Mind reading no longer exclusively belongs to the domain of science fiction writers and mediums. Over the last 50 years, researchers around the world have been working on a system known as the brain-computer interface (BCI) which allows direct communication between the brain and an external device such a computer or a robotic limb. The main goal of this research is to develop technology capable of restoring sensory function to the blind or deaf, and restoring movement to patients suffering from paralysis. Major strides have been made in this endeavour over the last decade, and BCI technology is now even being adapted to commercial purposes such as gaming.
BCI technology is possible because of the way in which the brain transmits messages within itself and to other areas of the body. The brain is composed of around 100 billion cells called neurons. Messages are sent from neuron to neuron as an electrical impulse, created by ion imbalances in neuronal membranes. Neurons are insulated by a coating known as the myelin sheath, which prevents most, but not all, of these electrical impulses from escaping. The tiny portion of the electricity which escapes from the myelin sheath can be detected and this signal can be interpreted by computers. A second feature of the brain is also key to the success of BCI: neural plasticity – the ability of the brain to adapt to new situations. Patients suffering with brain damage illustrate neural plasticity; in many cases patients are able to, over time, adapt other areas of their brain to perform the tasks of damaged regions. Neural plasticity also enables the brain to adapt to interpret new input, such as that provided by the brain-computer interface.