGehee, S. (2001).  Using 3D Virtual Environments to Treat Social Phobia.  
Presented at Banff Center for New Media, September 9. 
 
Schwartz, M. (1995).  Biofeedback.  USA:Guilford Press

Sharry, J. (?).  Relax to Win, clinical evaluation of a biofeedback video game 
designed to teach relaxation skills to children.  
Http://mindgame.mle.ie/clinical.pdf 

Sheperd, P. (?).  The galvanic Skin Response (GSR) Meter.

Copyright © 2003, Dr. John M. Morgan, All rights reserved - This page last edited May 13, 2003
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