HEMOENCEPHALOGRAPHIC (HEG) NEUROFEEDBACK IS
NOW AVAILABLE AT BIOFEEDBACK & ALTERNATIVE MEDICINE CENTERS

INTRODUCTION

Hemoencephalographic (HEG) devices measure and feed back blood flow levels in the brain. When a trainee is made aware of ongoing blood flow levels in a neurofeedback setting, it has been shown that the trainee can use a focused state of concentration and create increases in brain blood flow levels. Although these are relatively new devices, increases in brain blood flow via HEG neurofeedback (HEG NF) have already shown significant clinical benefits, especially in the areas of migraine, depression and ADHD.

Blood is nutritious and healthy for all cell functioning. Increasing blood flow levels where they are needed in the brain is like boosting the octane level of your gasoline at the pump. Repeatedly engaging in HEG NF appears to "exercise" the brain in a unique way with very promising benefits.

EEG neurofeedback (EEG NF) measures brain electrical activity and also increases blood flow at the site trained (which is one of the reasons it works), but it does so indirectly. However, HEG NF increases blood flow more directly since it uses passive infrared (pIR) technology for its measurement.

By its very nature, the measurement of EEG brain electrical activity is considered relatively messy, electronically noisy and more susceptible to artifact (errors) from intruding, non-EEG signals (e.g., muscle tension in the scalp, face, jaws, eyes, eye movements, breathing & EKG heart signals).

On the other hand, pIR HEG measures thermal (e.g., heat) conditions in the brain that are highly correlated with blood flow dynamics and cellular metabolism. In contrast to EEG, pIR HEG measurements are considered clean, electronically quiet and not at all susceptible to the same artifacts as EEG measurements. Special pre-post SPECT imaging techniques verify that blood flow increases do, in fact, occur with HEG NF.

With pIR HEG NF, there are no electrodes, no messy gels and no impedance criteria for skin contact. A simple, dry headset device is used for HEG NF. Again, there are no problems with eye blinking, eye movements, EKG cardiac signals or other muscle artifact, since HEG does not measure electrical activity.

The only drawback is that pIR HEG cannot measure through human hair. As such, the most common three sites used for HEG NF are left forehead (FP1), center forehead (FPz) and right forehead (FP2). These locations wrap around the pre-frontal cortex lobes of the brain.

At first glance, one might conclude that HEG measurements are very limited, since the pre-frontal cortex is only one of six total bilateral lobes in the brain. However, the prefrontal (forehead) lobes mediate some of the most advanced forms of thinking and cognitive activity that we engage in as human beings. In particular, the pre-frontal lobes host the "executive attention networks" that mediate states of sustained focused concentration. The prefrontal lobes are very often a target area for EEG NF in ADHD and other neurobehavioral disorders.

Quantitative EEG (QEEG) topographic brain maps often identify the prefrontal lobes as dysfunctional or even "disconnected" from the rest of the brain through the presence of excessive slow wave activity vs. desirable fast wave activity. Moreover, engagement of the prefrontal lobes is required in order to sustain cognitive activity requiring complex thinking, concentration, emotional tone and general arousal.

Further, activation of the prefrontal lobes appears to be necessary to succeed in EEG NF there and elsewhere on the scalp and exercising the prefrontal cortex seems to improve many auto-regulatory functions of the brain. That may be why HEG NF shows such clinical promise. Finally, since the prefrontal lobes mediate so many complex, auto-regulatory brain functions, they would seem to be the best choice of all brain lobes to be the target for HEG training.