The brain puts the memories warehouse in order while we sleep

on 28 December 2020
the association of memory and brainwaves

While we sleep our brain sets about organising and reorganising our memories, a process called sleep-dependent memory (SDM) consolidation (for new long term memories) and SDM reconsolidation (updating current memories). Our life experience is, to a degree, the collateral effect of these processes  .  .  .

Your own personal Filofax; at work as you sleep!

Of course, there's an awful lot more going on while we sleep, e.g. clearing up the clutter, a bit of housekeeping and of course, some filing.

But have you ever wondered why you retain some seemingly irrelevant information and, at the same time, forgot something far more important? Research suggests that there is far more in our heads than we can easily remember. However, often, this is merely a consequence of there not being any connecting/associated stimuli; something to wake up the deep storage box or memory. This is also the very same reason we have random thoughts, for no apparent reason, something stimulated our senses, which then stimulates a memory. For example, someone tells a joke or an interesting story and it's as if the magic box is awakened! In reality, most memories are stored relative to our senses and the role our senses play a role in creating the necessary links for recall. In the above example, our auditory and visual senses are the likely candidates. This is because words are stored as language and as pictures; hence why a picture is worth a thousand words!

However, most does not mean all because a special type of memory merely need fragments or anything remotely similar to something we've experienced or imagined. These special memories are emotional ones and are stored in the emotional centre's, with a myriad of connections throughout much of the brain. These emotional memories are triggered outside of conscious awareness, initiating feelings, e.g. anxiety or fear, which then initiates thoughts; this is also a two-way process. Consequently, relative to disorders like anxiety, stress or depression, this means that all too often the thoughts are potentially wrong. Nevertheless, we tend to believe our subjective interpretations and this can trigger the thoughts to increase in duration and intensity or, worse still, become obsessions. An example of this is the feeling we get, that the plane we will be flying on will crash. Or if we are in a lift it will get stuck or some other catastrophe will occur. Obviously, for these future based terrors, there's something in the present, held in memory, triggering the response but it's not real, it just feels like it is!

This is where hypnosis/hypnotherapy can help! While hypnosis has similarities with sleep, it is not the same state and I believe the difference may have something to do with the systems that involve circadian rhythms? These systems involve the suprachiasmatic nucleus of the hypothalamus, the habenula and the pineal gland. Of course, these nuclei have many connections with other brain systems and that probably accounts for much of the difference that clients experience during hypnosis.

Consequently, when it comes to the need for a life-changing intervention, it can be useful to consider, what are the circumstances that cause issues to arise? The environment we live in, coupled with our own particular perspective of life, and its meaning to us, in part, determines the way our brain is wired. Genetics, of course, play a part but life experience has a far more important role in deciding the way we encode and respond to our experience of life. Most of our memory is processed by the hippocampus but, relative to emotion, memories of protection/fear are also stored and processed by the amygdala and its close neighbours. In fact, the amygdaloid regions get to process vital sensory data ahead of the hippocampus and this can lead to an overreaction in certain situations. Essentially, it's a shoot first, ask questions later type of processing. We've all had one of those moments when we have overreacted, only to discover we were a little hasty later; c'est la vie!

The specific area of sleep, relating to this study and, in some sense, hypnosis, is NonREM stage 3 (slow-wave sleep, aka delta wave). However, in addition to the more popular brainwaves, Gamma, Beta, Alpha, Theta, Delta, there is another very important brainwave, PGO (Ponto Geniculo Occipital) waves. These waves originate in the pons (but include the thalami), part of the brainstem/hindbrain (the oldest part, evolutionarily speaking). They then traverse the lateral geniculate nucleus of the thalamus (the brain's sensory processor) lastly arriving in the primary visual cortex in the occipital lobe. These waves are involved in the processing of REM/NonREM states, mostly while we sleep but they do have some influence while we are awake. PGO waves are responsive to auditory stimulation (hypnotist's voice) and thus, theoretically, create feedback loops that allow hypnotic suggestions/therapeutic interventions to be inculcated into our subconscious. In a sense, new learning is introduced, consciously, then reintroduced, hypnotically, in a way that facilitates new memory consolidation or reconsolidates existing ones! When you think about it, isn't that all a life difficulty is, the replaying of neural processes (memories) that elicit a specific behaviour or feeling?

During the conscious (psychotherapeutic) part of the hypnotherapy session certain ideas, assumptions, suggestions etc. are posed to the client. Overtly most of the time but sometimes these are covertly introduced. Covert in the sense that the hypnotist knows the client does not know the answer. Why you may ask? It's because of the way our brain processes information that occurs outside of consciousness, i.e. transderivational search! The question is asked as if the client should know, and often clients answer as if they do but really it's not possible! For example, an old lady of 106 was asked the secret to her long life, she said she always drank warm water. What she couldn't know, is how long she'd have lived, if she drank the same way most other people do; a mixture of hot and cold drinks? The reason behind this covert type of fact-finding is to test the client's perspective, values or beliefs etc. For the hypnotic intervention to be successful, it is best to be mentally accepted in a way that's balanced and harmonious. Most of our difficulty, as humans, arises out of conflict or imbalance between the world within and the world that is outside of us. Essentially we have to walk the talk, there cannot be true balance and harmony if there is a conflict between these two worldviews. Of course, we cannot live without some imbalance, so, the balance of our imbalance is the key!

Much of this imbalance of conflict arises out of the way our brain processes our experience of life and the unique combination of our genetic pool. But that doesn't mean that the initial processing was correct. In fact, any experience can be subjected to reinterpretation or reframing, if it couldn't, how could we ever change anything? Hypnosis-therapy is the perfect tool for change, it allows us, through the uniqueness of neural oscillations (brainwaves) to rewire the way our brain responds to the same old data. A simple example of this is seen in fonts, some fonts are easy to read and some are extremely difficult. So, in a font that is easy to read, there is less chance of misinterpretation or misunderstanding. Some people speak this way, their tone or inflexion comes in the form of easy fonts, while others talk in a font that's akin to hieroglyphics. Worse still, some of us think in hieroglyphics; we don't even understand our own self-talk, consequently we talk in vague or ambiguous ways, leading to dysfunctional emotional outcomes!

Hopefully, at this point, you will realise for any of this blog to be of value in making changes in your life, the quality of your sleep is paramount! If it's not, then hypnotherapy can also help you with that aspect of life too. Therapy is akin to the manual for effective living and hypnotherapy is akin to the 'Quick Start Guide!'

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 what we would imagine! If you want to know more about how Hypnotherapy why not make an appointment for a Free Consultation?

For more information on the Free Consultation - Go Here Or, to book your Free Consultation today, you can do so here

The Research: 

During the hours of sleep, the memory performs a cleaning shift. A study led by a Spanish scientist at the University of Cambridge reveals that when we sleep, the neural connections that collect important information are strengthened and those created from irrelevant data are weakened until they get lost.

Throughout the day, people retain a lot of information. The brain creates or modifies the neural connections from these data, elaborating memories. But most of the information we receive is irrelevant and it does not make sense to keep it. In such a case, the brain would be overloaded.

So far there have been two hypotheses about how the sleeping brain modifies the neural connections created throughout the day: while one of them argues that all of them are reinforced during sleep hours, the other maintains that their number is reduced.

A group of scientists from the Ole Paulsen Laboratory, at the University of Cambridge (United Kingdom), has analyzed the mechanisms underlying the maintenance of memory during the phase of slow-wave sleep -- the third phase of sleep without rapid eye movements in the brain during which there is more relaxation and deeper rest.

"Depending on the experiences of a person and depending on their relevance, the size of their corresponding neuronal connections changes. Those that save important information are smaller and those that store the dispensable are larger," explains Ana González Rueda, the main author of the study and researcher at the MRC Laboratory of Molecular Biology (LMB) in Cambridge.

According to the expert, in the event that all these links were reinforced equally during sleep, the brain would be saturated by an extreme overexcitement of the nervous system.

In the study, published in the Neuron journal, the researchers stimulated the neuronal connections of mice subjected to a type of anaesthesia that achieves a brain state similar to the slow-wave sleep phase in humans.

In the words of González Rueda, the stimulation was carried out 'blindly' because the information contained in each of the links was not known. "We developed a system to follow the evolution of a specific neuronal synapse and thus study what type of activity influences that these are maintained, grow or decrease."

What is the maintenance of neural connections dependent on?

The results show that during slow-wave sleep, the largest connections are maintained while the smaller ones are lost. This brain mechanism improves the signal-to-noise ratio -- important information remains and the dispensable is discarded -- and allows the storage of various types of information from one day to the next without losing the previous data. That is, those that have already been considered relevant are kept in that state without having to reinforce them. According to González Rueda, the brain "puts order" during the hours of sleep, discarding the weakest connections to ensure stronger and consolidated memories.

"Although the brain has an extraordinary storage capacity, maintaining connections and neuronal activities requires a lot of energy. It is much more efficient to keep only what is necessary," says the expert. "Even without maintaining all the information we receive, the brain spends 20% of the calories we consume."

This research is a first indication of the electrophysiological mechanism of sleep and opens new horizons thanks to the development of a new way of studying live synaptic plasticity.

The next objective of the experts is to research the consequences of this type of brain activity for the maintenance of certain information and to analyze new phases of sleep. "In addition to the analysis of the slow-wave phase, it could be interesting to know what happens in the REM phase, during which dreams occur," concludes González Rueda.

Story Source:

Materials provided by FECYT - Spanish Foundation for Science and TechnologyNote: Content may be edited for style and length.

Journal Reference:

  1. Ana González-Rueda, Victor Pedrosa, Rachael C. Feord, Claudia Clopath, Ole Paulsen. Activity-Dependent Downscaling of Subthreshold Synaptic Inputs during Slow-Wave-Sleep-like Activity In VivoNeuron, 2018; DOI: 10.1016/j.neuron.2018.01.047