There is not, up to the moment, any satisfactory explanation for the mechanism of formation of a conscious experience. The computer model, perhaps valid to explain the memory process, does not fit consciousness, since the machine, besides the fact that it can not "create" or "feel", does not possess the necessary requirements to explain the unitarian characteristic of consciousness, expressed by the fusion, during a certain period of time, of all our perceptions, thoughts and emotions; Without this unity, the person does not have, as he goes through day-by-day experiences, the feeling of individuality, of a single and indivisible being. And that is, precisely, what consciousness means: individuality, subjectivity. The self.

The theory of neural assemblies represents, in our opinion, the most coherent idea to allow the formulation of a hypothesis about the formation of consciousness. It follows, as a sound question, to ask whether there is any model or physical system that can explain the formation of the neural assemblies. In spite of the complexity of the subject, two physical systems were identified as being possibly involved in the process.

They seem to compose a chain of events, that are plausible enough to be accepted by our logical reasoning. Both are based on principles of quantum mechanics and capable to function in biological tissues. They are the Bose/Einstein condensate and the Frohlich effect. As it was already pointed out, the assemblies are transitory functional units, formed by neurons "borrowed" from permanent anatomic units (the neural columns).

However, how can one explain this functional "recruitment" of neurons ? A satisfactory explanation would be to consider that the process starts by the occurrence of a Frohlich effect. But, is there such a system in the brain ? It looks like that the answer is yes and that it is expressed as follows: The permanent electric discharges that occur in the spaces between the neurons, whenever the brain is activated by an stimulus, constitute the source of energy that impels the molecules of the cells membranes to emit photons. And, when this emission reaches a critical frequency, the molecules inside the membranes of millions of neurons, start to vibrate "in unison" , getting into a phase of Bose/Einstein condensation.

Thus, a single identity is created, an indispensable requirement for the formation of consciousness. Then, the neurons from multiple columns discharge, simultaneously. An assembly is formed and consciousness "explodes". As a conclusion to the hypothesis, we may consider that consciousness is an emergent property originated from the ""firing", "in unison", of an undetermined number of neurons, which spreads, diffusely, through out the brain, for a variable period of time, and when this time is over, it is, immediately, substituted by another one, and then by another one, and so on, and so on... However, in spite of all this sequence of events, so well structured that it is acceptable by logic, a mystery remains, and we do not know for how long it will persist. Actually, is it not the brain, as Restak proclaims, the last frontier of human knowledge ? But, what is this mystery, this bridge between the undetectable consciousness and the detectable neuronal assemblies ? It consists in the unknown but precise mechanism by which, within an infinitely short period of time, the vibration of a super condensed matter, produced by neuron molecules, liberates the energy that will be expressed as an abstract conscious thought.

What takes place, in this extremely small fraction of a second, is as indeterminable as what happened, in that very initial instant of the Big-Bang, when another matter, billions of times more condensed, gave rise to the universe.

And now ? What comes next ? Certainly, we have a long way ahead to reach a more precise knowledge on this subject. Particularly, we must try to understand that mystery : how is it possible that intangible things, like thought and consciousness are built from detectable and measurable elements, such as condensed phases, electric activity and neurotransmitters ? Perhaps the gap between the concrete and the abstract will be closed, some day. Maybe, when the interrelation between certain quantum and biological phenomena will be totally understood.

The way towards that goal has been searched by many investigators. It is a long and difficult journey. But it seems that they are doing well. Recently, a group of physicists, from the Weizman Institute, in Israel, directed by Amiram Grinvald, working with dyes, very sensitive to electric voltage - which allows the visualization of neurons "burning up", in large scale - found out that even a simple visual stimulus gives rise to a more complex brain response, one that grows, gradually in time, as more and more neurons are "recruited". Just like Greenfield had anticipated when she proposed her theory of neuronal assemblies.

Grinvald goes farther : "Equipped with a tool with which to visualize neuronal assemblies, we have also examined the organization of on-going (spontaneous) activity. We found that even in primary sensory areas, the spontaneous activity of single neurons is time locked to the coherent activity of numerous neurons over a large cortical area." Ad Aertsen, also from the Weizman Institute, states : "neurons can rapidly associate into functional groups to perform a computational task. Once the task is completed - this may take only a fraction of a second - the group is resolved, and the neurons are ready to engage in new, possibly different groups, depending on the task." Another team, from the Hebrew University, in Tel-Aviv, by registering different cortical areas of a monkey`s brain, verified the same thing : groups of neurons can get organized to perform specific tasks and, later, reorganize, forming new groups, in order to execute new functions.

These experiments must be regarded as serious ones, considering the people involved. It is a well known fact that Israeli scientists love to theorize. But it is also universally recognized that they are very careful and rigorous with their experiments. Actually, to theorize means to create hypothesis, whose validity has to be tested by scientific methods. Obviously, more experiments are necessary to dissipate some doubts that still persist about Susan Greenfield`s theory. Anyway, the Israeli findings mean a significant advance, since they demonstrate that some theoretical propositions, related to abstract phenomena, like consciousness and perception, can be confirmed by precise and scientifically trustful experimental methods.

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