A composer performed music with his brainwaves in 1965, before brain-computer interfaces had a name
In Alvin Lucier's Music for Solo Performer, the performer produces alpha waves, and amplified EEG signals set percussion instruments rattling through loudspeakers. That was 1965. Jacques Vidal coined the term brain–computer interface in 1973, and decades of research later, devices now translate brain activity into cursor movements and robotic arm commands.
A brain–computer interface measures brain activity and turns it into a useful output, bypassing the hands and feet altogether. Designs are graded by how close the electrodes sit to brain tissue, from caps and scanners outside the skull, through sensors on the brain's surface or inside blood vessels, to microelectrode arrays pushed into the cortex. Because the brain is plastic, it can learn to treat signals from an implant much like its own senses or muscles.
The groundwork goes back to 1924, when Hans Berger became the first to record human brain activity by EEG, first with silver wires under patients' scalps and later with a Siemens galvanometer sensitive enough to register tiny voltages. He identified rhythms such as the alpha wave. Vidal, working at UCLA with National Science Foundation and later DARPA funding, published the first peer-reviewed work in the field and in 1977 had volunteers steer an object through an on-screen maze using EEG signals. By 1988 a robot could be started and stopped along a line on the floor by EEG alone.
Animal studies did much of the heavy lifting. In 1969 monkeys at the University of Washington learned to move a biofeedback needle with their neural activity. In the 1980s Apostolos Georgopoulos at Johns Hopkins found a mathematical link between individual motor neurons and the direction a monkey moved its arm. Miguel Nicolelis at Duke favoured spreading many electrodes over wide areas, and by 2000 his team had a real-time system copying owl monkey movements in a remote robot. Other laboratories got working results from just 15 to 30 neurons.
BCIs overlap heavily with neuroprosthetics, which replace lost nerve function. Cochlear implants, the first such device, had reached some 736,900 people by December 2010. The first neuroprosthetic implants in humans came in the mid-1990s. More recently, DARPA has funded groups including Synchron and Paradromics since 2013, and in 2021 Elon Musk announced that a Neuralink-equipped monkey could play video games.
Source: Brain–computer interface
