Infra-Slow Fluctuation Neurofeedback Training

The distinctive impact of ISF neurofeedback resides in the training of the “ISF band” which is below 1 Hertz. The physiological changes and regulation of the autonomic nervous system that we see in ISF training occur simply because those are the functions that are coordinated by that band. ISF is considered an ‘organizing’ rhythm; promoting fluid and timely brain function. In concept, when we train the ISF signal, we are supporting clients in their ability to globally regulate their systems. Read More →

Researchers have proposed that the ISF is generated from two possible sources:

• Neuronal activity (electrical or mechanical stimulation, neurotransmitters, neuronal activity). Neuronal activity results in decreased oxygen. This stimulates calcium waves.
• Spontaneous activity (astrocyte clock gene expression results in calcium waves).

The production of calcium waves induces oscillation in a type of glial cell called ‘astrocytes.’ This astrocytic oscillation triggers burst firing of the neurons, which causes frequencies to actively connect or synchronize and establish cross-frequency coupling. Learn How It Impacts The Brain and Body.

There are two types of ISF training: ISF1 Bipolar and ISF2 xLORETA:

1. ISF1 Bipolar: In ISF bipolar training, the ‘frequency’ is reinforced differently from traditional neurofeedback. Because the ISF is slow, it doesn’t oscillate the same way that Delta to Gamma do. Training the ISF band by providing feedback as a ‘mirror’ of the ISF wave form – without augmenting or inhibiting amplitude – is the effective method. It is analogous to a room full of tuning forks simultaneously starting to vibrate when one tuning fork is struck. Similarly, the nervous system attempts to synchronize with the movement of the ISF range reflected in the audible tone the client hears from the speakers. By training that ‘organizing rhythm’ we support the client in regulating their autonomic responses which produce the physiological changes associated with ISF training.
   
   
2. ISF2 xLORETA: This form of infraslow neurofeedback training functions similarly to traditional neurofeedback. The protocols reward an increase or decrease in the amplitude of the ISF band, based on the therapy goal of activating or deactivating the given region of the brain. The focus of training are the nodes of autonomic control in the deeper cortex.

In September 2021, Melissa Bekker, Karlien Balt, PriyeshBipath, Joyce Jordaan, and Peet du Toit published “The Effect of Infra-Slow Fluctuation Neurofeedback Training on a Cohort of Insomnia Participants” in NeuroRegulation. The study concluded that, following a series of 10 ISF training sessions, participants presented with an improved neurocognitive state with a decrease in depression, anxiety, and stress. Associated physiological changes included improved core and finger temperature, lower heart rate, and measures of blood pressure. They concluded that ISF Training “should be considered as a viable alternative” to support insomnia symptom management. Read More About The Research