Infra slow fluctuations in the brain electric potentials 

Implications for health and neuromodulation methods

There is a growing interest in slow rhythms  of  the human and animal brain and their role in the brain self-regulation. Specicically slow rhtythms inlude slow cortical potential, infra-slow fluctualtions and circadian rhythms. 

The time scales of these fluctuations form a continuum from seconds to tens and hundreds of seconds corresponding to slow (0.1–1 Hz), infra-slow (0.01–0.1 Hz), and “ultradian” (b0.01 Hz) (Palva, J. M., and Palva, S. (2012).

Recently our senior scientific adviser

Prof. Yury Kropotov

published an article in the 

Frontiers in Human Neuroscience  journal with title : 

"The enigma of infra-slow fluctuations in the human EEG"

In this article  he covers Hypothesis and theory of ILFs and decribes many aspects of the of ISF including the following:

•Spontaneous Infra-Slow Fluctuations (ISFs) of the human EEG (EEG-ISFs) were discovered 60 years ago when appropriate amplifiers for their recordings were designed.  To avoid skin-related artifacts the recording of EEG-ISFs requiredpuncturing the skin under the electrode. 

•In the beginning of the 21^st  century the interest in EEG-ISFs was renewed with the appearance of commercially available DC-coupled amplified and by observation of ISFs of the blood oxygen level–dependent (BOLD) functional magnetic resonance imaging signal at a similar frequency.

•The independent components of irregular EEG-ISFs were shown to correlate with BOLD signals which in turn were driven by changes in arousal level measured by GSR, pupil size and HRV. 

•There is no consensus regarding the temporal organization of EEG-ISFs: some studies emphasize the absence of peaks on EEG-ISFs spectra, some studies report prominent oscillations with frequency around 0.1 Hz or 0.02 Hz, while some emphasize  multiple discrete infraslowoscillations. 

•No studies used parameters of EEG-ISFs as neuromarkers to discriminate psychiatric patients from healthy controls.  Finally, a set of working hypotheses is suggested that must be tested in future research to solve the enigma of EEG-ISFs.

Prof. Juri Kropotov agreed to provide a 2-hour lecture/ webinar

Enigma of Infra Slow Fluctuations in the Brain

where he explains neurophysiology of the Slow Brain Potential. 

The recording  of the lecture is available for attendies of our FREE WEBINAR