A brain-computer interface (BCI) enables direct communication between the brain and mechanical devices, allowing motor-impaired patients to control them through thought. Key developments have included the 'Braingate' device, which converts neural signals into computer commands, as well as research into BCIs for robotic manipulation. While BCIs show promise in medical and military applications, challenges remain, including signal weakness and equipment bulkiness.

1. BRAIN COMPUTER
INTERFACE

2. DEFINITION
A Brain Computer
Interface (BCI) is a
collaboration in which
a brain accepts and
controls a mechanical
device as a natural part
of its representation of
the body.

3. GENERAL PRINCIPLE
(a)
(b)
(c)
(a) In healthy subjects, primary motor area sends movement
commands to muscles via spinal cord.
(b) In paralyzed people this pathway is interrupted.
(c) Computer based decoder translates this activity into
commands for muscle control.

4. BACKGROUND
Signals from an array of
neurons read.
Cerebral electric activity
recorded.
Signals are amplified.
Transmitted to computer
Transformed to device
control commands.
Using computer chips and
programs.
Signals translated into
action.

6. BASIC COMPONENTS
The implant device,
or chronic multielectrode array
The signal recording
and processing
section
An external device
A feedback section to
the subject

7. Development of BCI
Early work
Algorithms to reconstruct movements from motor cortex
neurons, which control movement were developed in 1970s.
The first Intra-Cortical Brain-Computer Interface was built by
implanting neurotrophiccone electrodes into monkeys.
After conducting initial studies in rats during the 1990s, researchers
developed Brain Computer Interfaces that decoded brain activity in
monkeys and used the devices to reproduce monkey movements in
robotic arms.
Present Developments
BCI for Tereaplegics
Brain controlled Robot
`BRAINGATE' BCI
ATR and HONDA's new BCI
BCI2000

8. BCI for Tetraplegics
6- channel EEG BCI used.
Sensory & motor cortices
activated during attempts.
Control scheme sends
movement intention to
Prosthetic Controller.
Prosthetic returns force
sensory information to
Controller.
Feedback processed and
grip is adjusted.

9. BRAIN CONTROLLED ROBOTS
Robot hand mimics subject's
finger movements.
Signals extracted and
decoded by computer
program.
Transferred to hand shaped
robot.
To simulate original
movement performed.
Robot executes commands
using onboard sensor
readings.

10. `BRAINGATE'
BCI
The `Braingate' device can provide motor-impaired patients a
mode of communication through the translation of thought into
direct computer control.

11. FEATURES OF BRAINGATE BCI
Neural Interface Device.
Consists of signal sensor and
external processors.
Converts neural signals to output
signals.
Sensor consists of tiny chip with
electrode sensors.
Chip implanted on brain surface.
Cable connects sensor to external
signal processor.
Create communication o/p using
decoding software.

12. ATR & HONDA DEVELOP NEW BCI
BCI for manipulating
robots using brain signals.
Enables decoding natural
brain activity.
MRI based neural decoding.
No invasive incision of
head and Brain.
By tracking haemodynamic
responses in brain.
Accuracy of 85%

13. BCI APPLICATIONS
Medical applications(restoration of a
communication channel for patients with lockedin syndrome and the control of neuroprostheses
in patients affected by spinal cord injuries )
Military applications
Counter terrorism(10 times faster image
search)
multimedia and virtual reality applications

14. DRAWBACKS
EEGs measure tiny voltage potentials. The
signal is weak and prone to interference.
Each neuron is constantly sending and
receiving signals through a complex web
of connections. There are chemical
processes involved as well, which EEGs
can't pick up on.
The equipment heavy(~10 lbs.) & hence
not portable.

15. COMPUTATIONAL CHALLENGES
AND
FUTURE IMPLEMENTATIONS
Minimally invasive surgical methods.
Next generation Neuroprosthesis.
Vision prosthesis.
BCI for totally paralyzed.
Minimal number of calibration trials.
Development of telemetry chip to collect
data without external cables.

16. CONCLUSION
A potential therapeutic
tool.
BCI System is nominated for
European ICT Grand Prize.
the
Potentially high impact technology.

17. Thank you