BRAIN COMPUTER INTERFACES

Presented By

Sri Uday Saikia

Overview Introduction What is BCI History Structure and signals Architecture/Logical structure Brain waves Functionality Future Work Conclusion References

Introduction It is the study of brain functions. A collaboration in which a brain accepts and

controls a mechanical device. Direct communication pathway between a brain

and an external device. Thus BCI extracts electro-physical signals from

suitable components of the brain and process them to generate control signals for computers, robotic machines or communication devices.

“ A Brain-Computer Interface is a communication system that do not depend on peripheral nerves and muscles “

[J. R. Wolpaw et al. “Brain-computer interface technology: A review of the first international meeting,” IEEE Trans. Rehab. Eng., vol. 8, no. 2, pp. 164–173, 2000]

What is BCI Brain-Computer Interfaces (BCI)

◦ Interaction between the human neural system and machines

◦ Goal Enabling people (especially disabled) to

communicate and control devices by mere thinking.◦ BCI is a control system

History- Discovering the Basics 1924: Hans Berger discovers the EEG Analyses the interrelation of EEG and

brain diseases. 1970: First developments to use brain

waves as input ARPA has vision of enhanced human First step in the right direction

History-Monkey first 1990: First successful experiments with

monkeys Implanting electrode arrays into monkey

brains Recording of monkeys‘ brain waves 2000: Monkeys control robots by thoughts

History - … Humans follow More non-invasive than invasive approaches Brain reading by eg. EEG, MEG or fMRI 2004: First human benefits from research

How BCI Works?

BASIC COMPONENTS:

• Implant device

• Signal recording and processing

• External device used for control

• Feedback section to the subject

How BCI works?

• Brain is made out of neurons

• Brain detects and translates the signal of brain to tangible action

• Same principle different clearness

• More accurate signal detection from invasive BCI

PsychologicalEffort

(Intention)

Modification ofEEG Brain Signals

Signal Features

ClassificationOf Intent

appropriate feature extraction

appropriate feedback strategy

user

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Environment

Brain Computer

What is logical scheme of BCI?

Only in USA, more than 200,000 patients live with the motor consequences of serious injury.

Nicolelis, 2001

What is the motivation for BCI Research ?

Motivation for Patients: is to give disable people to communicate, to operate prostheses, and even to operate wheelchairs using brain signals

Only the INVASIVE SURGEON TECHNIQUE allows putting electrode into a very local area of a brain uniting a few neurons. These neurons could be belong to the cortex center, for example, for finger control.

BrainGate

BCI Types

Invasive BCI:implant electrodes directly onto a patient’s brain.Non-Invasive:implant medical scanning devices to read

brain signals.

Philip Kennedy and Roy Bakay (Emory University in Atlanta) were first to install a brain implant in a human that produced signals of high enough quality to simulate movement.

Implant was installed in 1998 and the patient lived long enough to start working with the implant, eventually learning to control a computer cursor.

Kennedy, P.R., Bakay R.A. (1998) Restoration of neural output from a paralysed patient by a direct brain connection. Neuroreport. ;9(8):1707-11

John P. Donoghue, et al. Assistive technology and robotic control using motor cortex ensemble-based neural interface systems in humans with tetraplegia. J Physiol 579.3 (2007) pp 603–611

10 array of electrodes, each separated by 400 μm

What is invasive technology for BCI ?

Communication

Neuroprosthetics

Environmental control

Robotics / Manipulators/ Mobility devices

Disability Level and Application: BCI for common people

Most Disable people

Health people

Applications

Honda Asimo Controll

Bionic Eye

And an artificial eye can see a lot…

Signal Processing Feature Extraction The Translation Algorithm

Output Device

Any controllable machines◦ For answering yes/no questions◦ For word processing ◦ Wheelchair◦ Virtual Reality

Usually, Computer screen and the output is the selection of targets or cursor movement

Existing Solution

Successful Story, Wearable BCI◦ A successful transition of the whole BCI system to the

portable device◦ No machine learning◦ Limited computational power (limited signal processing)

BCI2000◦ A general-purpose system for (BCI) research

Source Module (new device new driver) Signal Processing Module (reusable, No Machine Learning) User Application Module (UDP/IP support to be running in any

machine)◦ Platform

Microsoft Windows™ 2000/XP C++ language

Wearable BCI Mobility

◦ Communication technologies Bluetooth 802.11(wire less –WLAN) GSM/GPRS

◦ PDA instead of stationary computer Dry Electrode instead of wet (reducing

montage time) Making the BCI transparent

◦ No need to change electrodes for a reasonable long time

Architecture

Characteristics of BrainwavesTheta waves [4, 7.5] associated with reverie, daydreaming, meditation, creative ideas

Delta waves [0,4] Hz associated with deep sleep and in the awake state were thought to indicates physical defects in the brain.

Characteristics of BrainwavesAlpha wave(8-13hz)-its indicates both a relaxed

and attention mode of the brain. Beta wave(13-30 hz)-it is the brain wave usually associated with activity thinking, active attention.

Mu and alpha waves

CHARACTERISTICS OF BRAIN WAVES

Gamma waves-within 35Hz-it reflect the mechanism of consciousness.

Mu wave(8-12)hz –associated with Motor activity,

Functionality of BCI Steps for the function of BCI.1.user wired to a multi-electrode EEG skin cap,

which is connected to a pc running BCI2000.2.user of the signal asked to generate a series

of signals.3.EEG potential record and analyze the signal4.the software attempt to match these signal

to previous recorded signals.5.at last identified words are wrapped on

output devices like-screen or speech synthesizer.

Risk factors and alternate solutionUndergone through

hurdle brain surgery.

New surgery for each up gradation

Risky and complicated eyes surgery.

Use wearable computing devices.

External device is good option.

Glasses and Lasik operation is best options.

BCI DRAWBACKS

THE DRAWBACKS OF BCI :

- THE BRAIN IS INCREDIBLY COMPLEX,

- THE SIGNAL IS WEAK & PRONE TO INTERFENCE,

- THE EQUIPMENTS IS LESS THAN PORTABLE,

Current Projects Berlin Brain-Computer-Interface

◦ Joint Venture of several German research organisations

◦ Supported by the Ministry of Education and Research

Graz Brain-Computer-Interface◦ Wide range of research topics◦ Impressive combination of BCI and FES

(Functional Electrical Stimulation)

Future Work Virtual Reality Bluesense,Sniff mode Bluesense, Security

Conclusion• A potential therapeutic tool.

• BCI is an advancing technology promising paradigm shift in areas like Machine Control, Human Enhancement, Virtual reality and etc. So, it’s potentially high impact technology.

• Several potential applications of BCI hold promise for rehabilitation and improving performance, such as treating emotional disorders (for example, depression or anxiety), easing chronic pain, and overcoming movement disabilities due to stroke.• Will enable us to achieve singularity very soon.

• Intense R&D in future to attain intuitive efficiency.

May be in future !!!

Harder concentration to the fan to blow for simulating the ball to float

Humans dive into a virtual world by connecting their brains directly to a computer.

Star wars

Fiction or Future??

REFERENCES   [1] IEEE Xplorer Digital Library website(Through

SJCE Server) http://ieeexplore.ieee.org/Xplore  [2] Wikipedia -  internet encyclopedia

http://en.wikipedia.org/wiki/Brain-computer_interface

References

• Sixto Ortiz Jr., "Brain-Computer Interfaces: Where Human and Machine Meet," Computer, vol. 40, no. 1, pp. 17-21, Jan., 2007

• F. Babiloni, A. Cichocki, and S. Gao, eds., special issue, “Brain-Computer Interfaces: Towards Practical Implementations and Potential Applications,” ComputationalIntelligence and Neuroscience, 2007

• P. Sajda, K-R. Mueller, and K.V. Shenoy, eds., special issue, “Brain Computer Interfaces,” IEEE Signal Processing Magazine,Jan. 2008

• The MIT Press – “Toward Brain-Computer Interfacing”

• Wikipedia, HowStuffWorks and various other website sources…