What are the different types of neurofeedback? (continued)

Following on from the previous post, here we will think about another important way in which some styles of neurofeedback are different from each other. This time we will consider the frequency of brainwaves that are focused in on during the neurofeedback training.

Generally, styles of neurofeedback either focus on EEG band training (from about 1Hz to 40Hz) or Infra-Low or Infra-Slow frequency band training (normally below 0.5 Hz, and often much, much, much lower, like even down to 0.00001 mHz).

To understand what the difference is, lets back up a minute and think about an analogy that we can all relate to. Imagine you are sitting by the sea, and you see these ripples on the water:

Each of these ripples probably is only there for half a second or so, they pop up and sink down again rapidly. We could think of these ripples like brainwaves of higher frequencies. If we expand our awareness, though, we can see that there are waves underlying the ripples, larger and slower to move up and down, maybe taking a few seconds to rise and fall.

But that’s not all that’s going on. Even as the waves and the ripples are rising and falling in their own individual rhythm, the sea as a whole is moving towards the land and then away from it over a period of many hours, as the tide comes in and the tide goes out.

And we are not finished yet. Have you heard of a ‘spring tide’? A spring tide is an extreme tide where at high tide the sea comes in further than ever, and at low tide the sea goes further out than ever. Spring tides happen roughly every 2 weeks, at full moon and at new moon. In between when the tide is at its least extreme, it is called a ‘neap tide’. So the magnitude of the tide itself also goes up and down in a rhythm, this time taking days and days.

And all of these rhythms are active simultaneously, layered on top of each other, from the spring/neap tide rhythm that takes days to rise and fall, to the small ripples that rise and fall in a fraction of a second. As you might have guessed the situation with our brainwaves is very similar. We have faster brainwaves, that rise and fall often many times per second. As an example alpha brainwaves are at a frequency of 8-10Hz, which means that they rise and fall 8-10 times per second. Even some of the slowest brainwaves in the conventional EEG band, delta waves which are produced during deep sleep, still rise and fall about once per second (1Hz). But then we also have many layers of brain activity underlying these, including some brainwave frequencies that take minutes or hours to rise and fall, and even some that take days or weeks. It is these slower frequencies that we are talking about when we refer to infra-low or infra-slow frequencies.

So why are we interested in these slower waves of brain activity? It sounds pretty boring and uninteresting, right? Well, it seems that these slower waves of activity are actually very fundamental to the regulation of the whole brain, with some layers of activity likely related to energy/fuel supply to the neurons in the brain. Without energy, no part of your body can function well, so its no surprise that these slower waves of activity are fundamental to stability and good functioning of the brain.

In the early days of neurofeedback, the brainwave frequencies that were measured and displayed as feedback were only the higher frequency (faster) brainwaves. This was partly because the technology was not developed enough to show slower brainwaves with good enough accuracy, but mainly because the importance of the slower brainwaves was not really understood at all in those days.

Sue and Siegfried Othmer, who developed the Othmer method of neurofeedback, discovered over years and years of treating client with neurofeedback that focusing in on infra-low frequencies consistently gave the best, most rapid results and was able to help people with more complex problems or past trauma. This is why the Othmer method of Infra-Low Frequency (ILF) neurofeedback, is the approach that we use at Neurointegra. We train the brain using low frequencies of anything from 0.1mHz to 0.00001mHz. Other styles of neurofeedback will only use the higher frequencies, around 1Hz to 40Hz.