Sleep and dream are still the two major mysteries of the brain. Since time immemorial mankind has been intrigued as to why we sleep and what is the nature of dreams. In my personal case one of my earliest memories was of powerful, vivid dreams. At the young age of 4-5 years with hardly any experience to influence these episodes it was amazing to get such dreams. Later on, there were even better episodes of great dreams. Hence a tremendous curiosity arose in my mind about the nature of dreams and sleep and thus this small study. 

Various theories exist about the sleep process. We spend almost one third of our life sleeping. There must be a good reason why nature makes us sleep for this much time. Now slowly but surely scientific investigations are unraveling this puzzle. 

Why do we sleep?

One of the accepted theories so far has been that sleep helps in consolidating and also removing the memories. We perceive the world during the day through our senses and this results in memory formation, either shallow or deep. Sleep, it seems, helps in consolidating or removing some of these memories and unclutter the brain.

Another theory suggests sleep helps in flushing out toxic protein waste and other biological debris from the brain. These toxins are produced in the regular functioning of the brain during the waking hours. Research has also shown that in sleep the connections between neurons are slightly loosened and this helps in opening up the channels through which the debris flows into the blood stream and is removed from the brain. 

With sleep deprivation the toxin load builds up and leads to judgment impairment, mental illnesses like depression, heart problems, obesity, and drastic reduction in general well-being of an individual. In fact, the first sign of sickness is a fretful sleep. In an extreme case, long term sleep deprivation has also resulted in death; though the cause of death was reported as heart failure which could have been triggered by sleep deprivation.

Large numbers of studies have also shown the beneficial effects of good sleep.  Some of them have also shown that during good sleep amyloid plaques and tau tangles which are thought to be responsible for neurodegenerative diseases like Alzheimer’s and dementia are flushed out. Thus, good sleep is extremely essential for a healthy brain and body.

During sleep we go through four or five cycles of deep sleep and dreaming episodes. Each of these cycles is of 90 minutes duration. Why these cycles exist nobody knows. Electroencephalography (EEG) studies done on human brain (during sleep) show that deep sleep is characterized by the production of low frequency (1-4 Hz) Delta waves which are known to help produce life and mood-enhancing chemicals. During this stage we are totally unaware of the surroundings. Thus, when we wake up after a good deep sleep it is very refreshing and invigorating.

On the other hand, dreaming episodes, which are characterized by rapid eye movement (REM), produce light sleep from which one can be woken up quite easily. The brain waves during REM sleep are similar to those during wakefulness and sometimes produce lucid dreams.  REM also exists in nearly all animals.  

So, what is the nature of dreams; how are they formed and why only some of us remember them?  Nature of human thought and memory formation may throw some light on it.  

Dreaming process

Human thought is a hologram which is formed when neurons fire. During this process neurons communicate with each other and form neural pathways. For each thought unique neural pathways exist and the memory of that thought are the arrangement of neural pathways and the sequence of the firing of neurons.

One of the attributes of sleep is losing control of consciousness, muscle strength and hence the sense of ego or 'I'. The ego during the waking state provides the energy to focus on a particular thought or idea but during sleep, with ego or ‘I’ being nearly absent, the randomness of thoughts results in disjointed and weird dreams.      

Brain never sleeps is an old adage. It is an autonomous system and produces constant energy and inputs for the neural pathways to be excited and formed. Since the neural pathway connections during sleep are loosened this allows them to be continuously formed and broken producing random disjointed thoughts which are the signature of the dreaming process.

It can also be conjectured that the newly formed memories (outcome of recent daily activities) are more prone to getting their connections loosened. Also, with distance between neurons increased (because of loosening) there is a greater resistance to neural communication.

Since the loosened neural pathways provide resistance to excitations, those neural pathways which have strong connections (providing the path of least resistance) may get energized readily. These are the deep-seated and strong memories which are suppressed and dormant during normal waking hours but get activated during sleep. 

This is how the subconscious brain which has the neural pathways (memories) of deep-seated desires and fears gets stimulated during sleep resulting in wishful and nightmare dreams. Active resolution of these memory knots during the waking hours is the best way to ensure that we have fewer dreams about them. In a way dreams are a mirror to our insecurities and subconsciously tell us or goad us to resolve them.

Similarly, during lucid dreams, the neural pathways somehow have a better and non-lossy connection and hence remembrance of dreams is better. We still do not understand how and why this happens. 

Prophetic dreams

Throughout the history of mankind and in every religion and society dreams and sleep have been thought to be a mechanism to connect the physical world to that of the supernatural. Thus, before Buddha’s birth his mother Queen Maya dreamt that a white elephant had entered her body. Similarly, the mother of Sri Sri Ramakrishna dreamt that a small green figure, whom she identified as God, was telling her that he will be born in her house and Mother Mary dreaming about the birth of Christ. In one of the most celebrated case President Abraham Lincoln saw his own death in a dream .

At the same time there are innumerable instances of solution dreams in the annals of human history. For example, Kekule’s benzene structure, Mendeleev’s invention of periodic table, Howe’s invention of sewing machine, and Neils Bohr’s atomic model came in their dreams. There are also a large number of examples where scientists, inventors and technologists have literally dreamt up solutions to problems which they could not get in the waking state.

How does the mind produce prophetic and solution dreams? As we have seen, most of the dreams are disjointed and random. However, under certain circumstances, about which very little is known, the brain synchronizes the random thoughts into a powerful single thought. This is almost like a samadhi where the majority of neurons of the brain synchronize in a laser like fashion to produce a higher dimensional thought signature. This thought connects us to the knowledge space from which we get the knowledge and powers of clairvoyance.

The probability of this type of synchronization is very small but still is finite since the dreaming brain follows the Normal distribution or the Bell curve where prophetic and nightmare dreams lie at ends (outliers). Quite a number of people sometime or the other in their lifetime are blessed and do get such prophetic dreams, which help us understand the existence of higher thought and reality. However, such prophetic and solution dreams come to those who have a prepared mind and have been thinking deeply about these problems.

Dreams reflect what we eat

There is a strong interaction between gut and brain.  Hence the gut health affects the brain directly.  The connection between the two is via the Vagus nerve and the blood stream.

Consequently, it is quite possible that the dreams are affected by what we eat.  Recently scientists have found this to be true in a study done on more than 1000 volunteers where they studied the dreams and correlated with what they ate. Mahatma Gandhi intuitively understood this interaction of gut and sleep.  He used to take enema before sleeping and this resulted in deep dreamless sleep.

Can dreams be produced at will?

Since the ever-present director-the ego sense ‘I’ is reduced during the dreaming process, we have no control over our dreams. However, we can control our day’s events which are normally reflected in our dreams. Yogis have all along claimed that Sanyam helps in producing a powerful thought process which ultimately leads to a non-REM or dreamless sleep. Recent evidence from sleep research corroborates it. 

Scientists have discovered that REM and non-REM sleep are totally dependent on how active the brain is during daytime. The high-density EEG scans of sleeping volunteers’ brains show that most of the dreaming activity takes place in the region of the brain which was most active during the day time. Scientists have also discovered that non-REM or slow-wave dreamless sleep occupies the central position in the sleep process. The information and memory consolidation process takes place in the brain only during non-REM sleep. Hence REM sleep is simply a mechanism for the brain to check whether the memory consolidation has taken place. 

Thus, to produce happy and productive dreams one needs to be active mentally and physically during waking hours. Whatever memories we make during daytime are reflected in our dreams, including prophetic dreams. Probably the solution dreams of great inventors also came because of the very active prepared mind during waking hours.

There is still no single definite theory of sleep and dreams. However, the jigsaw puzzle is slowly being assembled by research inputs from all over the world. As our science and technology advances, we will probe deeper into the mysteries of sleep and dream because they provide the best windows for getting a peep into the workings of the human mind and ultimately will lead to the knowledge of the nature of consciousness and of human thought.                       

(The writer, an IIT and US-educated Indian spiritual engineer and rural development pioneer,  a 2022 Padma Shri award winner, is the Director, Nimbkar Agricultural Research Institute, Phaltan, Maharashtra.  He can be reached at anilrajvanshi50@gmail.com/@anilraj24.bsky.social)