Countless liaisons between the billion human neuronal cells in the brain make this intricate network an authentic beauty on its own. While you are reading this article, commands are being sent from different sections of the brain, speeding along its circuits in the blink of an eye to allow you to process and understand the words you are glancing at. What a precious and powerful engine is our brain!
This irreplaceable organ keeps fascinating us over and over again when it comes to its plasticity. Brand new connections can be formed by neurons if they are disrupted for some reason -- after a stroke or another cerebral accident, for example. The neighboring neurons get assigned to perform the tasks in order to maintain the brain’s functionality. It sounds like a miracle, yet not all body functions can always be restored completely. In sudden accidents, when the individual used to have a perfectly healthy brain prior to the misfortune, this process of ‘neuronal tasks replacement’ is much slower and often the sequel is a permanent injury. Let’s say the person’s lesion leaves him or her paralyzed. None of these patients wish to stay immobile at any extent for life, and at this stage is where our research is of great importance.
In my group, we are specialists in detecting a “movement intention” – that is, your brain’s intent to move a muscle. Our work deals with detecting specific synchronization and de-synchronizations of the neurons that are related to voluntary movements in the cerebral cortex using a technique called electroencephalography. In practice, it works this way: You imagine you move your right arm, for example, and our computer interface recognizes your intention, then transfers the information to a robotized arm that takes action and does the move. Fascinating, isn’t it? And no, it is not science fiction! It is reality, and this technology, called the brain-computer interface, can release someone from the handicap of a paralysis. Another example of the use of such interface is motion detection while a patient is under general anesthesia. Despite the fact that a person’s conscious state is monitored during a surgery, there is between 0.1% to 0.2% of chance she/he will suffer from an ‘Intraoperative awareness’. It means she/he becomes conscious during the procedure, but cannot signal it to the medical doctors. Severe post-surgery traumas can result from such happenings.
I really hope our findings will open up the possibilities of combating stroke-induced paralysis through robotic prosthesis and introducing new surgery monitoring systems, especially when general anesthesia is necessary. It is truly amazing to be capable to “decode” cerebral activity by placing electrodes on someone’s head. Don’t you agree?
I am Sébastien Rimbert, a PhD student working at the Loria/Inria lab at the University of Lorraine.