02-04-2011, 12:00 PM
Presented by:
ANKITA APARAJITA
[attachment=11549]
Brain Fingerprinting is designed to determine whether an individual
recognizes specific information related to an event or activity by measuring
electrical brain wave responses to words, phrases, or pictures presented on a computer screen. The technique can be applied only in situations where investigators have a sufficient amount of specific information about an event or activity that would be known only to the perpetrator and investigator.
TECHNIQUE
The technique uses the well known fact that an electrical signal known as P300 is emitted from an individual's brain approximately 300 milliseconds after it is confronted with a stimulus of special significance, e.g. a rare vs. a common stimuls or a stimulas the proband is asked to count. The novel interpretation in brain fingerprinting is to look for P300 as
response to stimuli related to the crime in question e.g., a murder weapon or a victim's face. Because it is based on EEG signals, the system does not require the testee to issue verbal responses to questions or stimuli.
PHASES OF FARWELL BRAIN FINGERPRINTING
1.Crime Scene Evidence Collection;
2. Brain Evidence Collection;
3. Computer Evidence Analysis; and
4. Scientific Result.
The MERMER includes:
. The P300 -an electrically positive component maximal at the parietal scalp site
2. Another, longer latency, electrically negative subcomponent prominent at the frontal scalp site
3. Phasic changes in the frequency and structure of the signal.
Types of Stimuli Used
• Probes
– Life-experience related
– Relevant to the investigated event -recognizable and noteworthy only for the subjects who had participated in the event (MERMER)
– Indistinguishable from the Irrelevants for a subject who is not knowledgeable about the situation under investigation
• Targets
– Push a button to indicate known image
– Since the relatively rare Targets are singled out in the task being performed, the Targets are noteworthy for the subject, and each Target stimulus elicits a MERMER
• Irrelevant Stimuli
– information relevant to the crime that the suspect claims to have no knowledge of
ANKITA APARAJITA
[attachment=11549]
Brain Fingerprinting is designed to determine whether an individual
recognizes specific information related to an event or activity by measuring
electrical brain wave responses to words, phrases, or pictures presented on a computer screen. The technique can be applied only in situations where investigators have a sufficient amount of specific information about an event or activity that would be known only to the perpetrator and investigator.
TECHNIQUE
The technique uses the well known fact that an electrical signal known as P300 is emitted from an individual's brain approximately 300 milliseconds after it is confronted with a stimulus of special significance, e.g. a rare vs. a common stimuls or a stimulas the proband is asked to count. The novel interpretation in brain fingerprinting is to look for P300 as
response to stimuli related to the crime in question e.g., a murder weapon or a victim's face. Because it is based on EEG signals, the system does not require the testee to issue verbal responses to questions or stimuli.
PHASES OF FARWELL BRAIN FINGERPRINTING
1.Crime Scene Evidence Collection;
2. Brain Evidence Collection;
3. Computer Evidence Analysis; and
4. Scientific Result.
The MERMER includes:
. The P300 -an electrically positive component maximal at the parietal scalp site
2. Another, longer latency, electrically negative subcomponent prominent at the frontal scalp site
3. Phasic changes in the frequency and structure of the signal.
Types of Stimuli Used
• Probes
– Life-experience related
– Relevant to the investigated event -recognizable and noteworthy only for the subjects who had participated in the event (MERMER)
– Indistinguishable from the Irrelevants for a subject who is not knowledgeable about the situation under investigation
• Targets
– Push a button to indicate known image
– Since the relatively rare Targets are singled out in the task being performed, the Targets are noteworthy for the subject, and each Target stimulus elicits a MERMER
• Irrelevant Stimuli
– information relevant to the crime that the suspect claims to have no knowledge of
