But the disease has many other less visible forms

With a prosthesis of 600 pixels can relearn how to read. 1,000 Pixels a visually impaired can recognize a face. "A vision of Paris Institute, Serge Picaud is working on one of the most difficult topics of the moment: the development of artificial retinas. These prostheses are designed to partially restore sight to blind the optic nerve is still operational. Currently, ophthalmologists must merely sensor consisting of a photosensitive matrix of 16 pixels. These rudimentary receptors give patients the ability to distinguish the shadows and to find relative autonomy in their daily lives.

This is not so much the manufacture of an artificial retina that problem. Ultra miniature photoelectric sensors are widely used in the industrial world. "The challenge lies in the level of the junction between the photoreceptors and the optic nerve that carries the information to the brain", indicates the Parisian researcher. It is in fact find a biocompatible material as liaison between the various components of the eye with a carpet of microelectrode (see illustration). Institute of vision, installed in the Hospital of the Quinze-Vingts in Paris, focuses on the diamond, which presents all of these benefits (this is pure carbon). If all goes well, experimental Prosthetics "high definition" might be available in five years. In the meantime, the Parisian Institute focuses on the implantation of prostheses of 16 pixels "to hand".

Serge Picaud is part of the handful of researchers whose projects were selected by the Foundation for medical research in its tendering on the brain machine interfaces. A discipline booming by two favourable Dynamics: the huge progress in the understanding of the cognitive functions and the arrival of miniaturised sensors. "These searches are a spectacular development in many countries and the France is overdue." "It is for this that we are mobilized," explains François Clarac neurobiologist, Coordinator of the program. The Foundation has invested EUR 1 million in 8 projects some of which are actual revolutionary.

The complexity and density of the neural network of the brain remain seemingly insurmountable obstacles. "A mm3 of brain contains about 10,000 nerve cells and each neuron is itself at the centre of a network of 10,000 connections." "As each neuron emits approximately 1,000 signals per second, it is facing a series of extraordinary complexity", said Yves Agid, Scientific Director of the future Institute for brain and spinal cord (ICM) under construction on the site of the Pitié-Salpêtrière hospital in Paris. This complexity can be bypassed by working in groups of hundreds of neurons. "The knowledge of the skeleton of the message can be sufficient," said Yves Agid. Researchers hope to reconstruct the full message by decrypting only a few words.

Kindling of the brain

This set of Neurobiological runway interested Olivier David physicist who said "very interested in the interface between physics and the life." From the Grenoble School of neuroscience researcher is passionate about a discipline which has the wind in its sails: intracerebral stimulation that has been proven in the illness Parkinson's. By electrically stimulating a specific area of the brain through 2 electrodes, it is possible to neurons in the right path. In the case of Parkinson's disease, the results are spectacular. A calibrated electrical signal precisely instantly stops the earthquakes of the body. It was tempting to use this method widely proven in the world for other psychiatric disorders. Olivier David retained epilepsy. Another scourge, of modern times which affects approximately 250,000 children in France.

Seizures are the result of an electrical disorder of the brain: excessive and sudden shocks produced by neurons in certain areas or even in the whole of the brain. This "kindling" translates paroxysmal attacks well known to the general public. But the disease has many other less visible forms. "The problem with the brain is that it is difficult to dissociate the healthy of the disease," said Olivier David. The work at the Institute of neurosciences of Grenoble are to develop a device capable to detect the imminence of a crisis and to send a signal intended to counter the phenomenon. "Within 5 years we will have demonstrated the concept of a neuromodulator for patients who do not meet available for epilepsy drugs", indicates the Grenoble researcher. This same technique could be used to treat other very disabling mental illnesses: some depression or obsessive compulsive disorders.

"How the brain controls hand, this essential instrument for the man." Marc Maier did not choose simplicity. It attempts to develop a humanoid finger controlled by cortical signals. It is one of the most difficult challenges of the technomédecine. The Americans have invested considerable amounts in this sector. Darpa, the Federal Agency, specializing in military research, pilot program of nearly $ 100 million for the development of "intelligent" artificial members In his laboratory of Duke University in North Carolina, Miguel Nicolelis has managed to make fly an arm robot by the thought of a monkey and similar experiments were conducted on humans. The Japan, a team of researchers at Honda obtained identical results with 2 fingers.

These experiments confirmed the extraordinary plasticity of the brain. After some time, the neurons are reorganizing to integrate and to appropriate the prosthesis as if it were a true member. "The repeated use of the device led to a functional reorganization of the brain and monkeys use the robotic arm as if it was theirs," recently indicated Miguel Nicolelis. A Parisian ICM, Yves Agid hopes to attract a few large sizes of the research to the global level in this very promising area of the neurorobotique. The Institute should have a budget of EUR 67 million and consolidate 600 researchers in 2010.