26 October 1998: First computer controlled using thought
The human
In 1997, a blood vessel burst in the brainstem of Vietnam War veteran Johnny Ray. The stroke left him almost completely paralysed – he could move his tongue, the muscles of his face, his eyeballs – and couldn’t breathe on his own. But Johnny Ray (JR) was fully conscious; he could see, hear, and think. The name for this condition is locked-in syndrome.
The following year, JR agreed to have a neurotrophic electrode implanted in his brain. The device was invented by neurologist Philip Kennedy, and implanted by his colleague and fellow neurosurgeon Roy Bakay. Thanks to the brain implant, JR was able to express himself by indicating phrases on the computer screen such as “I am thirsty” and “It was nice talking to you”. Over time, he learned to move the cursor to specific letters of the alphabet, spelling out his own name, as well as those of his doctors.
JR was the second person to receive the implant, but only the first to successfully communicate with a computer using his thoughts. He died in 2002 of a brain aneurysm.
The device
In designing the electrode, Dr Kennedy knew the device had to be wireless, biologically compatible, and capable of chronic implantation – only then would he be able to observe the neurons firing as the subject learned tasks.
The neurotrophic electrode consists of two tiny (the whole thing is about the size of the tip of a ball point pen) hollow glass cones, which are coated with neurotropic chemicals extracted from the recipients’ own peripheral nerves. Dr Bakay explained at the time, “This puts the cells inside the cone so it keeps the cells going for a very long time. It is critical to train these cells in a stable environment. The nerve tissue grows into the cone and forms contacts or synapses.”
These contacts allow neural signals to be picked up by recording wires placed inside the glass cone which are then transmitted through the skin to a receiver and amplifier outside of the scalp. (There are no wires going through the skin - the system is powered by an induction coil placed over the scalp.) The recorded neural signals are connected to the computer and used as a substitute for the mouse cursor. The patient is able to hear noises indicating when their brain is thinking in a way that will allow them to focus on the cursor and move it.
In 1998, Bakay said the research was in its infancy, but that “there is tremendous potential.” Dr Kennedy, who in 2014 had a set of glass-and-gold-wire electrodes implanted beneath the surface of his own brain to further his research, explained:
“This new technique has profound implications for paralyzed people everywhere, whether paralyzed by spinal cord or brainstem injury, or by such devastating diseases as ALS. For spinal cord injured patients who have uncontrolled muscles, these neural signals could provide some control of electrical stimulators that activate the paralyzed muscles, thus bypassing the area of spinal cord injury (‘spinal bypass’). Right now, we are concentrating our efforts on the relatively easier task of providing a communication link to a computer for locked-in patients.”
Recent BCI research
Research on brain computer interfaces (BCIs) began in the 1970s, but Kennedy’s neurotrophic electrode was the first intracortical brain–computer interface. Although progress in BCI technology has been made, the biggest obstacle is the current lack of a sensor modality that provides safe, accurate and robust access to brain signals. The Annual BCI Research Award is awarded in recognition of excellence in the field of BCI research.
There have since been a number of BCI applications in humans – some more successful than others:
- In 2002, Jens Naumann, a man who was blinded in adulthood, became the first of 16 paying patients to receive a second-generation implant developed by private researcher William Dobelle. Immediately after his implant, Naumann was about to drive a car around a car park. Unfortunately, Dobelle died in 2004 before his processes and developments were documented, so when Naumann (and the other patients) began having problems with their vision, there was no solution and they eventually lost their ‘sight’ again
- Matt Nagle, a C3 tetraplegic as a result of a stabbing injury, became the first person to control an artificial hand using a BCI in 2005
- In Jun 2013 Bin He and his team at the University of Minnesota developed a non-invasive EEG based BCI to guide a remote-control helicopter through an obstacle course