A new discovery, of how we learn during REM and delta wave sleep

on 12 November 2019
redrawing the way the brain works

This is a regurgitated blog from a year or so back but I thought it was worth a rerun or update because of my last blog! So, it's an add on to memory consolidation that occurs during sleep, occurs during REM and NonREM phase 2, and adding NonREM 3 to certain levels of memory and learning . . .

While this detracts little or nothing from the processes of memory consolidation and reconsolidation that occur while we sleep (REM/NonREM 2), scientists have discovered a new fact about slow wave-sleep (aka NonREM phase 3 or Delta wave sleep) and while it remains a very deep sleep state (almost akin to a comatose state), the new discovery is, that deltas wave/slow-wave sleep actually allows the brain to be more selective and effective by numbing down activity in certain aspects of this daily function. Dreaming is a natural part of this process and mostly occurs during REM/NonREM2 sleep but no it is known that NonREM3 plays an integral role in the process also! But some other pretty whacky stuff also happens while we sleep because PGO (Ponto geniculo occipital) waves precipitate REM sleep and once in REM sleep, the locus coereleus almost shuts down its production of norepinephrine. Norepinephrine plays a critical role in the initiation of the fight or flight response, potentially putting the brain in a more relaxed state or maybe, just a less anxious one on those occasions when we have a little too much on our mind; who knows?

It has long puzzled me as to why a client who has little or no awareness of what was said in the hypnotic part of the session, still goes on to make remarkable progress? My theory, of the scientific aspect, of what happens in hypnosis and how it works come from my evolving understanding of this type of research. This is most notable when a client with a fear of flying (that is only related to flying as a conditioned response), loses that fear following hypnosis. The anomaly here is, that during the hypnotic prescription (the words I use), I make no mention of anything related to aviation in general or flying specifically and if I was to talk to them in conscious mode (saying those words), they would still have the fear! So, very clearly a message, hypnotically delivered during dream/sleep states, is processed by the brain and this facilitates memory consolidation and/or reconsolidation. If memory is changed, then it's associated behaviour/response is also changed. 

The only thing that has changed from my previously help view of how this process evolves is, that delta waves and their associated slow-wave/deep sleep states are an integral part of this whole process and will be a part of the hypnotic session and the closely followed sleep states later that day! However, the word evolve gives us some important information to consider and this is because fear is a survival mechanism and the brain does not always let go of these processes easily or lightly; hence why multiple sessions are usually required to effect a permanent cure?

That hypnosis works is well documented but it's a little too random for the scientific community to adopt. And to be fair to them, it does work better for some, than for others. My theory, as mentioned above, is, that if a client comes into therapy with a problem (not just a flying one) and a few sessions later, no longer has that problem, then hypnosis-therapy is likely to be deserving of some recognition for that transition (not discounting the client's involvement). Because of the frequency of this type of therapeutic anomaly, I began to look for an explanation as to why and how this seemingly strange hypno-therapeutic transition occurs and when I discovered that PGO waves respond to auditory stimulation, I thought; this has to be it! The auditory stimulation that the PGO waves respond to, in this context, is the hypnotist's voice (ME)! While I was, in an instant, robbed of the long-held view (by some hypnotherapists), that I possessed strange esoteric powers, it was an easy trade-off because it allowed me to explore new ideas and theories that could enhance my hypnotic work with clients!

So, during the conscious part of the session, we are testing theories, challenging assumptions, thoughts, beliefs etc. and therapeutic interventions (psychotherapy) are posited for consideration. Also, some questions are posed which, most likely, the client would not know the answer to because the drivers of the thought, feeling or behaviour are subconscious in nature. Of course, they often give an answer but very often the conscious answers we give to something (relative to the reasons for therapy) are merely the thing that makes the most sense. And that is often all we need because we have to make sense of everything. By the nature of the way the brain and mind work, we are only ever aware of the result of our neural processes, not the processing itself. So, these questions, theories and assumptions, relative to the solution we seek, are then fed back into the brain, be it directly or through metaphor, through the process of trance induction and deepening. It is this intricate process of trance induction, deepening that elicits the cycle of REM sleep (theta brain waves) and PGO waves thus creating a cycle of suggestion, learning and consolidation (maybe some reconsolidation too). This is akin to rewiring/rewriting the code of the neural networks that ultimately allows the neurons, networks and memories to express themselves in the new, wanted, way!


My objective here is to help people understand how and why we become illogically trapped into emotional experiences that may actually be happening but for reasons different to which we would imagine! If you want to know more about how Hypnotherapy why not make an appointment for a Free Consultation?


The Research: 

Led by Philippe Peigneux, ULB Neuroscience Institute, a group of researchers found that our learning capabilities are limited during slow-wave sleep. Using magnetoencephalography (MEG), they showed that while our brain is still able to perceive sounds during sleep, it is unable to group these sounds according to their organisation in a sequence.

Hypnopedia, or the ability to learn during sleep, was popularized in the '60s, with for example the dystopia Brave New World by Aldous Huxley, in which individuals are conditioned to their future tasks during sleep. This concept has been progressively abandoned due to a lack of reliable scientific evidence supporting in-sleep learning abilities.


A study published this August 6 in the journal Scientific Reports by researchers from the ULB Neuroscience Institute (UNI) shows that while our brain is able to continue perceiving sounds during sleep like when awake, the ability to group these sounds according to their organization in a sequence is only present at wakefulness, and completely disappears during sleep.

Juliane Farthouat, while a Research Fellow of the FNRS under the direction of Philippe Peigneux, professor at the Faculty of Psychological Science and Education at Université Libre de Bruxelles, ULB, used magnetoencephalography (MEG) to record the cerebral activity mirroring the statistical learning of series of sounds, both during slow-wave sleep (a part of sleep during which brain activity is highly synchronized) and during wakefulness.




The results of this study suggest intrinsic limitations in de novo learning during slow-wave sleep, that might confine the sleeping brain's learning capabilities to simple, elementary associations.

Story Source:

Materials provided by Université Libre de BruxellesNote: Content may be edited for style and length.

Journal Reference:

  1. Juliane Farthouat, Anne Atas, Vincent Wens, Xavier De Tiege, Philippe Peigneux. Lack of frequency-tagged magnetic responses suggests statistical regularities remain undetected during NREM sleepScientific Reports, 2018; 8 (1) DOI: 10.1038/s41598-018-30105-5