Imagine having the ability to turn on the television and change the channel without using a remote control. Or better yet, imagine navigating the internet and sending emails using just the power of your thoughts. Although it may sounds like something out of a science fiction movie, these ideas are becoming a reality. The brain-computer interface is the next technological achievement that blurs the line between science fiction and scientific reality.

What is the brain computer interface (BCI)?

BCI encompasses a wide range of technological ideas that allow our brains to directly communicate and control external devices via a computer. It is well-established that our brain transmits signals via electrical impulses (whether it be signals that control limb movement or signals that encode the color of a flower). These electrical impulses are recorded by electrodes placed either on the scalp or within the brain tissue, and converted into binary signals that can be interpreted by computer programs. These computer programs use the decoded signal to control a wheelchair, a mouse on a computer screen or even a robotic arm that can grasp objects. Alternatively, the BCI can work in the opposite direction. Signals generated by a computer can be converted to electrical impulses and sent to the brain. The brain then interprets these impulses as a smell, a color, a movement or even a visual outline. Either way, the BCI is the first technology to directly utilize the electrical signals generated by the brain tissue to control external devices and vice versa.

The importance of BCI devices

At first thought, spending large amounts of money for a device that can be thought of as an interactive video game may seem superfluous. However, this technology may afford severely disabled persons the opportunity to communicate while simultaneously restoring their independence and mobility. Conditions such as amyotrophic lateral sclerosis (ALS or more commonly Lou Gehrig’s Disease), muscular dystrophy and spinal cord injury often leave individuals without the ability to move, while their cognitive function is unaffected. Persons with ALS, muscular dystrophy and spinal cord injury are still capable of creating motor plans within the cerebral cortex, although the signals are not transmitted to the muscles. Scientists are working to capture the signals created in the cortex and utilizing them to control external devices.

BCI – where are we now?

Although the concept has been around for nearly 40 years, scientists have made significant advancements in BCI technology over the past 10 years. BCI technology has recently been used to drive a robotic arm for self-feeding in a monkey. The animal was initially trained using a joystick to control the robotic arm. The joystick was eventually weaned and motor activity from the cortex was recorded via an implanted electrode. Signals from the cortex were decoded in real-time to control the movement of the robotic arm. The monkey was then able to feed himself via the robotic arm, using only his conscious thought.

While these trials are impressive, they are not the focus of the majority of BCI research. The next most important step is creating devices that improve functional ability in humans with disabilities. Researchers at Brown University are currently conducting clinical trials in humans with the ultimate goal of restoring “the communication, mobility and independence of people with severe paralysis.” BCI devices that acquire signals through EEG technology or implanted invasive techniques are currently being used by disabled individuals to control wheelchairs, type on a computer and even send text messages.

While the media has glorified the use of BCI devices, there are many limitations to the current BCI technology. In order to make BCI devices a tangible reality for a large portion of persons with disabilities, specific roadblocks need to be passed. The current technology permits only a few words per minute to be “typed” using BCI devices. The speed and accuracy of the decoding and signal analysis would need to be greatly enhanced to permit real-time communication. The current technology is also limited the BCI control of robotic extremities to small movements in a confined space. For a practical real-world application, the methodology and timing of signal extraction would need to be improved vastly beyond the present day possibilities. To date, much of the BCI devices are operated in research settings, with few practical devices being used outside of the laboratory. The goal of many scientists working on the technology is to create user-friendly devices that can be operated in an individual’s home without supervision. Presently, there are very few of these types of devices available.

The future of BCI

The future for BCI technology is boundless. This technology will offer future generations with disabilities the ability to communicate and interact with their environment in ways that we have viewed as impossible for millennia. In addition to restoring mobility to disabled persons, the technology also offers a potential method to overcome blindness, deafness and other sensory-affected conditions. In a world that is continually more “plugged in” day after day, the exchange of information has become nearly completely digital. This environment fosters the development of BCI technology and continues to expand the possibilities of BCI applications.

References

Hochberg, Leigh. Hope for people with paralysis. Brain-Computer Interface, Developed at Brown, Begins New Clinical Trial. Brown University Press Release. Jun 10 2009.

Birbaumer N. Brain-computer-interface research: coming of age. Clin Neurophysiol. Mar 2006;117(3):479-483. doi:10.1016/j.clinph.2005.11.002

Vaughan TM, Heetderks WJ, Trejo LJ, et al. Brain-computer interface technology: a review of the Second International Meeting. IEEE Trans Neural Syst Rehabil Eng. Jun 2003;11(2):94-109. doi:10.1109/TNSRE.2003.814799

Velliste M, Perel S, Spalding MC, Whitford AS, & Schwartz AB (2998). Cortical control of a prosthetic arm for self-feeding Nature, 453 (7198), 1098-1101 DOI: 10.1038/nature06996