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Presented by:
LAKSHMY.J
Brain Fingerprinting Technology
TOPIC OUTLINE
1. Introduction
2. Working Principle
3. Scientific Procedure
4. Equipments and Technology
5. Algorithm used
6. EEG measurement
7. Applications
8. Disadvantages
9. Conclusions
10. References
INTRODUCTION
Invented by Dr. Farwell
Proved successful over 170 cases
Computer based technique that measures recognition of familiar stimuli by measuring electrical brain wave responses to words, phrases, or pictures that are presented on a computer screen
WORKING PRINCIPLE
Entire system under computer control includes
Presentation of the stimuli
Recording of electrical brain activity
Determination of "information present" or "information absent,"
Mathematical data analysis algorithm that compares the responses
statistical confidence level for the determination.
When someone commits a crime, his brain records it in the memory .
BFP seeks to reveals that memory, by showing the suspect, evidences taken from the crime scene.
A head band with EEG sensors is placed on the subject which digitizes brain wave activity and feeds it to the computer.
The computer records the brain waves produced in response to what the subject sees which are called as Event Related Potentials (ERP)
On seeing familiar info p300,a positive electric voltage is elicited for 300ms by the brain which is recorded as a wave form.
P300 along with along with other electrically negative components constitutes the MERMER (Memory and Encoding Related Multifaceted Electroencephalographic Response)
By analyzing MERMER the pattern of waves using suitable computer based algorithm, it can be determined if the subject is recognizing what he is seeing.
Accuracy lies in the ability to differentiate p300 brain wave, before the suspect has time to affect the output.
SCIENTIFIC PROCEDURE
Stimulus appears for a fraction of a second when they are presented on a video monitor under computer control.
Three types of stimuli are presented:
I ) Targets,
2 ) Irrelevants, and
3 ) probes.
TARGETS stimuli
Info known to suspect about the crime
Elicits a MERMER
IRRELEVANTS stimuli
Info not related to the crime
Do not elicit a MERMER
PROBES stimuli
Info relevant to the situation under investigation that only the perpetrators knows
Elicits a MERMER
Stimuli consists of 1/6 targets, 1/6 probes and 2/3 irrelevents.
Comparing “Probe” with the “Target” determines if the subject recognizes the Probes
Comparing the “Probe” with the “Irrelevant” determines if the subject does not recognizes the Probes.
EQUIPMENTS AND TECHNOLOGY
The BFP system comprises
A personal computer
A data acquisition board
A graphics card for driving two monitors from one PC
A 4 channel EEG amplifier system
Software for data acquisition and analysis
Electrodes
ALGORITHM USED
Nonparametric statistical method called Bootstrapping compares the responses produced by the stimuli.
It deduces the distribution of a statistic from a sample
Determines how reliable that statistic is as a measure for the population.
EEG MEASUREMENT
Functional activities emerging from the brain is reflected by the variation of the surface potential distribution on the scalp.
When a stimulus appears, the EEG breaks into a series of larger peaks and troughs which constitutes the ERP
Voltage difference between a pair of electrodes are measured, filtered, amplified and recorded for analysis.
APPLICATIONS
National Security
Aids in determining who has participated in terrorist acts, directly or indirectly.
Aids in identifying trained terrorists with the potential to commit future terrorist acts, even if they are in a “sleeper” cell and have not been active for years.
To test job applicants on the falsification of an application.
Medical Field
Helps in detecting diseases such as Alzheimer's
Evaluation of the effectiveness of the treatment
Helps in Identifying false-witnesses
Successfully predict learning difficulties
Advertising area
What specific information do people retain from advertising
which element have more impact
Which type of media is most effective
What commercial is most effective for a single product
Criminal Justice
Improves speed and accuracy
Reduces time and cost
DISADVANTAGES
Not applicable for general screening.
It does not indicate intent of the crime.
Takes a fair amount of time to set up and conduct properly .
Difficult to distinguish the criminal and a witness who saw all the criminal activity happen.
CONSLUSIONS
BFP is a new technology which provides high rate accuracy results
Introduction of this technology, decreases the crime rates in the future to a considerate extend.
It is fully developed and is available for application in the field.