A brain computer interface (BCI) is a device that allows people with cognitive or motor limitations to control computers and other devices. BCIs make use of different combinations of sensors, recording techniques, signal-processing algorithms, and machine learning to translate brain signals into operating commands. They can operate a wide array of devices, from cursors on computers to wheelchairs and robotic arms.
Most linking the human mind to a machine BCIs measure activity from the scalp, such as electroencephalographic (EEG) or functional near-infrared imaging (fNIRS) signaling. The signals are recorded by a sensor that detects the activity of neuronal neurons. Software then converts these signals to operating commands.
In a variety of BCI systems, the user has to go through an iterative training process to master the ability to produce signals that can be recognized by the system. For instance the BCI designed to type letters requires the user to imagine the movement of their left or right hand to produce the desired image of movement.
The most exciting BCI innovations are implantable or invasible devices that record directly on the neural tissue, rather than scalp. These devices are more precise than noninvasive BCIs but they require surgical intervention and carry some potential risks.
BCIs that are invasive are still in the early stages of development and patients should be aware of the risks and advantages. BCIs can detect neural signals containing sensitive information about health and behavior. Security of data and privacy is an additional issue. Some people are opposed to the technology due to fears that hackers can gain access to their minds and manage them.