How Does Brain-Computer Interfaces Work?
Neurons send signals across synapses to each other. If the voltage changes by a large amount over a short interval, receiving neuron sends an electrical chemical pulse called Action Potential.
- Electrodes can measure the Action Potential with miniature metal needles that record voltage change
Interface Training
- A person would watch videos of certain actions/movements, the electrodes would measure the Action Potential of the person at that moment.
- Machine learning algorithm then recognizes patterns and start outputting command whenever similar Action Potentials are detected.
- Reverse direction work too → computer receives input (a touch on prosthetics), computer reverse engineers the input into Action Potential patterns, computer outputs the pattern to the electrodes and causes person to feel the touch
Electroencephalography (EEG)
- Detects and records electrical activities in the brain
Non-Invasive Electromyographic Signals (EMG)
- Measures electrical currents generated in muscles during its contraction representing neuromuscular activities
Semi-Invasive Electrocorticography (ECoG)
- Uses electrodes placed directly on the surface of the brain to record electrical activity
Startups in BCI
- Nextmind, Neurable, Ctrl Labs (acquired by Facebook in 2018), Valve, Paradromics, Kernel, Synchron, InterXon (Muse)
Applications of BCIs:
Motor Neuroprosthetics
- Devices that translate user thought into movements of prosthetic limbs
Internet Surfing
- Receive and enter information into the computer using only thoughts
Video Games w/ VR
- If we can allow players to be fully immersed in the Metaverse while feeling sensations as well, we are able to transcend human existence as we know it
Brain to Brain Interface (BTBI)
- Allow us to essentially download memories as files and send them to recipients
Lie Detectors
- Measuring unconsciously generated p300 signals