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November 18, 2009

Handwarming from the Inside out; Thermal / Temperature Biofeedback

By Rob Kall

Have you warmed your hands lately? How about your feet? Thousands of people do it every day and they don't do it by putting their hands or feet under warm running water or by holding warm clothes, straight out of the dryer. They do it from the inside out. Why would they do it? To help symptoms of stress, anxiety, headache, high blood pressure, Raynauds, diabetes, arthritis and more.


Have you warmed your hands lately? How about your feet?
Thousands of people do it every day and they don't do it by putting their hands or feet under warm running water or by holding warm clothes, straight out of the dryer. They do it from the inside out.

Why would they do it?

Some have headaches, or stress disorders, anxiety or have an illness that's aggravated or set off by stress and tension. Some, the ones who warm their feet, in particular, have diabetes induced circulatory problems, or high blood pressure

These people are using the simplest, most inexpensive and accessible biofeedback technology available-- thermal or temperature biofeedback-- to warm their hands and feet.

Thermal biofeedback is based on a simple physiological fact. When you relax, when you turn down your stress response, all other things being equal, your hands warm up.

This understanding, that relaxation warms the hands and feet and stress, anxiety and fear cool them is not new. You've probably used or know phrases that characterize it, like,

"Cold hands, warm heart," for someone who is nervous,
"cold feet," for someone who is scared or experiencing anxiety.
"hot head" for someone easily upset or angered

The idea was described by writers and poets literally hundreds of years ago.

Thomas Fuller, in his book Gnomologia, wrote, over 250 years ago,
"Head and feet keep warm, the rest will take no harm."

A few hundred years earlier, Shakespeare described the phenomenon at least twice in his writings:
"Why does my blood thus muster to my heart,
And dispossessing all my other parts
Of necessary fitness?"

"The veins unfill'd, our blood is cold,
and then we put upon the morning,
are unapt to give or to forgive;
but when we have stuffed these pipes
and these conveyances of our blood with wine and feeding,
we have suppler souls than in our priest-like fasts:
Therefore, I'll watch him till he be dieted to my request,
and then I'll set upon him."

These are all phrases that describe the temper-temperature connection. Stress, anger, anxiety, fear all set off the stress response. But it wasn't until the last century that scientists understood the process-- that the stress nervous system causes blood vessels in the hands and feet to constrict, cutting circulation and cooling the extremities. The cardiovascular component includes rapid heart beats, increased blood pressure and shifting the blood flow from the skin to vital organs and muscles braced in preparation for fight or flight.

Here's how the Cold Hands Stress Response Works
The muscles encircling the walls of blood vessels in the skin tighten up, narrowing the lumen, or passageway of the blood vessels, decreasing their diameter. This cuts the blood flow (vasoconstriction) and causes the skin in the hands and feet to cool.

When the blood is "squeezed" out of these blood vessels in the skin, it has to go somewhere. It ends up raising blood pressure, going to the head and contributing to migraine headaches when the blood starts pounding in the braining, causing flushing or blushing. If a person suffers with diabetes, then stress-caused constriction of blood flow in the feet can worsen already problematic circulation or peripheral vascular disease which can cause pain, intermittent claudication and worse. Thermal biofeedback for the feet in patients with diabetes has helped enable them to walk further. In children with labile diabetes it has helped them to stabilize insulin and sugar.

The stress nervous system can also decrease blood flow to the gut, which can cause irregularity in the normal motions of the bowel muscles. Fluid absorption can decrease. This can set off symptoms of irritable bowel or colitis-- diarrhea or constipation. Stress nervous system induced reduced blood flow can also set off or aggravate menstrual cramps or hot flashes, both highly vascularly related problems. Studies have also shown it can help symptoms associated with arthritis, Raynauds and chronic pain.

High blood pressure or essential hypertension can be caused by the "cold hands stress response," because the same amount of blood is forced into a smaller volume. Diuretics and beta blocker medications both work to decrease the pressure by lowering the volume of fluid-- diuretics by causing fluid excretion, beta blockers by decreasing peripheral resistance. That means relaxing the blood vessels in the extremities so blood can be spread to a larger volume.

By touching your fingers, which react the most dramatically to stress induced constriction, to your lips, you can detect temperature changes as small as three degrees fahrenheit. Temperature feedback uses precision thermometers to feed back information about tiny changes in finger temperature. Biofeedback instruments enable you to detect changes from half a degree to one hundredth of a degree fahrenheit. The added sensitivity makes voluntary self control of your finger temperature not only possible, but probably the easiest form of biofeedback-- and certainly the least costly.

The Discovery of the Power of Thermal Biofeedback
At the Menninger Foundation, in Topeka Kansas, in the mid 1960's, researchers were studying the effects of Autogenic Training, a relaxation technique developed in Europe, based on psychophysiological responses to hypnotic suggestion imagery, which has had thousands of studies published attesting to its efficacy. The researchers observed a subject whose finger temperature increased over ten degrees in just a few minutes. After the ten minute session was over, they asked, "What happened?"

The subject replied, "How did you know my migraine headache went away?"

Word of her remarkable headache relief flashed through the Menninger foundation's corridors and the researchers quickly had plenty of Migraine HEadache suffering subjects as volunteers. Since that time, many studies have repeatedly shown that temperature or thermal biofeedback h elps about 85 percent of migraneurs. Joseph Sargent, M.D. and Elmer Green, one of the pioneers of biofeedback, published the first research on this.

Since the Menninger discovery, clinician researchers have found that learning to warm your hands from the inside is one of the easiest self regulation skills. With a precision thermometer you can learn in hours what it took Yogis years of practice in the Himalayas to learn. And thermal voluntary self regulation-- what you learn with thermal or temperature biofeedback-- is a practical skill.

Research has shown that stress causes a one or two degree fahrenheit over a five minute period, sometimes even faster. The old mood ring was based on temperature sensitive liquid crystals that changed temperature in response to changes in finger temperature. The same goes for most stress cards. The ring or card goes through four or five color changes which each represent anywhere from three to five degrees fahrenheit. I invented a precision biofeedback ring, the Bio-Q ring, which detects changes of half a degree fahrenheit across the full range of finger temperature which most people experience in room temperature.

Electronic thermometers can be far more sensitive-- from a tenth to one hundredth of a degree fahrenheit. Another factor in electronic thermal feedback devices is the quality of the temperature sensor-- the thermistor. Better ones are smaller, more sensitive and respond faster. A faster response enhances the biofeedack training experience. Another feature of some thermal biofeedback devices is audio feedback. You can listen to a done which develops a deeper pitch as temperature increases, or which click or beeps slower as hands warm, as an indication of relaxation.

With computerized thermal biofeedback, small, high quality, fast response thermistors are the norm. Then, you get to see graphs on the screen, which show the changes in temperature in real time.

You can learn learn handwarming with biofeedback rather quickly, compared to other biofeedback modalities like EEG, respiration, or heart rate.

The cost for a home trainer can be as little as a few dollars if you use a stress card or Bio-Q ring or band.

Stress Card with 1 degress resolution.

The cost goes up to about $30 for a lower cost digital electronic thermometer with a thermistor and sensitivity designed for biofeedback.

More sophisticated thermal biofeedback stand-alone boxes used to be available from a number of manufacturers. Now, they are only available used, usually for $150 to $500 (new, they sold for $300 to $1000.) Temperature biofeedback software, with hardware starts at a little over $200 and ranges up to thousands of dollars. Used computer systems are available for as low as $300.

computerized thermal biofeedback.

Authors Bio:

One theme has run through my work for the past 40 plus years-- a desire to play a role in waking people up, raising their consciousness and empowering them.
I was the organizer founder of the Winter Brain, Optimal Functioning and Positive Psychology and StoryCon Meetings and president of Futurehealth, Inc., with interests in Positive Psychology as well as being involved in the field of biofeedback/neurofeedback since 1972.
see my more detailed bio, reflecting my work in biofeedback, here.

In 2003 I founded , where I've written over 1800 articles and have published over 100,000 other people's writings, with the goal of raising people's consciousness in political and activist ways.