Brain-Computer Interface (BCI) and Applications
Brain Computer Interfaces (BCI) provide a technology to connect your brain with a device, like a computer. The major applications include restoration of impaired parts of the brain, replacement of limbs with neuroprosthetics, enhancement of computer gaming, supplementation to augmented reality/VR devices, improvement in motor and cognitive functioning, and research to understand the brain by decoding brain activity.
The mechanisms are either invasive, through intracortical electrodes, or non-invasive, such as skull caps for EEG. The former is faster, more effective for motor impairments and has a better signal-to-noise ratio but it comes at the cost of neurosurgery to implant electrodes and the complications that may arise.
BCI systems can be categorized by the way they use the brain: Passive BCI decode unintentional emotional and cognitive states of the brain, while active BCI involve the user’s voluntary, intentional brain activity. Reactive BCI use brain signals generated as a response to external stiumuli.
Passive BCI, for example, is applied in detecting a driver’s drowsiness to prevent accidents. Active BCI can be seen in systems utilizing users’ intentional motor imagery (MI), which is the imagination of how one would move. Reactive BCI may involve studying visually evoked P300 signals in the brain produced after seeing a target external stimuli.
Psychological factors such as attention, memory load, fatigue, and competing cognitive processes, and basic characteristics such as lifestyle, gender, and age influence one’s instantaneous brain dynamics.
BCI technologies, assissted by machine learning, can decode neural activities, and deliver external signals into targeted brain areas to induce neuroplasticity, the remodeling of neurosynaptic organization.
A bidirectional BCI framework can be used for direct brain-to-brain communication. This may perhaps be the future of texting. Brain signals can also be translated to drive wheelchairs and control robots. BCI has been used in sending a humanoid robot to a coal mine for executing a task that is potentially unsafe for a human.
BCI systems increase proficiency in controlling neuroprosthetics, devices that enhance the output of the nervous system. Stimulation of certain regions of the brain with intracortical electrodes can be used to regain motor control. Experiments testing BCI on a tetraplegic patient show better performance in grasping with a prosthetic arm.
BCI is a great tool to investigate emotional states to understand decision-making. Aggregation of information from two intelligence analysts’ brain signals may lead to better decision making than one’s brain signals.
Brain painting allows a user to draw lines in a virtual canvas by brain signals, which gives an alternative communication channel for people with paralysis. BCI-driven systems could be practical for improving astronauts’ functionality, efficiency and safety given the lack of gravity.
Biofeedback training has been used successfully to treat health problems such as migraine headaches, hypertension, Attention Deficit Hyperactive Disorder (ADHD), etc. Neurofeedback (biofeedback using signals measured from the brain) can be used to alter the brain activity and cultivate attention.
BCI can also be used for gaming. MindBalance, for example, involves the user paying atention to a side of the tightrope to balance an avatar walking on it. In another game, attention was rewarded by a more responsive BCI-connected controller.
Another game involves the user looking at one of 4 orthogonal directions, represented in the form of yellow blocks, to move a character closer to its bait, shown in red in the image below.
BCI technologies are remarkable for research, accessibility, and recreation. I look forward to their advancements and popularization.
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