The history of brain–computer interfaces (BCIs) starts with Hans Berger’s discovery of the electrical activity of the human brain and the development of electroencephalography (EEG). In 1924 Berger was the first to record human brain activity by means of EEG. Berger was able to identify oscillatory activity, such as Berger’s wave or the alpha wave (8–13 Hz), by analyzing EEG traces. Brain–computer interfaces are systems that use signals recorded from the brain to enable communication and control applications for individuals who have impaired function.
Berger’s first recording device was very rudimentary. He inserted silver wires under the scalps of his patients. These were later replaced by silver foils attached to the patient’s head by rubber bandages. Berger connected these sensors to a Lippmann capillary electrometer, with disappointing results. However, more sophisticated measuring devices, such as the Siemens double-coil recording galvanometer, which displayed electric voltages as small as one ten thousandth of a volt, led to success.
Berger analyzed the interrelation of alternations in his EEG wave diagrams with brain diseases. EEGs permitted completely new possibilities for the research of human brain activities. Once just a science-fiction notion, the idea of controlling machines with thought alone is now a reality. With the proof-of-concept phase in the past, researchers think that brain–computer interface technology should now move from the laboratory into people’s lives.
The technology works by recording electrical brain signals—local field potentials or neuronal action potentials (spikes)—from the scalp, the cortical surface, or within certain movement-controlling areas of the brain (eg,
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In the DARPA-funded study, researchers at the University of Melbourne have developed a device that could help people use their brains to control machines. These machines might include technology that helps patients control physical disabilities or neurological disorders. The results were published in the journal Nature Biotechnology. In the study, the team inserted a paperclip-sized object into the motor cortices of sheep. (That’s the part of the brain that oversees voluntary movement.) The device is a twist on traditional stents, those teeny tiny tubes that surgeons stick in vessels to improve blood flow.
The new development makes it easier to stick a computer chip or stentrode into a patient’s head. Instead of open-brain surgery, the method of inserting a BMI through blood vessels in the neck reduces the risk of inflaming tissue and other risks involved in such horrifying, invasive surgery. It is just a matter of time before I can write this article just by thinking about it.
