«Хорошая» и «плохая» тета

Дуглас Дейли рассказывает о разнице между хорошей (синхронизированной) и плохой тетой.
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I have enjoyed this discussion which has gone from the role of Pz (the precuneus region) in PTSD to the idea of "whole brain training".

In my opinion, nothing illustrates the importance of whole brain training more than the recent discoveries of the eminent WJ Freeman at Berkeley. He explained why the crucial phenomenon of broad-band global synchrony was missed for 80 years. Here is a brief quote from his fascinating 2009 study.

"Episodic global phase synchrony is identified in background EEG, in all pass-bands from theta to epsilon." "...long-range phase synchrony really is a hallmark of consciousness... Our results confirm this prediction, and suggest that consciousness may involve not only gamma frequencies, but the whole range from theta to epsilon." [1]

This broad-band synchrony is so crucial that if gamma lags by as much as one cycle (1/40th second or less) in its relationship to theta, then long term synaptic potentiation and learning can not take place, much to the consternation of our clients and ourselves [2,3,4,5,6,7,8,9].

Please glance at these last 8 references. Most of them involve the phase synchronization of gamma with theta (not alpha). In my opinion, NFB is being weighed down by the failure to distinguish between what I call "good theta" and "bad theta". Gamma can synchronize with "good theta". Bad theta is.... well... not optimal ! Let me explain.

What I call "good theta" is also known as "fronto-midline theta", "FmTheta", and the Ciganek rhythm. It is synchronous and looks like a slower version of well-formed eyes closed alpha. It is associated with decreased neuroticism, increased extroversion, increased autonomic and immune control, reduced anxiety, and reduction of excess beta activity [10,11,12,13,14]. Gamma can ONLY synchronize with synchronous theta, not with polymorphic (unsynchronized) theta.

"Bad" theta is also called polymorphic theta. It is associated with encephalopathy, ischemia, and intoxication [15]. Given that encephalopathic tauopathies are seen both in the elderly with Alzheimer's disease, and the young with autism spectrum disorder, and given that most of us are probably somewhere between those two age extremes, I find myself very interested in this distinction.

So, I wonder... how often might practitioners struggle to reduce what is, in fact, synchronous theta, and interfere with gamma nesting?

It is my hope that we can move beyond training amplitude at a single site ("location, location, location") and move toward whole brain communication (maybe it is all about timing, timing, timing).

Before we had neurons we had glial cells. Before we had glia we had microtubules. At that earliest time, when we performed the most intelligent human feat by creating a midline, and then limb buds, did we have mind? I think so. And I think it is correct to appeal to that mind to continue to bring neurodevelopment to its maximal fruition. This may best be done by an appeal to global broad-band synchrony. How could such global synchrony even be possible? I don't know. But researches did just discover (2010) something in the brain they call "tunneling nanotubules" and "Roamer type volume transmission". [16]

So, to get from the concept of whole brain training to the relationship between alterations at Pz and PTSD, I will quote a recent article. This article, in my opinion, suggests that it is the relationship between Pz and the remainder of the brain that is important. Any treatment aimed at Pz that does not enable it to participate in network functions, may result in unexpected consequences. ("PCC" in the quote below refers to posterior cingulate cortex, roughly in the region of the precuneus and Pz).

"Spontaneous activity in the default network during rest, as measured using PCC correlations, is altered in patients with PTSD. ...In this patient population, the observed alterations may be associated with the disturbances in self-referential processing often observed in patients with chronic PTSD related to early-life trauma". [17]

[1] Pockett S, et al (2009) - EEG synchrony during a perceptual-cognitive task - Widespread phase synchrony at all frequencies, Clinical Neurophysiology 120 (2009) 695-708.
[2] Keizer AW, et al (2010) - The effect of gamma enhancing neurofeedback on the control of feature bindings and intelligence measures. International Journal of Psychophysiology 75 (2010) 25-32
[3] Steinvorth S, et al (2010) - Human entorhinal gamma and theta oscillations selective for remote autobiographical memory. Hippocampus 20:166-173(2010).
[4] Canolty RT, et al (2006) - High gamma power is phase-locked to theta oscillations in human neocortex. Science 15 September 2006 Vol. 313
[5] Babiloni C, et al (2004) - Synchronization of gamma oscillations increases functional connectivity of human hippocampus & inferior-middle temporal cortex during repetitive visuomotor events. European Journal of Neuroscience, Vol 19, pp. 3088-3098, 2004.
[6] Haig AR, et al (2000) - Synchronous cortical gamma-band activity in task-relevant cognition. Neuroreport, Vol 11, No 4, 20 March 2000. pp 669-675.
[7] Miltner WHR, et al (1999) - Coherence of gamma-band EEG activity as a basis for associative learning. Nature, Vol 397, 4 February 1999.
[8] Schack B, et al (2002) - Phase-coupling of theta-gamma EEG rhythms during short-term memory processing. International Journal of Psychophysiology 44 (2002) 143-163.
[9] von Stein A, et al (2000) - Different frequencies for different scales of cortical integration - From local gamma to long range alpha-theta synchronization. International Journal of Psychophysiology 38 (2000) 301-313.
[10] Asada H, et al (1999) - Frontal midline theta rhythms reflect alternative activation of prefrontal cortex and anterior cingulate cortex in humans. Neuroscience Letters 274 (1999) 29-32
[11] Mizuki Y, Kajimura N, Nishikori S, Imaizumi J, Yamada M. Appearance of frontal midline theta rhythm and personality traits. Folia Psychiatr Neurol Jpn. 1984;38(4):451-8
[12] Mizuki Y, Hashimoto M, Tanaka T, Inanaga K, Tanaka M. A new physiological tool for assessing anxiolytic effects in humans: frontal midline theta activity. Psychopharmacology (Berl). 1983;80(4):311-4.
[13] Aftanas LI, Golocheikine SA. Human anterior and frontal midline theta and lower alpha reflect emotionally positive state and internalized attention: high-resolution EEG investigation of meditation. Neurosci Lett. 2001 Sep 7;310(1):57-60.
[14] Dietl T, et al (1999) - Orienting response and frontal midline theta activity - A somatosensory spectral perturbation study, Clinical Neurophysiology 110 (1999) 1204-1209
[15] Stern JM & Engle J 2005) - Atlas of EEG Patterns. Lippincott Williams & Wilkins. p 273.
[16] Agnati LF, et al (2010) - Understanding wiring and volume transmission. Brain Research Reviews 64(2010) 137-159.
[17] Bluhm RL, et al (2009) - Alterations in default network connectivity in posttraumatic stress disorder related to early-life trauma. Journal of Psychiatry and Neuroscience 2009; 34(3).

«Хорошая» и «плохая» тета

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