What is a Neurofeedback Machine?

In neurofeedback therapy, brainwave activity is measured with a precision instrument, and a frequency is “fed back” to the brain to facilitate positive changes. Often, this information is displayed to the participant in the form of sounds, images, or something like a video game, in which the display changes based on the brainwave frequency. This allows people to become “trained” in self-regulating their own brainwave frequencies through trial-and-error and repeated practice. There are three main types of detector used in neurofeedback therapy: the electroencephalogram (EEG), the hemoencephalogram (HEG), and the low energy neurofeedback system (LENS) 

The EEG: A Neurofeedback Machine That Measures Brainwave Activity 

The most commonly used device in neurofeedback therapy is an EEG. Through an EEG, electrodes are placed at strategic locations on the scalp, where they detect brainwave frequencies. This is possible because neurons, or brain cells, are “polarized,” meaning they carry an electrical charge. The nervous system works via electrical activity, known as “action potentials,” and this is how information is carried through the nerves and brain.

An EEG readout takes the form of a graph that shows wavelike forms. This graph reflects oscillating electrical frequencies, which are indicative of the type and location of neural activity happening inside the brain.

Some brainwaves have distinctive patterns, and are associated with certain types of activity. “Alpha” rhythms and “theta” rhythms, for example, are associated with relaxation, whereas “beta” rhythms are associated with conscious mental focus and concentration. An EEG machine can be used to measure and identify these rhythms, and in neurofeedback therapy, this information is used to teach people to change their brainwaves at will. 

The HEG: A Neurofeedback Machine that Measures Blood Flow in the Brain 

Another type of neurofeedback machine, less commonly used than the EEG, is the HEG, or “hemoencephalogram.” An HEG machine uses infrared sensing to detect blood flow within the brain. Measuring where in the brain blood is flowing, and how oxygenated the blood is, can indicate what regions of the brain are active, which gives an idea as to what neurological and mental processes are occurring. There are two main types of HEG neurofeedback:

·         Near Infrared Sensing (NIR), which measures local changes in oxygenation of the blood

·         Passive Infrared Sensing (PIR), which measures the amount of heat being produced in a region of the brain

Both of these measures are reflections of where blood is flowing within the brain, which can indicate the source of the patient’s problems. Thus just like with EEG data, HEG data can be used in neurofeedback therapy to inform individuals of their own mental functioning. 

The LENS: A Commonly Used Neurofeedback Machine 

The Low Energy Neurofeedback System (LENS), developed in 1992 by Dr. Len Ochs, is yet another frequently used neurofeedback machine. In the LENS system, an EEG machine is connected to computer software. An electrical frequency, specifically a radio frequency, is then fed back to the brain in order to stimulate EEG activity. LENS participants report feelings of calm and increased mental clarity. LENS software uses games as a framework to display information to participants about changes in their brainwave frequencies. 

Neurofeedback Machine