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Improving processing capabilities through focused stimulation
Our brain, as any brain, is a processing and storage device with no clear separation between the two functions. In this sense it is quite different from a computer. Unlike a computer it does not have a “bus” rather a mesh of connections that are also processing signals as they are carrying them and “remember” the communications that took place to the point of influencing future communications, another difference with computers where the communication bus is just a … communication bus. Synapes have been found to be processing points, there are a 100 trillion of them and they are on the communications links (dendrites).
Furthermore, the whole brain operation is conditioned by chemicals, like dopamine, serotonin and many more, percolating in the brain that are also the result of its activity.
All this complexity tells us that it is quite difficult to find ways for improving a specific brain functionality through a focussed stimulation.
It has been possible to interfere with brain processing by implanting electrodes (Deep Brain Stimulation – DBS) as an example in blocking epileptic attacks, and to decrease symptoms in Parkinson disease. DBS is also being experimented for relieving depression although there is not yet a consensus on the effectiveness of DBS in this area with more recent studies casting doubts on the effectiveness of DBS on depression.
A newer approach is TES, Transcranial Electrical Stimulation, where the idea is to interfere with the brain’s electrical activity by placing electrodes on the head. This is clearly providing a even less focussed interference than DBS, however progress in the possibility to finely tune the electrical fields generated by several electrodes on the skull is making possible to generate focussed electromagnetic beams in specific brain areas. Being a non invasive procedure it makes it more acceptable and it makes it easier to experiment with it.
A third approach, much more focussed, is using optogenetics. Here specific neurones can be modified to become sensitive to light and by implanting an optical fibre it becomes possible to activate, de-activate a single neurone. The problem here is that there is not such a thing as a single neurone responsible for a specific activity (which is good since it makes the brain much more resilient!) and it is therefore close to impossible to interfere with the brain processing by interfering with a single neurone. Optogenetics has proved very effective in learning more on the fine processing going on in the brain and it represents a possibility to tackle some brain issues, like blocking pain signals.
A fourth way is to use chemical substances that interfere with the brain. Caffeine is a well known example -widely used!- that has stimulating capability on the brain, facilitating, to a point, focussed thinking. A growing set of substances are becoming available to stimulate the brain, so called nootropic drugs.
They have a broad effect, since these substances pervade the whole brain (and body) and are more likely to influence the overall processing (and storage effectiveness) of the brain, as it happens with the natural substances produced by the brain (and body glands with neurotropic effect). There is the possibility of finding substances that can have more specific effect on certain brain functions but this remains to be seen.
A fifth approach that might become available in the future is using nootropic drugs in a focused way, delivering them to a specific area of the brain using an implanted chip as a dispenser. Clearly this would require an invasive procedure but it would reach the goal of limiting the effect of a nootropic substance to a limited area of the brain.
Potentially, a mixture of all these approaches might be used and may lead to a fine control of the brain working. We are not ready for that today, as much more understanding on how the brain works is needed.
