How the Headbands Work

An area of the brain that is more active will give off more heat and have greater blood flow and blood oxygenation than a brain area that is less active. The two HEG headbands take advantage of these facts.

The pIR or passive infrared headband, developed by Jeffey Carmen, measures the infrared temperature at the skull under the headband sensor, an infrared thermometer. It is passive in the same sense that EEG electrodes are. It measures but introduces no signals of its own to the brain. After experimenting with several forehead placements, Carmen now believes pIR HEG training is most effectively done at FPz. You run about 5 minutes of baseline until the temperature stabilizes, then set a threshold and start training.

The nIR or near infrared headband, developed by Hershel Toomin, utilizes the fact that more highly oxygenated blood is redder in color. It sends pulses of red and infrared light through the skull to the cortex beneath. (The skull itself is not opaque but translucent.) By measuring the amount of red compared to infrared light that is reflected back by the cortex to the headband sensor, the headband can indicate how much oxygen there is in the blood. Because the light pulses take battery energy, the nIR headband uses more energy and has a lower battery life than the pIR headband.

The nIR headband can be placed at most locations on the skull. However, at hair covered areas, the hair needs to be parted and this can be a difficult skill to learn. The headband is typically used to train frontal areas.

See detailed instructions on using nIR HEG.

Using HEG

While HEG is not as flexible as EEG, it's advantages are that the sensors are very easy to apply without mess and that artifacts are minimal. Atifacts in EEG data are particularly problematic in frontal areas.

Both HEG systems have been used successfully with conditions that benefit from learning to increase activation of prefrontal areas, which are normally the most active areas of the brain. pIR has been particularly successful with migraines (see sidebar), and nIR was first used with attention issues, but both methods are now used in a wide range of situations. You would not, however, use either method where beta and hibeta levels were high.

That being said, there is not yet definitive information on how large an area of the brain is influenced by nIR or pIR HEG training. Nor are there clear indications for choosing between nIR and pIR.

Examples

Here are a couple of examples of what HEG training can be like, including the Toomin Attention Index:



"... pIR HEG training... involves a type of conscious activity that produces the results.....this conscious activity is maintaining a very active engagement in focusing while staying relaxed and emotionally calm. Unlike a typical relaxation technique, this exercise teaches how to stay calm during active engagement. I've had several reports from clients who say that they can consciously transfer this strategy to every day life. But, after several sessions of training, the transfer is usually more automatic than deliberate."
                                                                                         Fred Bramble



"I have observed that the [nIR] HEG signal drops proportionally with the slightest decrease in attention. In this vein I have designed a BioExplorer function that rewards more constant attention.

"I have made a Attention Index signal diagram for it that works to enhance attention as well as increase blood oxygenation. It uses a media cartoon of a robot climbing stairs to a kid's slide. High marks accrue to him who makes the robot slide to the bottom of the slide and hang there. It's difficult to pay rapt attention to maximize the Attention Index score."                                                                                      Hershel Toomin