In early 2000, scientists implanted electrodes into the eye of a blind man. They then connected electrodes to a camera on a pair of glasses for the man to wear. As a result, he began to see images of light. A second generation of these implants constituted the first commercial use of BCIs. In the newer versions, more electrodes connected to the retina and therefore formerly blind individuals could see enough to drive slowly around a contained parking lot. The implant functioned more effectively when the individuals receiving them previously had the ability to see. While the individuals still cannot see perfectly with the implant, the change from blindness to a partial ability to see represents a huge advancement in the realm of Brain-computer interfaces.
Since then three types of BCIs have emerged: invasive, partially-invasive and non-invasive. Doctors implant invasive BCIs directly into the damaged part of the brain. Typically they help to repair damaged sight and functionality of limbs in people with paralysis. Partially-invasive BCIs are implanted underneath the skull in the grey matter surrounding the brain. They are more effective than non-invasive BCIs because the skull cannot mute electrical signals passing from the brain to a computer. Finally, non-invasive BCIs record brain electrical signals from outside the body. These include such processes as magnetic resonance imaging (MRI), electroencephalography (EEG). While they are beneficial in diagnostics, these non-invasive forms of BCIs cannot clearly pinpoint the locations of the brain from which signals are derived[2].
While brain-computer interfaces and neurotechnology have allowed for significant scientific and medical advancement, many applications are still in the beginning stages. For instance, the United States armed forces fund a program known as Silent Talk (specifically funded by DARPA, Defense Advanced Research Projects). Recordings of neural signals of speech production would allow soldiers to communicate on the battlefield without vocalizing their words. The technology would utilize EEG non-invasive BCIs to transmit the signals[3]. Neurotechnology will advance exponentially in years to come for use in medicine, toys, and research.
[1] Lebedev, Mikhail A., Miguel A.L. Nicolelis. “Brain-machine interfaces: past, present and future.” Trends in Neurosciences 29. 21 July 2006.
[2] Sitaram, Ranganatha, Andrea Caria, Ralf Veit, Tilman Gaber, Giuseppina Rota, Andrea Kuebler, Niels Birbaumer. “fMRI Brain-Computer Interface: A Tool for Neuroscientific Research and Treatment”. Eberhard-Karls-University of Tubingen. 28 February 2007.
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