What would we be without our memories? Our brain's capacity of recalling the past is a mystery. Why and what do we remember? Where are the memories stored? Today, the scientists - by using modern technologies - are starting to find some answers.
Our memories are not cell groups nor information bits susceptible to be compressed, manipulated or traded. In fact, scientists are not even sure if memories store in a certain brain point. There are no memory centers. The memories are not unchangeable, but reconstructions in a continuous evolution.
What the neurologists studying the brain discovered is nothing similar to a computer. The millions of combinations inside the human brain are not countable and could not be reduced to a mathematical formula. The computer's capacities, even if superior to the human brain's in some fields, are nothing more than humble miracles compared to the marvels executed in each moment of our lives by our neurons. In their network, which turns increasingly dense during our existence, thousands of millions of chemical interchanges are continuously produced through compounds called neurotransmiters (acetylcholine, glutamate, serotonin, dopamine).
The connexions inside a human brain are estimated at about 500 billion. In this breeding ground the identity, habits, knowledge, emotions, memories, new ideas, associations are developed. Artists know it: memory and inventiveness are continuously and mutually fecundating each other. Memory is a dynamic conjunct, an opened and flexible system, in which the perceptions and the thoughts pass through many pathways. And these pathways, thoughts and perceptions vibrate, circulate, palpitate.
Some areas re-heat, other remain sleepy and can reconnect unexpectedly in a moment (the smell of a bun can recall the infancy). The researchers are attracted by these scars, details and crossroads, and make an effort to decode them with the help of the molecular biology or genetic engineering. But what they discover is not a content but an unlimited capacity of transformation and renovation.
Today, everybody acknowledges the strange power of our brain, which in case of accident or trauma, can open new pathways for the information circulation. The cerebral plasticity is what allows the persons that were born blind, when learning Braille, to use the brain areas normally where images are processed. In reality, if the memory cannot be localized in a specific area it's because it is found disseminated through all the cerebral matter. It appears that strokes do not erase memories; in reality, they act like a crack cutting off communication between two areas. Memories don't disappear; just the means to make them emerge are gone. Certain lesions can produce memory problems, but just one lesion cannot induce a total amnesia.
Memories are already not considered pre-established data, but operative processes, responsible for the organization of the perceptions. They are more than a huge collection of sensations, images, and words; it would be a mobile network, an evolutionary labyrinth; an aptitude of the brain's conjunct, a creative and individual capacity. The memories live and die with us, and are tightly connected to our personality, vision over the world, our habits, our love and our way of speaking, walking, sleeping and dreaming.
Without memories, we are not persons; the memory is our own being. However, the memory is extremely fragile. Since the emergence of the civilization, people have invented thousands of methods to conserve and develop the memory. The development of storing methods, like writing, printing, cinema and the computer, have produced an exponential increase of the storing capacity of the events. Faced with the competition of the artificial memories, what will happen with the art of memorizing, so priced in other times? Our electronic slaves have turned us lazy and made us decrease our memorizing ability. Learning by heart "by memorizing" has fallen obsolete in schools, the same way in which calculators made the classical and healthy mental calculation not fashionable anymore.
There is no better method of preserving our memory than forging projects for the future, which is a better remedy for the "old age forgetfulness" than having an active life, keeping on learning. The memory comes from the past but it lights up the future. This is the paradox by excellence; capricious, it always does what it wants. It is full of black holes, inaccessible regions. Our conscience uses only a minute part of our records: we remember just 1/100,000 of our childhood. Still, we can experience the emergence of the involuntary memories that make us instantly revive and relive disappeared worlds.
Even if it is a genial illusionist, the memory is hardly to be trusted. Sometimes, it can be influenced and induces us into making mistakes; sometimes, it gives us the tricky sensation of having already lived the present moment. Seldom, the judges encounter reliable witnesses. It is possible that memory is in reality nothing more than a classification center opened 24/7. While sleeping, our brain accomplishes mysterious repairing works, a type of gardening labor, which allows us to extend the framework of our most recent memories, restore the old networks, leave space for the arrival of new experiences.
During the day, the selection process continues in an implacable form. The so-called immediate memory lasts just a fraction of second, and immediately discards all superfluous memories. The long-term memory erases the memories that look useless, like the foreign language that is not practiced. The declarative memory blots out suddenly entire facets of our life. Anyway, there are no exact memories of the past, and this is explained by the fact that an exact memory would not allow us to survive in a world found in a continuous evolution.
Every minute, the conscience extracts from a sea of memories what it needs, without acting like an owner, without making an inventory. 84 % of the psychologists say that all that we have seen, known, perceived, heard exists in us, without us knowing it. It is impossible to prove the contrary. And the doubt never abandons us. How many times will I turn back on having this thought? How many times will I recall from my sleepy thoughts the memory of that poem, that childhood friend, that trip? How many of the sounds, scents and emotions from those secret archives will remain unused forever?