2. CONTENTS
INTRODUCTION
WHAT IS BCI?
HOW DOES ITWORK?
HUMAN BRAIN
SIGNALACQUISITION
SIGNAL PROCESSING
EXTERNEL DEVICES
DISADVANTAGE
CONCLUSION
6. BRAIN COMPUTER INTERFACE
Brain -Computer Interface
-Direct Neural Interface or Brain-Machine
Interface
Direct communication pathway between a
brain and an external device.
7. How does it work?
SignalAcquisition
Signal Processing
Devices
9. Brain Waves
Type Frequency Location Use
Delta <4 Hz Everywhere occur during sleep, coma
Theta 4-7 Hz temporal and parietal correlated with emotional stress
(frustration & disappointment)
Alpha 8-12 Hz occipital and parietal reduce amplitude with sensory
stimulation or mental imagery
Beta 12-36 Hz parietal and frontal can increase amplitude during
intense mental activity
Mu 9-11 Hz frontal (motor cortex) diminishes with movement or
intention of movement
Lambda sharp, jagged Occipital correlated with visual attention
Vertex higher incidence in patients with
epilepsy or encephalopathy
10. SIGNAL ACQUISITION
EEG(ELECTROENCHEPHALOGRAPHY)
Measurements of electrical activity of the brain .
The basic frequency of the EEG range is classified into five bands for
purposes of EEG analysis called brain rhythms.
Band Frequency [Hz]
Delta 0.5- 4
Theta 4- 8
Alpha 8- 13
Beta 13- 22
Gamma 22-30
11. THE TWO TYPES OF BCI
Invasive BCIs
Non-Invasive BCIs
16. Spike Detection
transmit only the action potential waveforms
This compression reduces the transmitted
data rate per channel
implemented using an application-specific
integrated circuit (ASIC) with limited
computational resources.
17. Signal Analysis
Feature extraction and classification of EEG
are dealt in this section.
form distinct set of features for each mental
task.
The features extracted in the previous stage
are the input for the classifier.
18. EXTERNAL DEVICES
MOVEMENTOF A CURSOR,ROBOTIC LIMB,WHEELCHAIR
TYPING ,DIALINGA PHONE NUMBER
PLAYINGGAMES,CHANGINGATV CHANNEL etc….
21. CONCLUSION
“No more handicap people (Synthetic arms, legs, eye,
sensitive skin etc.) !”
What happens when humans merge with machines?The
question is not what will the computer be like in the future,
but instead, what will we be like?What kind of people are
we becoming?