Articles from Focused Technology Newsletter 9/93
EEG And Autonomic Feedback
As a biofeedback practitioner I've learned to gather as much information as possible to understand the client. Even physiologic responses not used as feedback are pertinent. Our physiologic systems do not work independent of each other. They are in a constant responsive interplay. When we record these responses for later playback, we begin to understand more fully the client's quality of learning.
It is important to remember any form of biofeedback challenges the client's patterns. This challenge often is a stressor. A flattened or excessively high EDR or a drop in temperature usually indicates a distress response. Having the autonomic data available helps us to discriminate the amount of distress and what system is stressed during the EEG feedback session.
One of the features of the F1000 is the ability to unobtrusively monitor the temperature and EDR during the EEG session. After the session you have this data available to provide a more comprehensive picture of the client's responses. You may also monitor these autonomic systems during the EEG session. If you observe a distress response, such as a drop in peripheral hand temperature, you can easily shift from EEG to temperature feedback.
Autonomic distress has several possible interpretations. The drop in peripheral hand temperature may be associated with performance, trying too hard to succeed, attempting to comprehend what is happening or possibly mental confusion with the task. Too much mental effort is taking place.
EDR is an indication of involvement, particularly, emotional involvement. A high reading may indicate excessive excitement. Often this is indicating anxiety with the challenge of new learning. This may affect the amount of retention or how the client learns during the feedback session.
More dramatically the flat EDR may signal shutting down involvement or dissociation. The client is in a bind. He is simultaneously experiencing the feedback challenge and closing down his involvement. A flat EDR may be an indication of a life style which may impact the results. It is like the quiet before the storm. A client can only sustain "composure" or hold himself together for a limited time with the challenge. Eventually the tension of the conflict has to be released or suffer effects from long term containment. Sometimes the client's release may appear as an abreaction.
The autonomic response may be a confirmation of the client's progress. For instance, Peniston's protocol begins with peripheral hand warming. By collecting thermal data during the EEG neurofeedback session you will have input about the client's ability to sustain the thermal training. Data about the client's autonomic responses allows us to be more effective in providing appropriate strategies for them as they progress in their EEG training.
12/28/03 update: Autonomic feedback was invaluable in working with Mary after her stroke.
Protecting the Temperature Cable
The fast response of the F1000 temperature is due in part to the way the probe and cable are designed. The metal tube provides good thermal conduction of heat into the thermistor while small wire in the cable reduces heat conduction to/from the surrounding environment. These requirements, unfortunately, make the cable more vulnerable to damage.
We suggest using only paper tape to attach the probe. More aggressive adhesive tapes will not easily release if the subject decides to remove the probe by pulling on the cable. We often route the cable up the arm to the preamp box which is attached to the back of the client chair with velcro. This provides maximum protection in cases where an abreaction occurs.
The thermistor probe should not be inserted in the mouth or immersed in a liquid. The tip can be safely wiped with alcohol if it needs cleaning.