Brain Finger Printing
Garima Singh (57/CSE/7th Sem)
Department Of Computer Science Engineering
Guru Tegh Bahadur Institute of Technology
Table of Contents
3.2. Sources of EEG Activities
3.3. EEG Vs MRI & PET
5. Role of Brain-Fingerprinting in Criminal Proceeding
5.1. Phase 1:Invetigation
5.2. Phase 2:Interview of the Subject
5.3. Phase 3:Scientific Testing with Brain Fingerprinting
5.4. Phase 4:Adjudication of Guilt or Innocence
5.5. Role of science in Legal Proceedings
6. Current Uses and Application
6.1. Medical Application
6.2. Advertising Application
6.3. Security Testing
7. Limitations of Brain-Fingerprinting
Brain Fingerprinting was developed and patented in 1995 by Lawrence A. Farwell,
Ph.D., chairman of the Brain Wave Institute in Fairfield, Iowa, and former Harvard
University research associate. Brain fingerprinting is based on the theory that throughout
any action, the brain plans, records, and executes all of the actions. Such details, all
concealed within the brain, can now be revealed through brain fingerprinting. This
technique measures how brain waves respond to specific words or pictures flashed across
a screen. Pictures, both relevant and irrelevant to the actions, are shown. The relevant
images should trigger memories of subject.
"Brain Fingerprinting" is a controversial forensic science technique that determines
whether specific information is stored in a subject’s brain by measuring electrical
brainwave responses to words, phrases, or pictures that are presented on a computer
screen. Brain fingerprinting was invented by Lawrence Farwell. The theory is that the
brain processes known, relevant information differently than it processes unknown or
Brain fingerprinting involves measuring the MERMER paradigm EEG response during
interrogation. MERMER is Memory and Encoding Related Multifaceted
Electroencephalography Responses. The brain print is based on the P300 complex, a
series of well-known brainwave components that can be measured. The technique is said
to be more effective than a lie detector test.
The technique uses the well known fact that an electrical signal known as P300 is emitted
from an individual's brain beginning approximately 300 milliseconds after it is confronted
with a stimulus of special significance, e.g. a rare vs. a common stimulus or a stimulus the
subject is asked to count. The application of this in brain fingerprinting is to detect the P300
as a response to stimuli related to the crime or other investigated situation, e.g., a murder
weapon, victim's face, or knowledge of the internal workings of a terrorist cell. Because it is
based on EEG signals, the system does not require the subject to issue verbal responses to
questions or stimuli.
The person to be tested wears a special headband with electronic sensors that measure the
EEG from several locations on the scalp. The subject views stimuli consisting of words,
phrases, or pictures presented on a computer screen. Stimuli are of three types:
1) “irrelevant” stimuli that are irrelevant to the investigated situation and to the test subject,
2) “target” stimuli that are relevant to the investigated situation and are known to the subject,
3) “probe” stimuli that are relevant to the investigated situation and that the subject denies
Probes contain information that is known only to the perpetrator and investigators and not to
the general public or to an innocent suspect who was not at the scene of the crime. Before the
test, the scientist identifies the targets to the subject, and makes sure that he/she knows these
relevant stimuli. The scientist also makes sure that the subject does not know the probes for
any reason unrelated to the crime, and that the subject denies knowing the probes. The
subject is told why the probes are significant (e.g., “You will see several items, one of which
is the murder weapon”), but is not told which items are the probes and which are irrelevant.
Since brain fingerprinting uses cognitive brain responses, brain fingerprinting does not
depend on the emotions of the subject, nor is it affected by emotional responses. Brain
fingerprinting is fundamentally different from the polygraph (lie-detector), which measures
emotion-based physiological signals such as heart rate, sweating, and blood pressure. Also,
unlike polygraph testing, it does not attempt to determine whether or not the subject is lying
or telling the truth. Rather, it measures the subject’s brain response to relevant words,
phrases, or pictures to detect whether or not the relevant information is stored in the subject’s
By comparing the responses to the different types of stimuli, the brain fingerprinting system
mathematically computes a determination of “information present” (the subject knows the
crime-relevant information contained in the probe stimuli) or “information absent” (the
subject does not know the information) and a statistical confidence for the determination.
This determination is mathematically computed, and does not involve the subjective
judgment of the scientist.
A suspect is provided with information as follows :
Information the suspect is expected to know
Information suspect shouldn’t know
Information of crime that only perpetrator would know
Fig. 1: Not Guilty
Fig. 2: Guilty
Electroencephalography (EEG) is the measurement of electrical activity produced by the
brain as recorded from electrodes placed on the scalp.
Just as the activity in a computer can be understood on multiple levels, from the activity
of individual transistors to the function of applications, so can the electrical activity of
the brain be described on relatively small to relatively large scales. At one end are action
potentials in a single axon or currents within a single dendrite of a single neuron, and at
the other end is the activity measured by the EEG which aggregates the electric voltage
fields from millions of neurons. So-called scalp EEG is collected from tens to hundreds
of electrodes positioned on different locations at the surface of the head. EEG signals (in
the range of milli-volts) are amplified and digitalized for later processing. The data
measured by the scalp EEG are used for clinical and research purposes.
3.2.Source of EEG Activity
Scalp EEG activity oscillates at multiple frequencies having different characteristic
spatial distributions associated with different states of brain functioning such as waking
and sleeping. These oscillations represent synchronized activity over a network of
neurons. The neuronal networks underlying some of these oscillations are understood
(such as the thalamocortical resonance underlying sleep spindles) while many others are
not (e.g. the system that generates the posterior basic rhythm).
3.3.EEG vs fMRI and PET
EEG has several strong sides as a tool of exploring brain activity; for example, its time
resolution is very high (on the level of a single millisecond). Other methods of looking at
brain activity, such as PET and fMRI have time resolution between seconds and minutes.
EEG measures the brain's electrical activity directly, while other methods record changes
in blood flow (e.g., SPECT, fMRI) or metabolic activity (e.g., PET), which are indirect
markers of brain electrical activity.
EEG can be used simultaneously with fMRI so that high-temporal-resolution data can be
recorded at the same time as high-spatial-resolution data, however, since the data
derived from each occurs over a different time course, the data sets do not necessarily
represent the exact same brain activity. There are technical difficulties associated with
combining these two modalities like currents can be induced in moving EEG electrode
wires due to the magnetic field of the MRI.
EEG can be recorded at the same time as MEG so that data from these complimentary
high-time-resolution techniques can be combined. Magneto-encephalography (MEG) is
an imaging technique used to measure the magnetic fields produced by electrical activity
in the brain via extremely sensitive devices such as superconducting quantum
interference devices (SQUIDs). These measurements are commonly used in both
research and clinical settings. There are many uses for the MEG, including assisting
surgeons in localizing pathology, assisting researchers in determining the function of
various parts of the brain, neuro-feedback, and others.
Scalp EEG, the recording is obtained by placing electrodes on the scalp. Each electrode
is connected to one input of a differential amplifier and a common system reference
electrode is connected to the other input of each differential amplifier.
These amplifiers amplify the voltage between the active electrode and the reference
(typically 1,000–100,000 times, or 60–100 dB of voltage gain). A typical adult human
EEG signal is about 10µV to 100 µV in amplitude when measured from the scalp 
and is about 10–20 mV when measured from subdural electrodes.
In digital EEG systems, the amplified signal is digitized via an analog-to-digital
converter, after being passed through an anti-aliasing filter.
Since an EEG voltage signal represents a difference between the voltages at two
electrodes, the display of the EEG for the reading encephalographer may be set up in one
of several ways.
The P300 (P3) wave is an event related potential (ERP) which can be recorded via
electroencephalography (EEG) as a positive deflection in voltage at a latency of roughly
300 ms in the EEG. The signal is typically measured most strongly by the electrodes
covering the parietal lobe. The presence, magnitude, topography and time of this signal
are often used as metrics of cognitive function in decision making processes. While the
neural substrates of this ERP still remain hazy, the reproducibility of this signal makes it
a common choice for psychological tests in both the clinic and laboratory.
The P300 signal is an aggregate recording from a great many neurons. Although
typically non-invasive, parts of the signal may be sampled more directly from certain
brain regions via electrode (hence, the medial temporal P300 or MTL-P300). This
methodology allows for isolation and local recording of one area without the noise from
other signals acquired through scalp electrodes . In practice, the P300 waveform must
be evoked using a stimulus delivered by one of the sensory modalities. One typical
procedure is the 'oddball' paradigm, whereby a target stimulus is presented amongst
more frequent standard background stimuli. A distracter stimulus may also be used to
ensure that the response is due to the target rather than the change from a background
pattern. The classic oddball paradigm has seen many variations, but in the end most
protocols used to evoke the P300 involve some form of conscious realization or decision
making. Attention is required for such protocols. No subjects have been noted to have
fine control over their P300.
5. The Role of Brain Fingerprinting in Criminal Proceedings
The application of Brain Fingerprinting testing in a criminal case involves four phases:
investigation, interview, scientific testing, and adjudication. Of these four phases, only the
third one is in the domain of science. The first phase is undertaken by a skilled investigator,
the second by an interviewer who may be an investigator or a scientist, the third by a
scientist, and the fourth by a judge and jury.
This is similar to the forensic application of other sciences. For example, if a person is
found dead of unknown causes, first there is an investigation to determine if there may have
been foul play. If there is a suspect involved, the suspect is interviewed to determine what
role, if any, he says he has had in the situation. If the investigation determines that the victim
may have been poisoned using ricin or cadmium, two rare and powerful poisons, then
scientific tests can be conducted to detect these specific substances in the body. Then the
evidence accumulated through the test, the investigation, and the interview are presented to a
judge and jury, who make the adjudication as to whether a particular suspect is guilty of a
In such a case, the science of forensic toxicology reveals only whether or not specific toxins
are in the body. It does not tell us when or where to look for toxins, or which toxins to look
for. We must rely on investigation to provide the necessary guidance on these issues. The
science of forensic toxicology also does not tell us whether a particular suspect is innocent or
guilty of a crime. The question of guilt or innocence is a legal one, not a scientific one, and
the adjudication is made by a judge and jury, and not by a scientist or a computer.
5.1.Phase 1: Investigation
The first phase in applying Brain Fingerprinting testing in a criminal case is an
investigation of the crime. Before a Brain Fingerprinting test can be applied, an
investigation must be undertaken to discover information that can be used in the test. The
science of Brain Fingerprinting accurately determines whether or not specific information
is stored in a specific person’s brain. It detects the presence or absence of specific
information in the brain. Before we can conduct this scientific test, we need to determine
what information to test for. This investigation precedes and informs the scientific phase
which constitutes the Brain Fingerprinting test itself.
The role of investigation is to find specific information that will be useful in a Brain
Fingerprinting test. As with any scientific test, if the outcome of the Brain Fingerprinting
test is to be useful evidence for a judge and jury to consider in reaching their verdict, then
the information tested must have a bearing on the perpetration of the crime. The job of
the investigator is to find features relevant to the crime that have the following attributes.
1. They are salient features that perpetrator almost certainly encountered in the course
of committing the crime (e.g., the murder weapon or the escape route).
2. The suspect has not been exposed to them in some other context, i.e., interrogation or
These features of the crime will be used in the Brain Fingerprinting test as probe stimuli.
If the suspect knows these specific features of the crime, and has had no access to this
information other than through committing the crime, then this will provide evidence of
his involvement in the crime. If the suspect lacks this knowledge, this will provide
evidence supporting his innocence. Brain Fingerprinting tests for the presence or absence
of this information stored in the suspect’s brain.
In some cases, the investigation will reveal no information about the crime that would be
known only to the perpetrator and to investigators. For example, in the case of a
disappearance, investigators may not even know if a crime has been committed, and if so,
what were the specific details of the crime. In some sexual assault cases, there may be
agreement between the alleged victim and the suspect as to all of the events that took
place, but disagreement as to the intent of the parties. Investigators may have made the
mistake of revealing to the suspect all that they know about a case. In such cases, no
probe stimuli can be developed that will provide evidence relevant to the discrimination
between a person who participated in the crime and one who did not, and no Brain
Fingerprinting test will be conducted.
The investigator must use his skill and judgment in discovering and evaluating
information to be used in the Brain Fingerprinting test, and any other evidence he
uncovers. There is always a degree of uncertainty in this process. If the investigator
finds a gun lying by the body of a person who apparently died of gunshot wounds, he
may conclude that it is the murder weapon. There is always a possibility, however, that it
is not. For example, perhaps the perpetrator shot the victim with one gun and planted
another gun to frame someone else. Ultimately, the evidence accumulated by the
investigator will need to be weighed by the judge and jury for its bearing on the guilt or
innocence of the suspect.
Criminal investigation is not science. Investigation does involve a high degree of skill
and expertise. The details uncovered by investigation are used as evidence in virtually
every trial. Expert testimony by investigators in criminal trials is very common. When
found to be relevant and based on reliable methodology, such evidence and testimony are
universally accepted as a viable part of the proceedings in court. This still does not mean,
however, that investigation is science. Unraveling the case and determining what is
significant and relevant will always depend on the skill of the investigator. Each case is
different, and there is an infinite variety of information that may be available to be
discovered. There are no standardized algorithms or procedures that will solve every
case. There will never be a time when we can simply feed all of the facts about a case
into a computer, and the computer will tell us what is significant or how the case is to be
solved. Although investigation is not science, investigation contributes substantially to
legal proceedings, and the evidence and expert testimony provided by investigators will
continue to be a valuable part of the process.
Some research scientists have expressed the view that if we just conduct enough research,
and define and study a nearly infinite panoply of parameters, someday the process of
investigation will become a scientific process that can be accomplished by applying a set
algorithm which does not depend on the skill and judgment of the investigator. There is
no reason to believe – or to hope – that this will ever happen. It is our view that science
will not, and should not, take the place of skilled criminal investigation. The infinite
variety of factors in a crime, and the intimate involvement of human beings in every
aspect of the crime, insure that the judgment and skill of the investigator will always be a
necessary ingredient in criminal investigations. Science will never make skilled
investigators obsolete, and should not attempt to do so.
The process of determining which items to use as probe stimuli will always depend on
the skill and judgment of the investigator, and will never be accomplished just by
applying some set scientific algorithm in the absence of human judgment. Ultimately,
the judge and jury will decide whether the evidence uncovered by the investigator and
embodied in the probe stimuli is convincing regarding the guilt or innocence of the
5.2.Phase 2: Interview of Subject
Once evidence has been accumulated through investigation, and before the Brain
Fingerprinting test is conducted to determine if the evidence can be linked to the suspect,
it can in some cases be very valuable to obtain the suspect’s account of the situation. For
example, if an investigation shows that specific fingerprints are found at the scene of a
murder, a suspect can be interviewed to determine if there may be some legitimate reason
that his prints are there. If the suspect’s story is that he was never at the scene of the
crime, then a match between his fingerprints and the fingerprints at that scene would be
highly incriminating. If, on the other hand, the suspect’s story is that he was at the scene
for some legitimate reason just before the crime, then fingerprints must be interpreted
differently, particularly if there is corroborating evidence of the suspect’s presence at the
scene before the crime.
The interview with the suspect may help to determine which scientific tests to conduct, or
how to conduct the tests. For example, a suspect may say that he entered and then left the
room where a murder was committed a short time before the murder, and that he never
saw or handled the murder weapon. In this context, a finding that the suspect’s
fingerprints matched the fingerprints on the doorknob would have little value, but a
finding that his fingerprints matched those on the murder weapon would provide
Prior to a Brain Fingerprinting test, an interview of the suspect is conducted. The suspect
is asked if he would have any legitimate reason for knowing any of the information that is
contained in the potential probe stimuli. This information is described without revealing
which stimuli are probes and which are irrelevants. For example, the suspect may be
asked, “The newspaper reports, which you no doubt have read, say that the victim was
struck with a blunt object. Do you have any way of knowing whether that murder
weapon was a baseball bat, a broom handle, or a blackjack?” If the suspect answers
“No,” then a test result indicating that his brain does indeed contain a record of which of
these is the murder weapon can provide evidence relevant to the case.
The suspect may have been exposed to information about the crime through an error on
the part of interrogators in previous interrogations, through familiarity with the scene or
the victim that has nothing to do with the crime, through hearsay from people directly or
indirectly involved, or through any number of other channels. It is vital that the suspect
be given a chance before the Brain Fingerprinting test to disclose any familiarity he may
have with the crime, so that any probes that he knows about for a legitimate reason can be
eliminated from the test. Recall that the probes contain crime-relevant information that
the suspect has no way of knowing except through having been present at the crime.
The targets are also discussed in the interview. Recall that the targets contain
information about the crime that the suspect knows whether he committed the crime or
not, and are used to establish a baseline brain response for information known to be
significant to this subject in the context of the crime. For example, if media reports
known to the suspect have disclosed the location of a murder (e.g., “behind Newton
Stadium”), then the location of the murder could be used as a target stimulus. In the
interview, the interviewer makes sure that the suspect does indeed know the information
contained in the target stimuli.
In the interview, the suspect is also given a list of all of the stimuli to be presented in the
test, without disclosing which stimuli are probes and which are irrelevants. The suspect
is asked to identify any stimuli that are significant to him for reasons that have nothing to
do with the crime. If any stimulus is significant to the suspect for reasons having nothing
to do with the crime, then that stimulus is eliminated from the test. For example, if the
suspect claims to know nothing about who committed the crime and to be unfamiliar with
any of the other people who are suspected of being involved, one of the probe stimuli
may be the name of a known accomplice. If that name also happens to be the name of the
suspect’s brother-in-law, then the stimulus would be significant to the suspect for reasons
unrelated to the crime, and this stimulus would be eliminated from the test. In this way,
the interview sets the stage for later interpretation of the test. If the suspect has just told
investigators that none of the stimuli are significant to him for any reason, and then the
probe stimuli are revealed through Brain Fingerprinting to be significant to the suspect in
the context of the crime, this scientific finding provides evidence relevant to the suspect’s
involvement in the crime.
A frequently asked question is, “What if one of the probe stimuli is significant to the
suspect for the wrong reason?” The interview serves to eliminate this potential confound,
as described above.
Things are significant to a person in context. The context of the probe stimuli in relation
to the crime is established in the interview, and prior to the Brain Fingerprinting test.
Immediately before each test, the context of the probe stimuli is established, and the
probe stimuli are described without being specifically named. For example, the subject is
told, “In this test, you will see several items, one of which is the murder weapon.” Then
several different stimuli are presented, including the murder weapon (e.g., “baseball bat”)
and several other options that would be equally plausible for an innocent person not
familiar with the crime (e.g., “broom handle”). We all have some familiarity with
baseball bats and broom handles, but in the context of the murder in which the baseball
bat was the murder weapon “baseball bat” will be significant for the perpetrator and not
for an innocent suspect who does not know what the murder weapon was.
In some cases, the interview will reveal that the suspect is already familiar with all of the
information that might be used to structure probe stimuli, for some reason unrelated to
committing the crime. For example, interrogators may have mistakenly revealed to the
suspect all that they know about the crime. In such a case, there is no remaining
information to be used to structure probe stimuli, and a Brain Fingerprinting test is not
conducted. If a Brain Fingerprinting test were conducted to test whether or not a suspect
knew details of a crime that had been told to him by investigators, the test would result in
an “information present” result, which would be correct. The probative value of such a
result with respect to committing the crime, however, would be nil. Such a test would
only reveal, correctly, that the suspect knows the information. Since the investigators
already know for certain that the suspect knows the information – because they told it to
him – this result would not provide any useful evidence with respect to solving the
crime. This is why a test is not conducted under such circumstances. Note that this is a
limitation only on when Brain Fingerprinting can be usefully applied, and not a limitation
on the scientific accuracy or validity of the technique. As with DNA, fingerprints, and
every other science, there are situations where a correct Brain Fingerprinting result is
simply not useful in solving a particular crime.
In short, Brain Fingerprinting determines scientifically and accurately what information
is stored in a person’s brain. It does not determine how that information got there. In
order for Brain Fingerprinting to be useful in identifying a perpetrator – that is, in order
for a correct “information present” Brain Fingerprinting result to be useful evidence
regarding a suspect’s participation in a crime – investigators must first discover
information that would be known to a perpetrator but not to an innocent suspect, and
ensure that the subject in question has not obtained that information through some means
other than participation in the crime. The interview contributes to this process.
Science is useful only when applied appropriately and intelligently. If the aim is solving
a crime or informing a judicial decision, then it is not useful to conduct scientific testing
in a vacuum, absent any consideration of what the results will mean in the context of the
crime. A test must be structured that will provide relevant and useful results. Also, once
the results have been obtained, they are useful only if they are interpreted in the light of
the other available evidence, as in the above example regarding fingerprints. Brain
Fingerprinting is like all other sciences in this regard.
The interview serves to refine the selection of stimuli so that the test results will provide
useful and relevant information, to establish the relevance of the stimuli, to eliminate
potential confounds in the scientific test, and to provide a background for interpretation
of the test results once they are obtained.
5.3.Phase 3: Scientific Testing with Brain Fingerprinting
It is in the Brain Fingerprinting test where science contributes to the process. Brain
Fingerprinting determines scientifically whether or not specific information is stored in a
specific person’s brain.
Brain Fingerprinting is a standardized scientific procedure. The input for this scientific
procedure is the probe stimuli, which are formulated on the basis of the investigation and
the interview. The output of this scientific procedure is a determination of “information
present” or “information absent” for those specific probe stimuli, along with a statistical
confidence for this determination. This determination is made according to a specific,
scientific algorithm, and does not depend on the subjective judgment of the scientist.
Brain Fingerprinting tells us the following, no more and no less: “These specific details
about this crime are (or are not) stored in this person’s brain.” On the basis of this and all
of the other available evidence, a judge and jury make a determination of guilty or
It has been proven in the scientific arena, and also in court, that the science of Brain
Fingerprinting has the following attributes:
1) This science is testable and has been tested;
2) This science has been peer reviewed and published;
3) This science is accurate, has an error rate extremely close to zero, and has standard
procedures for its application;
4) This science is well accepted in the relevant scientific community.
These facts have been discussed extensively elsewhere, and will not be further elaborated
here. In legal proceedings, the science of Brain Fingerprinting may play a central role,
but not an all-inclusive role. The Brain Fingerprinting test is preceded by an
investigation and followed by a legal determination, both of which fall outside the realm
Brain Fingerprinting determines scientifically what information is stored in a person’s
brain. It does not determine how that information got there. In order for a determination
that certain information is (or is not) stored in a suspect’s brain to be useful to a judge and
jury, the significance of this finding with regard to the crime must be established. This is
accomplished by the investigation and the interview, not by the Brain Fingerprinting test
itself. Brain Fingerprinting is similar to other sciences in this regard. For example, as
discussed above, a fingerprint test can determine that a suspect’s fingerprints match the
fingerprints found at the scene of the crime, but the fingerprint test does not tell us
whether that was because the suspect is guilty or because he was at the scene for a
legitimate reason before the crime.
Science can only provide scientific data – in the case of Brain Fingerprinting, a
determination of “information present” or “information absent” regarding specific details
of a crime in a specific brain. Science, no matter how accurate and valid, is only useful
in the context of an effective investigation. For example, the investigator must determine
whether or not there is some innocent, legitimate reason why a suspect’s fingerprints are
at the scene of the crime in order for the scientific finding of a fingerprint match to have
value in legal proceedings. In the absence of adequate investigation, science – no matter
how accurate and valid – may have little weight in the judicial process. Brain
Fingerprinting is no exception. The investigation and interview that precede the
scientific Brain Fingerprinting test are necessary to provide the information to test, and to
provide a background as to the significance of the test vis-à-vis the crime once the
scientific results are obtained. The weight of the Brain Fingerprinting evidence, and its
value to the judge and jury in making their determination, depend in part on the
effectiveness and skillful execution of the investigation that precedes the scientific
The science of Brain Fingerprinting does not tell us what information to test for. This is
determined according to the skill and judgment of the investigator – which is in the end
evaluated by the judge and jury.
Brain Fingerprinting does not test whether a person is guilty of a crime. This is
adjudicated by the judge and jury. The question of guilt or innocence is a legal
determination to be made by a judge and jury, not a scientific one to be made by a
scientist or a computer. What Brain Fingerprinting does is to provide evidence that can
be weighed by the judge and jury in making their determination of guilt or innocence.
5.4.Phase 4: Adjudication of Guilt or Innocence
The final step in the application of Brain Fingerprinting in legal proceedings is the
adjudication of guilt or innocence. This is entirely outside the realm of science. The
adjudication of guilt or innocence is the exclusive domain of the judge and jury. It is not
the domain of the investigator, or the scientist, or the computer. It is fundamental to our
legal system that decisions of guilt or innocence are made by human beings, juries of our
peers, on the basis of their human judgment and common sense. The question of guilt or
innocence is and will always remain a legal one, and not a scientific one. Science
provides evidence, but a judge and jury must weigh the evidence and decide the verdict.
5.5.The Role of Science in Legal Proceedings
In legal proceedings, the scope of the science of Brain Fingerprinting – and all other
sciences – is limited. The role of Brain Fingerprinting is to take the output of
investigations and interviews regarding what information is relevant, to make a scientific
determination regarding the presence or absence of that information in a specific brain,
and thus to provide the judge and jury with evidence to aid in their determination of guilt
or innocence of a suspect.
As with the other forensic sciences, the science of Brain Fingerprinting does not tell us
when to run a test, whom to test, or what to test for. This is determined by the
investigator according to his skill and judgment, and evaluated by the judge and jury.
Recall the case of the possible murder by poisoning discussed above. All the science of
forensic toxicology tells us is that there is or is not ricin or cadmium in specific cadaver.
Science does not tell us to look for these specific poisons in this specific case. This is
determined by the investigator according to his skill and judgment.
Similarly, the science of Brain Fingerprinting does not tell us what information to test
for. Again, this information is accumulated by the investigator according to his skill and
judgment. Brain Fingerprinting tells us scientifically whether or not this specific
information is stored in a specific person’s brain.
In the poisoning case mentioned above, science does not tell us whether a particular
suspect is guilty. This is determined by the judge and jury according to their human
judgment and common sense. The same is true of Brain Fingerprinting, and every other
Again, the science of Brain Fingerprinting does not tell us if a particular suspect is guilty
or not. Only a judge and jury can make a determination of guilt or innocence, and they
make this determination according to their human judgment, taking into account all of the
scientific and other evidence. It is our view that science, whether it be Brain
Fingerprinting or any other science, does not and should not seek to infringe the realm of
the judge and jury in making a determination of guilt or innocence.
Nor is science a substitute for skillful and effective investigation. Science depends on
investigation, which is outside the realm of science, to determine when to test, whom to
test, and what to test. The evidence provided by science and by investigation ultimately
must be weighed and evaluated by the human beings who are the judge and jury, on the
basis of their human judgment and common sense, in reaching their verdict regarding the
guilt or innocence of the accused.
It is fundamental to our legal system, and essential to the cause of justice, that the judge
and jury must be supplied with all of the available evidence to aid them in reaching their
verdict. Brain Fingerprinting provides solid scientific evidence that must be weighed
along with other available evidence by the judge and jury. In our view, it would be a
serious miscarriage of justice to deny a judge and jury the opportunity to hear and
evaluate the evidence provided by the science of Brain Fingerprinting, when available,
along with all of the other available evidence. In the case of a suspect presenting Brain
Fingerprinting evidence supporting a claim of innocence, such a denial would also be
unconscionable human rights violation.
Brain Fingerprinting is not a substitute for the careful deliberations of a judge and jury. It
can play a vital role in informing these deliberations, however, by providing accurate,
scientific evidence relevant to the issues at hand.
6. Current Uses and Applications
The various applications are as follows:-
1. Test for several forms of employment, especially in dealing with sensitive military
and foreign intelligence screening.
2. Individuals who were “information present” and “information absent”
3. A group of 17 FBI agents and 4 non-agents were exposed to stimuli.
4. To detect symptoms of Alzheimer's disease, Mental Depression and other forms of
dementia including neurological disorders.
5. Criminal cases.
6. Advertisements (researches are being carried on).
8. Security Testing.
The incidence of Alzheimer’s and other forms of dementia is growing rapidly
throughout the world. There is a critical need for a technology that enables early
diagnosis economically and that can also accurately measure the effectiveness of
treatments for these diseases. Research has now demonstrated that analysis of the P300
brainwave can show dementia onset and progression. MERMER technology, developed
and patented by Brain Fingerprinting Laboratories, includes the P300 brainwave and
extends it, providing a more sensitive measure than the P300 alone. Brain Fingerprinting
Laboratories is now developing diagnostic and monitoring systems for Alzheimer’s
using this exciting new technology.
With early diagnosis, the progression of Alzheimer's symptoms can often be delayed
through medications and dietary and lifestyle changes. Using the very precise
measurements of cognitive functioning available with this technology, pharmaceutical
companies will be able to determine more quickly the effects of their new medications
and potentially speed FDA approval. The non-invasive nature of P300/MERMER testing
technology and the simplicity of its administration will allow primary care physicians to
monitor the progress of their patients in their own offices and adjust treatments
accordingly. An accurate, inexpensive and easy to administer test for Alzheimer’s and
dementia will improve the healthcare process dramatically, and will also help to improve
the quality of life for millions of people.
“Information Absent” “Information Present”
How do we know what information people retain from a media campaign? There is a
new technology that allows us to measure scientifically if specific information, like a
product brand, is retained in a person’s memory. Brain Fingerprinting testing adds a
whole new dimension to the methods of measuring advertising effectiveness, going well
beyond subjective surveys and focus groups. The implications for the advertising
Industry are very exciting! Here are some of the possibilities:
1) What specific information do people retain from advertising?
Do they remember the product, the company, the retailer, the website, pricing and
promotional information, etc.?
2) What specific elements in an ad campaign have the most impact?
What do people pay attention to or respond to the most in an ad — what gets their
3) Which type of media is most effective?
If an advertising campaign uses TV, radio, magazine, web banners, billboards,
newspapers, email and direct mail, which of the media have the most effect on which
client base and how do those results vary with demographics?
4) What commercial is the most effective for a single product?
In an advertising campaign that uses multiple commercials or multiple printed
messages, which version is the most effective at reaching the target audience?
5) How effective is the product branding strategy?
Does a person or group of people remember the specific brand being advertised? If
so, how does its recognition compare with other brands? Which branding campaigns
are most effective for both new and established brands?
6) How effective is an ad campaign in different parts of the world?
If the same advertising campaign is run in various parts of the world, how does its
effectiveness vary from area to area? What specific aspects of the message are
retained by people in different countries? Do some areas respond differently to types
7) What is the correlation between the campaign and the point-of-sale?
How do the various campaigns and the types of media affect awareness at point-of-
sale. For example, which media is the most effective in raising awareness of a new
product with potential buyers in a superstore? How does this media type and
frequency vary in effectiveness with potential buyers on-line or with catalog users?
8) How do the effects of campaigns vary with the influence of time?
How does the specific information retained by an individual or group of people vary
over time? At what rate does the impact of an advertising campaign degrade or have
diminishing impact? For example, a specific advertising campaign may have a strong
impact short term, while another campaign causes the information to be retained over
a longer period of time. How do these results vary with multiple types of media,
product types and demographics?
Brain Finger-printing technology can play a significant role in Security Testing when
investigators know specific details of a crime, training or group affiliation. It can also
determine if a person has specific "classified" or confidential information stored in their
brain. Typical applications include:
1) Visa Applications
2) 2nd Level Testing
3) Polygraph "False-Positive"
4) 2nd Level Testing
5) Corporate Security
6) Insurance Fraud
7) Security Clearances
8) Computer Hacking
Brain Finger-printing technology can determine the presence or absence of specific
information, such as terrorist training and associations. This exciting new technology can
help address the following critical elements in the fight against terrorism:
1) Aid in determining who has participated in terrorist acts, directly or indirectly.
2) Aid 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.
3) Help to identify people who have knowledge or training in banking, finance or
communications and who are associated with terrorist teams and acts.
4) Help to determine if an individual is in a leadership role within a terrorist
One fundamental difference between a terrorist and an innocent suspect is that the
terrorist has detailed knowledge of terrorist activities and an innocent person does not. A
terrorist has committed a crime, received training in terrorism or worked with others in
planning terrorist attacks. The innocent suspect does not have this type of information
stored in his brain.
Brain Finger-printing technology is based on the principle that the brain is central to all
human acts. In a terrorist act, there may or may not be peripheral evidence such as
fingerprints or DNA, but the brain of the perpetrator is always there, planning,
executing, and recording the crime. The terrorist has knowledge of organizations,
training and plans that an innocent person does not have. Until the invention of Brain
Fingerprinting testing, there was no scientific way to detect this fundamental difference.
Brain Fingerprinting testing provides an accurate, economical and timely solution to the
central problem in the fight against terrorism. It is now possible to determine
scientifically whether or not a person has terrorist training and knowledge of terrorist
Brain Finger-printing testing can determine quickly and accurately whether or not
specific knowledge is present or absent in an individual. In a Brain Fingerprinting test,
words, pictures or sounds relevant to a crime, terrorist act or terrorist training are
presented by a computer, along with other irrelevant images and sounds. Electrical brain
responses are measured non-invasively through a patented headband equipped with
sensors. A computer then analyzes the brain responses and determines whether or not the
specific information is stored in the brain of the suspect. The results are not affected by
the willingness of the person being tested to tell the truth. By testing for specific
information, Brain Fingerprinting technology can accurately distinguish between a
trained terrorist and an innocent person who may have knowledge of certain locations,
people and events for legitimate reasons.
Brain Fingerprinting testing detects whether or not specific information is stored in a
person’s brain, not truth or falsehood. In fact, no questions are asked and no answers are
given during a Brain Fingerprinting test. Brain Fingerprinting testing cannot be used for
general, non-specific testing, something for which no reliable facts exist against which to
compare the subject’s answer. For example, a general question like “Are you a
terrorist?” is not something that can be addressed by Brain Fingerprinting technology.
However, the recognition of specific information from terrorist training or of individuals
at a training camp can be detected. Investigators must have reliable, factual details from
which to draw the information that will be used to structure the Brain Fingerprinting test.
Any known legitimate means through which a subject may have encountered crime or
terrorist-relevant information are examined prior to conducting a Brain Fingerprinting
test. Standard protocols ensure that the individual has a chance to reveal any
circumstances through which he may have had legitimate access to the crime-relevant
information in question. Any information the suspect has obtained through legitimate
means is eliminated from consideration before the test is administered. A suspect is
tested only on information that he has no legitimate means of knowing, information he
denies knowledge of, and for which he has no legitimate explanation if it turns out that
the information is indeed stored in his brain.
With the Brain Fingerprinting system, a significant scientific breakthrough has now
become a practical applied technology. A new era in security and intelligence gathering
has begun. Now, terrorists and those supporting terrorism can be identified quickly and
accurately. No longer should any terrorist be able to evade justice for lack of evidence.
And there is no reason why an innocent individual should be falsely imprisoned or
convicted of terrorist activity. A Brain Fingerprinting test can determine with an
extremely high degree of accuracy those who are involved with terrorist activity and
those who are not.
In advertising, Brain Fingerprinting Laboratories will offer significant advances in
measuring campaign and media effectiveness. Most advertising programs today are
evaluated subjectively using focus groups. We will be able to offer significantly more
advanced, scientific methods to help determine the effectiveness of campaigns and be
very cost competitive with current methodologies. This technology will be able to help
determine what information is actually retained in memory by individuals. For example,
in a branding campaign do people remember the brand, the product, etc. and how do the
results vary with demographics? We will also be able to measure the comparative
effectiveness of multiple media types.
In the insurance industry, Brain Fingerprinting Laboratories will be able to help reduce
the incidence of insurance fraud by determining if an individual has knowledge of
fraudulent or criminal acts. The same type of testing can help to determine if an
individual has specific knowledge related to computer crimes where there is typically no
witness or physical evidence.
7. Limitations of Brain Finger-Printing
The limitations of this technique are discussed with examples (in crime scenarios) as follows:
1) Brain fingerprinting detects information-processing brain responses that reveal what
information is stored in the subject’s brain. It does not detect how that information
got there. This fact has implications for how and when the technique can be applied.
In a case where a suspect claims not to have been at the crime scene and has no
legitimate reason for knowing the details of the crime and investigators have
information that has not been released to the public, brain fingerprinting can
determine objectively whether or not the subject possesses that information. In such a
case, brain fingerprinting could provide useful evidence. If, however, the suspect
knows everything that the investigators know about the crime for some legitimate
reason, then the test cannot be applied. There are several circumstances in which this
may be the case. If a suspect acknowledges being at the scene of the crime, but claims
to be a witness and not a perpetrator, then the fact that he knows details about the
crime would not be incriminating. There would be no reason to conduct a test,
because the resulting “information present” response would simply show that the
suspect knew the details about the crime – knowledge which he already admits and
which he gained at the crime scene whether he was a witness or a perpetrator.
2) Another case where brain fingerprinting is not applicable would be one wherein a
suspect and an alleged victim – say, of an alleged sexual assault – agree on the details
of what was said and done, but disagree on the intent of the parties. Brain
fingerprinting detects only information, and not intent. The fact that the suspect
knows the uncontested facts of the circumstance does not tell us which party’s
version of the intent is correct.
3) In a case where the suspect knows everything that the investigators know because he
has been exposed to all available information in a previous trial, there is no available
information with which to construct probe stimuli, so a test cannot be conducted.
Even in a case where the suspect knows many of the details about the crime,
however, it is sometimes possible to discover salient information that the perpetrator
must have encountered in the course of committing the crime, but the suspect claims
not to know and would not know if he were innocent. This was the case with Terry
Harrington. By examining reports, interviewing witnesses, and visiting the crime
scene and surrounding areas, Dr. Farwell was able to discover salient features of the
crime that Harrington had never been exposed to at his previous trials. The brain
fingerprinting test showed that the record in Harrington’s brain did not contain these
salient features of the crime, but only the details about the crime that he had learned
after the fact.
4) Obviously, in structuring a brain fingerprinting test, a scientist must avoid including
information that has been made public. Detecting that a suspect knows information he
obtained by reading a newspaper would not be of use in a criminal investigation, and
standard brain fingerprinting procedures eliminate all such information from the
structuring of a test. News accounts containing many of the details of a crime do not
interfere with the development of a brain fingerprinting test, however; they simply
limit the material that can be tested. Even in highly publicized cases, there are almost
always many details that are known to the investigators but not released to the public,
and these can be used as stimuli to test the subject for knowledge that he would have
no way to know except by committing the crime.
5) Another situation where brain fingerprinting is not applicable is one where the
authorities have no information about what crime may have taken place. For example,
an individual may disappear under circumstances where a specific suspect had a
strong motive to murder the individual. Without any evidence, authorities do not
know whether a murder took place, or the individual decided to take a trip and tell no
one, or some other criminal or non-criminal event happened. If there is no known
information on which a suspect could be tested, a brain fingerprinting test cannot be
6) Similarly, brain fingerprinting is not applicable for general screening, for example, in
general pre-employment or employee screening wherein any number of undesirable
activities or intentions may be relevant. If the investigators have no idea what crime
or undesirable act the individual may have committed, there is no way to structure
appropriate stimuli to detect the telltale knowledge that would result from committing
the crime. Brain fingerprinting can, however, be used for specific screening or
focused screening, when investigators have some idea what they are looking for. For
example, brain fingerprinting can be used to detect whether a person has knowledge
that would identify him as an FBI agent, an Al-Qaeda-trained terrorist, a member of a
criminal organization or terrorist cell, or a bomb maker.
7) Brain fingerprinting does not detect lies. It simply detects information. No questions
are asked or answered during a brain fingerprinting test. The subject neither lies nor
tells the truth during a brain fingerprinting test, and the outcome of the test is
unaffected by whether he has lied or told the truth at any other time. The outcome of
“information present” or “information absent” depends on whether the relevant
information is stored in the brain, and not on what the subject says about it.
8) Brain fingerprinting does not determine whether a suspect is guilty or innocent of a
crime. This is a legal determination to be made by a judge and jury, not a scientific
determination to be made by a computer or a scientist. Brain fingerprinting can
provide scientific evidence that the judge and jury can weigh along with the other
evidence in reaching their decisions regarding the crime. To remain within the realm
of scientific testimony, however, a brain fingerprinting expert witness must testify
only regarding the scientific test and information stored in the brain revealed by the
test, as Dr. Farwell did in the Harrington case. Like the testimony of other forensic
scientists, a brain fingerprinting scientist’s testimony does not include interpreting the
scientific evidence in terms of guilt or innocence. A DNA expert may testify that two
DNA samples match, one from the crime scene and one from the suspect, but he does
not conclude “this man is a murderer.” Similarly, a brain fingerprinting expert can
testify to the outcome of the test that the subject has specific information stored in his
brain about the crime (or not), but the interpretation of this evidence in terms of guilt
or innocence is solely up to the judge and jury.
9) Just as all witness testimony depends on the memory of the witness, brain
fingerprinting depends on the memory of the subject. Like all witness testimony,
brain fingerprinting results must be viewed in light of the limitations on human
memory and the factors affecting it (Harrington v. State, PBS 2004). Brain
fingerprinting can provide scientific evidence regarding what information is stored in
a subject’s brain. It does not determine what information should be, could be, or
would be stored in the subject’s brain if the subject were innocent or guilty. It only
measures what actually is stored in the brain. How this evidence is interpreted, and
what conclusions are drawn based on it, is outside the realm of the science and the
scientist. This is up to the judge and jury. It is up to the prosecutor and the defense
attorney to argue, and the judge and jury to decide, the significance and weight of the
brain fingerprinting evidence in making a determination of whether or not the subject
committed the crime.
10) Like all forensic science techniques, brain fingerprinting depends on the evidence-
gathering process which lies outside the realm of science to provide the evidence to
be scientifically tested. Before a brain fingerprinting test can be conducted, an
investigator must discover relevant information about the crime or investigated
situation. This investigative process, in which the investigator gathers the information
to be tested from the crime scene or other sources related to the crime, depends on the
skill and judgment of the investigator. This process is outside the scientific process; it
precedes the scientific process of brain fingerprinting. This investigative process
produces the probe stimuli to be tested. Brain fingerprinting science only determines
whether the information tested is stored in the brain of the subject or not. It does not
provide scientific data on the effectiveness of the investigation that produced the
information about the crime that was tested. In this regard, brain fingerprinting is
similar to other forensic sciences. A DNA test determines only whether two DNA
samples match, it does not determine whether the investigator did an effective job of
collecting DNA from the crime scene. Similarly, a brain fingerprinting test
determines only whether or not the information stored in the suspect's brain matches
the information contained in the probe stimuli. This is information that the
investigator provided to the scientist to test scientifically, based on the investigative
process that is outside the realm of science. In making their determination about the
crime and the suspect's possible role in it, the judge and jury must take into account
not only the scientific determination of "information present" or "information absent"
provided by the brain fingerprinting test; they must also make common-sense, human,
non-scientific judgments regarding the information gathered by the investigator and
to what degree knowledge or lack of knowledge of that information sheds light on the
suspect's possible role in the crime. Brain fingerprinting is not a substitute for
effective investigation on the part of the investigator or for common sense and good
judgment on the part of the judge and jury.
1) Farwell LA, Donchin E. The brain detector: P300 in the detection of deception.
Psychophysiology 1986; 24:434.
2) Farwell LA, Donchin E. The truth will out: interrogative polygraphy ("lie detection")
with event-related brain potentials. Psychophysiology 1991;28:531-541.
3) Farwell LA, inventor. Method and apparatus for multifaceted electroencephalographic
response analysis (MERA). US patent 5,363,858. 1994 Nov 15.
4) Farwell LA. Two new twists on the truth detector: brain-wave detection of occupational
information. Psychophysiology 1992;29(4A):S3.
5) Farwell LA, inventor. Method and apparatus for truth detection. US patent 5,406,956.
1995 Apr 18.
6) Picton TW. Handbook of electroencephalography and clinical neurophysiology: human
event-related potentials. Amsterdam: Elsevier, Vol. 3, 1988.