Pratishruti Jain Presented by: Gunjan Maloo B.Tech(CSE) II SEM
What is Brain-Computer Interface?
Principle behind BCI
Objective of BCI
Types of BCIs
Software behind BCI
What is Brain-Computer Interface?
Brain Computer Interface is a direct technological interface between a brain & a computer system not requires a motor output from the user.
It is abbreviated as BCI.
It is also known as Direct Neural Interface (DNI) &
Brain – Machine Interface (BMI).
Brain-computer interface is an
electrode chip which can be
implemented in the brain through
When it is implemented in brain
the electrical signal exchanged by
neurons within the brain are sent to the
computer and then the computer is
controlled by person.
Principle Behind BCI
This technology is based on to sense, transmit, analyze and apply the language of neurons.
It consist of a sensor that is implanted in the motor cortex of the brain and a device that analyses brain signals. The signals generated by brain are interpreted and translated into cursor movement on computer screen to control the computer.
It consists of a silicon array about the size of an Aspirin tablet that contains about 100 electrodes each thinner than a human hair.
BCI vs Neuroprosthetics
Neuroprosthetics typically connect the nervous system to a device, whereas BCIs usually connect the nervous system with a computer system.
Practical neuroprosthetics can be linked to any part of the nervous system—for example, peripheral nerves
While the term "BCI" usually designates a narrower class of systems which interface with the central nervous system.
Objective of BCI:
The goal of the Brain-Computer Interface is to develop a fast and reliable connection between the brain of a severely disabled person and a personal computer .
The ‘Brain Gate’ device can provide paralysed or motor-impaired patients a mode of communication through the translation of thought into direct computer control.
Types of BCIs:
Invasive BCIs are implanted directly into the grey matter of the brain during neurosurgery.
Non Invasive BCI
Non-Invasive BCIs do not involve neurosurgery. They are just like wearable virtual reality devices.
Partially Invasive BCI
Partially invasive BCI devices are implanted inside the skull but rest outside the brain rather than within the grey matter.
History of BCI:
Research on BCIs has been going on for more than 20 years, but from the mid-1990s there has been a dramatic increase in working experimental implants.
Brain-Computer Interface was commercially developed by the bio-tech company Cyberkinetics in 2003 in conjunction with the Department of Neuroscience at Brown University.
BCI Research On Animals:
At first, rats were implanted
with BCI .
Signals recorded from the
cerebral cortex of rat operate
BCI to carry out the movement.
Researchers at the University
of Pittsburgh had demonstrated
on a monkey that can feed itself
with a robotic arm simply by
using signals from its brain.
Next Step- HUMANS!!
BCI On HUMANS
In December 7, 2004, brain-computer interface had been clinically tested on a human by an American biotech company Cyberkinetics.
The first participant in these trials was a 25-year-old man who had sustained a spinal cord injury leading to paralysis in all four limbs .
Over a period of nine months, he
took part in 57 sessions during
which the implanted Brain Gate
sensor recorded activity in his
motor cortex region while he
imagined moving his paralyzed
limbs and then used that imagined
motion for several computer-
based tasks such as, moving a
computer cursor to open e-mail,
draw shapes and play simple video
How BCI Implements?
A more difficult task is interpreting the brain signals for movement in someone who can't physically move his own arm. With a task like that, the subject must "train" to use the device.
With an implant in place, the subject would visualize closing his or her disabled hand. After many trials, the software can learn to recognize the signals associated with the thought of hand-closing.
Software connected to a robotic hand is programmed to receive the "close hand" signal and interpret it to mean that the robotic hand should close. At that point, when the subject thinks about closing the hand, the signals are sent and the robotic hand closes.
This could even be accomplished without the "robotic" part of the device. Signals could be sent to the appropriate motor control nerves in the hands, bypassing a damaged section of the spinal cord and allowing actual movement of the subject's own hands.
Software behind BCI
The technology is comprised of four main components; a signal capture system, a signal processing system, a pattern recognition system, and a device control system.
The signal capture system includes the electrodes themselves and the isolated electronic amplifiers
The signal processing system includes the algorithms for the linear prediction of the signal.
The pattern recognition system often used to be composed of neural networks as to recognize which neurons are producing these signals.
Interfaces have been developed to control different devices .
Brain - Computer Interface
One of the most exciting areas of BCI research is the development of devices that can be controlled by thoughts.
For a quadriplegic, something as basic as controlling a computer cursor via mental commands would represent a revolutionary improvement in quality of life.
Some of the applications of this technology are also frivolous, such as the ability to control a video game by thought , ability to change TV channels with your mind etc.
At present ,the biggest impediment of BCI technology is the lack of sensor modality that provides safe, accurate, and robust access to brain signals.
It is very expensive.
Information transformation rate is limited to 20 bits/min.
Difficulty in adaptation and learning.
Light Reactive Imaging BCI devices are still in the realm of theory.
This would involve implanting a laser inside the skull.
The laser would be focussed on a single neuron and the neuron’s reflectance is measured by a separate sensor.
When the neuron fires, the light pattern and wavelength it reflects would change slightly . This would allow the researchers to monitor a single neuron and require less contact with the tissue.
Researchers of the Carleton University , Canada believe that the same interface could form the basis of a mind-controlled password system.
The results of BCI are spectacular and almost
BCI can help paralyzed people to move by controlling their
own electric wheelchairs, to communicate by using e-mail and
Internet-based phone systems, and to be independent by
controlling items such as televisions and electrical appliances.
Conclusively, BCI has proved to be a boon for paralyzed