How Brains Predict Perception to Save Energy

This exciting article ‘To Be Energy-Efficient, Brains Predict Their Perceptions‘ discusses how “results from neural networks support the idea that brains are “prediction machines” — and that they work that way to conserve energy“. This has wide ranging consequences in perception and how we may be deceived by this predictive trait.

Many neuroscientists are pivoting to a view of the brain as a “prediction machine.” Through predictive processing, the brain uses its prior knowledge of the world to make inferences or generate hypotheses about the causes of incoming sensory information. Those hypotheses — and not the sensory inputs themselves — give rise to perceptions in our mind’s eye. The more ambiguous the input, the greater the reliance on prior knowledge.”

This results in the development of many models that approximate brain behavior when it comes to perception. Much work has been done on developing neural network models mimicking the brain, and analyzing their energy consumption. “The takeaway is that a neural network that minimizes energy usage will end up implementing some sort of predictive processing — making a case that biological brains are probably doing the same.”

This also explains many effects of visual illusions where the brain unconsciously infers an explanation to the image which may oversee another or be plainly wrong. This well-known phenomenon is also used in psychology to uncover our unconscious by studying what interpretations we spontaneously provide in those situations.

It is not surprising that evolution has found a way to minimise the brain energy consumption, which is already draining a lot of energy for itself. The balance between prediction and actual observation it has found may have made sense in the past, but does it make sense now? How can we exploit it or overcome it depending on the circumstances?

In any case the fact that neural-networks models have been developed of the brain that allow to explain some of its behaviors is a great step forward in understanding at least the perceptual part of the brain.


How to Visualize Trance Experiences through Narcosis Visions

Following up on the previous post ‘How Apnea Diving Leads to a Form of Trance‘ as well as our series on trance (see ‘What Does Trance Feel Like?‘ which contains reference to the series of posts on this subject), a leading French apneist provides an interesting visualization of the kind of visions he experiences in a short film ‘Narcose’ (narcosis).

Those visions give an idea of what some people may experience in certain trance states. Those visions are always very personal and not all trances lead to visions. However it is a short insight into this type of experience that is interestingly shared in this film. The director, the wife of the professional apneist, is also a practitioner of that sport, which may have helped produce a film closer to the experience.

Here is the Youtube link to watch the film:

Hat-tip to Laurent Coulon for the discussion on apnea diving and trance.


How Apnea Diving Leads to a Form of Trance

Following up on our series on trance (see the post ‘What Does Trance Feel Like?‘ which contains reference to the series of posts on this subject), one interesting practice that appears to be quite similar is what happens when one does apnea diving (also called freediving), because it requires brain adaptations.

Efficient apnea diving requires careful management of oxygen; the brain being the main oxygen consumer even basic apnea management requires to learn how to deplete the oxygen flow to the brain, and in particular the frontal cortex. This practice will significantly increase the time before breathing becomes absolutely necessary.

At the same time, this brain exercise necessarily leads to an alternate form of consciousness. Therefore, apneists are quickly in a form of trance state, focused on their performance of avoiding the urge to breathe again. Hypoxia then leads also to all sorts of visions and possibly dangerous behaviors.

Hat-tip to Laurent Coulon for the discussion on apnea diving and trance.


What Does Trance Feel Like?

To finish this series of posts about my exploration of trance, I am sure you all ask yourselves how it is like to be in trance. It’s difficult to describe, I’ll still give it a try.

Basically getting in a trance state is getting the habit of inhibiting our higher cognitive functions to allow subconscious processes to express themselves, through gestures and movement as well as noises. Visions appear including colors and sometimes impersonation of animals or things.

The amazing part is that one remains very much conscious during the experience, self-observing what happens and in a certain capability to recount the experience (although like a dream, memories tend to dissipate after a while).

It is not infrequent to produce sounds or perform movements that one would be quite unable to produce in a normal state (remember that trance increases strength and diminishes pain).

An important parameter is also that trance is quite a contagious state: during the training with 20-ish trainees and 5 or 6 experienced trance practitioners, the departure of a critical number of people in the trance state had almost an instant effect on the rest of the group.

Trance is quite an enjoyable state and in a way, is a method for self-healing emotional and physical conditions. In that matter, the power within can sometimes be extremely impressive.

As I am practicing and it will take weeks to increase my understanding of trance, I give you all an appointment in a few months’ time to learn more about trance, and possibly my adventures as part of the associated scientific experiments!

I hope you enjoyed this series of post on my personal journey into an altered state of consciousness – cognitive trance – that I was privileged to undertake this year. I will recount from time to time my experiences around trance. Stay tuned!

Previous posts in this series:


How Trance Has Become a Scientific Experiment

The most amazing part of my trance teacher Corine Sombun experience is that she managed to transform trance from a folkloric experience to a scientific experiment. And since 2018 she is training people to have a cohort of trance practitioners to check that measurements performed on herself are consistent for people trained to induce trance.

Pushed by curiosity Corine Sombrun, once she was a trained Mongolian shaman, tried to connect to scientific brain research institutes to better characterize this strange trance state she was practicing.

At the start no-one was interested and it was quite unclear for professors whether she was healthy or pathological: during trance she demonstrated clearly the combination of several pathological states, but at the same time she was able to come back to a perfectly healthy condition. This was surprising, so unconventional that it took a decade (!) for the first scientific paper on her capabilities to be published.

In the meantime she managed to get her brainwaves measured and studied. To achieve the best results one has to be perfectly immobile, which is not quite consistent with trance practice. However Corinne progressively managed to learn how to induce trance at will and be perfectly immobile during that state, so that electro-encephalograms could be measured (see picture), which showed a significant alteration of brain activity during the trance state. Those alterations were not very different from those measured in very experienced meditation practitioners; generally there is a change of the balance between brain hemispheres and a different activity in the cortex.

The current state of this evolution is the creation of a scientific institute on trance, the training of cohorts of trance practitioners, and an increasing number of projects about the capabilities of trance in a number of situations: for astronauts, people suffering from cancer, people close to die, artists that want their creativity to be boosted, people treated by psychologists or psychiatrists etc…; and also what trance brings to common people in their daily life.

And that’s how I was privileged to join this cohort training to be part of the experiment.

In a series of post I will describe a personal journey into an altered state of consciousness – cognitive trance – that I was privileged to undertake this year. Previous posts in this series:


How Shamanistic Trance Inducers Are Quite Ineffective

Traditional shamanistic ceremonies are based on the shaman inducing a trance state on himself or herself to look at situations presented to him or her beyond normal consciousness.

Most “primitive” societies rely on some kind of shamanistic ceremonies to resolve issues and problems. Depending on cultures and locally available drugs, the shamanistic trance can sometimes be induced by drugs, but is most often the result of a capability that has been trained by another shaman.

Shamans in those cultures are usually quite rare; in Mongolia (before shamanic ceremonies became touristic), Corine Sombrun estimates there were about a ratio of 1 per 100,000 inhabitants.

Trance induction using for example a drum or some other instrument that creates a trance-inducing sound appear to be somewhat ineffective and are only active on the shaman and a limited number of particularly sensitive individuals. Experiments carried out by Corinne on the basis of shaman drum ceremony recordings have failed to induce trance in the listeners.

The challenge that Corine Sombrun grappled with was how to find a more effective way to induce trance, and she has progressively, through trial and error, found specific rhythms and sounds that tend to create trance in a majority of people. Those are the sound loops I have been subjected to during my training.

In a series of post I will describe a personal journey into an altered state of consciousness – cognitive trance – that I was privileged to undertake this year. Previous posts in this series:


How My Teacher Corine Sombrun Discovered Trance Practice

Corine Sombrun (link in French), my trance teacher, has quite an incredible destiny. The amazing part is how she managed to transfer a millenia-old shamanic practice into a scientific experiment of an alternate state of consciousness.

She is a musician and composer, as well as sound engineer. During a BBC-commissioned trip to Mongolia at the start of the 2000s, which followed a difficult personal emotional period of mourning her partner, she entered a trance state unexpectedly during a shamanic ceremony. The shaman struggled a bit to bring her back and then announced to her she was a great innate shaman and she had to learn to become a full shaman.

Under the shamanic threat of not being able to regain her inner balance, she travelled several years in succession to Mongolia for her shaman-training, ultimately becoming a shaman herself (and participating to shaman competitions!). The picture shows her with her shaman-teacher.

The tale of this learning experience was so dramatic that her book rights has been acquired by the movie industry and a movie was produced in 2019 with a well-known French actress (who also was trained in trance!): “un monde plus grand” (a wider world)”.

Beyond the traditions of shamanic trance, she was able to train and develop her trance state, increasingly being able to induce it easily. However she was still very much requiring all the shamanic associated contraptions like the drum and other folkloric impedimenta. Soon however, pushed by curiosity, she was able to work on better characterizing this state, and induce the trance-state differently – to be followed in a subsequent post.

In a series of post I will describe a personal journey into an altered state of consciousness – cognitive trance – that I was privileged to undertake this year. Previous posts in this series:


How I Was Taught to Self-Induce Trance At Will After Only a Few Hours

Going through a special training I have discovered how to self-induce trance states at will. It then takes some practice to anchor the possibility, but the capability is amazingly acquired quickly. I really did not believe at first I would be capable of obtaining this state (being a highly cognitive and controlling individual), and even less so that I would be able to induce it at will after only a few hours.

In previous posts I have described the state of trance and how it happens around us more frequently than we think. Still, it is usually quite a rare occurrence often associated with situations of emergency or only attainted by practitioners of certain disciplines after considerable amount of practice (e.g. through meditation).

The training was given out by Corine Sombrun, a quite exceptional woman with an incredible destiny (more about her in future posts). She has designed this protocol for teaching how to obtain trance states at will and is currently building up a cohort of psychologists and researchers to participate in scientific experiments around that altered state of consciousness. Because of the way trance is induced, it is called ‘cognitive trance’. The amazing part is that her success factor in getting people to induce trance and then to learn to induce it at will after only 2 days of training is close to 100%!

This shows that trance is not a weird state reserved for exceptions, but that it is an underlying consciousness state that we can all attain if we follow the proper protocol (and without any legal or illegal substance involved). While the benefits of the practice are currently under investigation, the simple fact that it is attainable by all makes it an incredibly interesting field of investigation.

In a series of post I will describe a personal journey into an altered state of consciousness – cognitive trance – that I was privileged to undertake this year. Previous posts in this series:


How ‘Flow’ May Assimilated to a Trance State

Flow, as defined by Mihaly Csikszentmihalyi, involves Optimal Experience, when “a person’s body or mind is stretched to its limits in a voluntary effort to accomplish something difficult and worthwhile“.

In fact, now that I have investigated trance-state, and haveing had experience of Flow, I can affirm that flow is some kind of soft trance state. Flow is “a state of concentration or complete absorption with the activity at hand and the situation. It is a state in which people are so involved in an activity that nothing else seems to matter“. It is a state where the sensation of time gets lost.

Those symptoms are typical of a trance state (as well as the intrinsic pleasure associated with it, and the fact that one seems to be on a different level of consciousness): “This is a feeling everyone has at times, characterized by a feeling of great absorption, engagement, fulfillment, and skill—and during which temporal concerns (time, food, ego-self, etc.) are typically ignored

Flow is thus another example of commonly accepted alternate state which is in fact an example of trance-like state, which many of the associated symptoms. Flow is also a state that can become a habit and for which we can consciously traing.

We really underestimate how much and often we can find ourselves in alternate consciousness levels in our activities, in particular those we are really passionate about.

In a series of post I will describe a personal journey into an altered state of consciousness – cognitive trance – that I was privileged to undertake this year. Previous posts in this series:


How Trance Is Common Around Us But We Don’t Realize It

Since I was introduced to trance and had more thoughts about this particular awareness state I have realized that I have witnessed actual examples of trance in my life.

The more emotional example is when I witnessed the celebration of Thaipusam. It is the occasion for many devotees to thank the deity for some gift. At that occasion, people parade with needles, hooks embedded in their skins and other bloody and painful contraptions. In fact they are set in trance by priests at the start of the parade. Trance allows them to easily bear pain. What impressed me the most when I followed such parade from the inside in Kuala Lumpur, a famous location for this festival, is how people were being set out of trance in an instantaneous manner by priests at the end of the parade. They also expressed quite a different behavior and character during the parade itself (and were carefully shepherded by helpers during their trance).

Another example is when I was confronted to someone being ‘possessed’ – also during a spell in south-east Asia. The poor lady was effectively suddenly shivering and seemed to be in another state of consciousness, with inarticulate sounds and random movements. In a religious context, exorcists were brought in and after some time the lady regained normal consciousness (whereby the exorcists concluded they were effective at drawing out the evil spirit that inhabited her).

In western civilisation such occurrences are less often related however there is no doubt that spontaneous trance states do occur. Trance is thus a state which many people encounter in their life, sometimes without identifying is as such.

In a series of post I will describe a personal journey into an altered state of consciousness – cognitive trance – that I was privileged to undertake this year. Previous posts in this series:


How Trance Is a Common Altered State of Consciousness

Trance is a very ancient altered state of consciousness, that is known and recognized explicitly by more than 95% of the “primitive” tribes. It is often related to ecstasy experiences such as religious ecstasy, and there are many references to this state in literature and even common expressions.

According to Wikipedia “Trance is a state of semi-consciousness in which a person is not self-aware and is either altogether unresponsive to external stimuli (but nevertheless capable of pursuing and realizing an aim) or is selectively responsive in following the directions of the person (if any) who has induced the trance. Trance states may occur involuntarily and unbidden.

The interesting part of the definition is that it is an altered state of consciousness where it is nevertheless possible to pursuing and realizing an aim. It is at the same time detached, and still enabling consistent action.

Wikipedia also offers the following definition which I find very adequate from my experience: “trance may be understood as a way for the mind to change the way it filters information in order to provide more efficient use of the mind’s resources

And it is exactly this type of state that I have been introduced to, and that I am practicing daily for the last few weeks – because it appears that it is possible to induce trance only though the application of one’s will.

In a series of post I will describe a personal journey into an altered state of consciousness – cognitive trance – that I was privileged to undertake this year. Previous posts in this series:


A Journey Into Altered States of Consciousness: Introduction

In a series of post I will describe a personal journey into an altered state of consciousness – cognitive trance – that I was privileged to undertake this year. It has led to a lot of self-reflection and discoveries. First I believe it is important to set the scene.

Altered states of consciousness are according to Wikipedia “any condition which is significantly different from a normal waking state“. They can happen naturally for example during emergency situations where the brain shuts down higher cognitive functions for survival – for exemple during near death experiences, or during emergencies where some people can react with unexpected strength and endurance. It can also be generated voluntarily, sometimes using legal or illegal substances.

Some of those altered states of consciousness can be pathological (leading to significant social and personal dysfunctions); most occurrences however are transient states encountered (or actively sought after) by normal individuals. Hypnosis, meditation, mantra recitation are often cited as examples of methods to reach those states of consciousness where basically the higher functions of the brain are temporarily limited, allowing a stronger expression of the subconscious. Trance is a particular healthy state of altered consciousness that I have been exploring for a few weeks, and the following posts will recount this journey.