
15 March 2004
News Feature
Infallible
witness
CIA
double agent Aldrich Ames managed to pass polygraph tests, designed
to find traitors, even as he was selling out other US agents to the Soviet
Union. Polygraphs — conventional lie detector tests — are based on emotional
responses to stress such as increased heartbeat and blood pressure, and
excessive sweating. Responses that can be faked.
But whatever the outward response, the
brain will always answer honestly. Discovering this answer from involuntary
brain activity is where brain fingerprinting (BF) comes in. BF taps into the
specific information stored in a person’s memory, providing a scientific
solution to the problem of identifying criminals and trained terrorists. This
scientific determination of guilt or innocence has been ruled admissible in US
court, meaning this new branch of forensic science has the potential to
revolutionize the whole justice system. Indeed, the revolution has already
started.
In February 2004,
a Brain Fingerprinting test showed that
Jimmy Ray Slaughter's brain did not contain
a record of salient features of the crime of which he had been convicted.. He is
on death row in Oklahoma for the murder of his girlfriend Melody Wuertz and their daughter Jessica. Slaughter’s fate is not yet known. But, the
implications of the technology will reach much further than the criminal world.
BF creators Brain Fingerprinting Laboratories, based in Seattle, say the
same technology will be used to speed to market drugs for brain disorders
including Alzheimer’s disease (AD) and Hutchinson’s, help identify fraud, and
strengthen security in areas such as visa applications and protection of
classified information.

Farwell measures
brain-wave responses of a person looking at words or pictures displayed on a
computer screen using a headband with built-in electrodes
The Gazette/Buzz Orr
Brain waves
The most detailed
knowledge of any crime is locked away in the brain of the person who committed
it. BF provides a method by which these invisible clues can be tapped to
determine, with scientific certainty, whether the story a suspect is telling
matches what is stored in his or her brain.
BF test results
suggest that Slaughter’s story and the information in his brain match. His claim
to have no knowledge of the murder scene was proven to be true, enough to
question the validity of the guilty verdict and have him granted a stay of
execution. The same technology could soon be available to establish the guilt or
innocence of suspects at a much earlier stage.
‘I envision that
over the next 10–20 years police officers and investigators throughout the world
will be trained as part of their regular law-enforcement education to record the
elements of a crime scene for use in BF tests,’ says Drew Richardson, a former
US Federal Bureau of Investigation (FBI) agent and scientist, who joined Brain
Fingerprinting Laboratories. ‘Up to 70% of major crimes would be appropriate
someday for BF technology,’ he says. Conventional fingerprinting and DNA is only
available in 1% of cases. Brain Fingerprinting Laboratories hold three patents
for BF testing in the forensic area.
‘Ah-ha’
The technique is not for
interrogation. It does not require any questions or any answers. It reveals
objectively whether information is present in the brain, regardless of whether
any false or truthful statements are made by the subject. The brain does the
talking.
Hidden
information is uncovered by measuring brain-wave activity in response to
crime-related pictures or words. Changes in brain waves allow a determination of
‘information present’ or ‘information absent’ regarding specific details of a
crime in a specific brain. ‘We cannot download the contents of the brain,’ says
BF inventor Laurence Farwell of Brain Fingerprinting Laboratories. ‘But what we
can do is determine whether the suspect recognizes details significant in the
context of a crime.’
Presented with details of the
crime, the guilty person cannot help but elicit an involuntary, but detectable
spark of recognition in the brain. This response is automatic, so there is no
way to suppress or fool the system. ‘If an elephant were to walk into the room,
you may not respond overtly, but your brain cannot help but recognize that it is
an elephant. There is always the “ah-ha” response in the brain,’ says Farwell.
Find the MERMER and you have found the murderer
The ‘ah-ha’ response is
characterized by specific, measurable brain response known as a MERMER. A MERMER
will only be emitted by the brain of the perpetrator, with details of the crime
in his brain, and not by an innocent suspect who does not have this record in
his brain. Find the MERMER and you have found the murderer.
MERMER
A MERMER is a part of the
brainwave observed in response to familiar information. When the brain
recognizes something, the memory centres are stimulated. The neurons fire
synchronously, eliciting characteristic changes in brain activity. It is these
changes, which can be measured using electrodes, that investigators look for
when trying to determine whether someone recognizes a particular piece of
information.
When subjected to
a rare, but meaningful stimulus, increased neuron activity results in an
increase in voltage, typically within 300–1000msec after the stimulus, called a
P300. This is called an event-related potential (see Box, above). For example,
if a subject is exposed to a series of random names and occasionally one of
those names is the subject’s name, a P300 response is evoked.1,2
The utility of the P300 in detection of
deception was recognized as early as 1988, when it was shown that it could be
used to identify college students concealing guilty knowledge of having stolen
something.3
However, the P300 has only a 87.5% success rate
in revealing the presence of relevant information.
Farwell’s test is
based on the discovery that the P300 is only a subcomponent of a more
complicated response called a MERMER, which is elicited when a person recognizes
and processes a stimulus that is particularly noteworthy to him/her.4
The MERMER, memory and encoding related
multifaceted electroencephalographic response, includes the P300 and another
longer latency, electrically negative subcomponent with a latency of up to two
seconds post-stimulus. In other words, a positive wave followed by a negative
one. Tests using the MERMER produced no false negatives or positives and no
indeterminates.4
When details of a crime are known to the suspect, a MERMER will be
detected. A MERMER will not occur in an innocent subject.
However, there is
one major drawback. Although it is possible to determine whether information is
present in the brain, it is not possible to say why it is there. This is why
investigators have to find information that only the guilty person will have.
This means eliminating any details that may have come out during the trial, for
example, to which an innocent person may have been inadvertently exposed.
Event-related potentials
There are about a billion neurons in the brain that
communicate with each other using electrochemical signals. The ongoing changes
in these signals, which are measured using scalp electrodes, are recorded as
continuous changes in voltage over time, called the electroencephalogram (EEG).
Buried in the EEG are signals that reveal information about brain processes.
These signals are detected by timing changes in the EEG with the onset of events
such as listening to a sound or viewing a picture. The resulting activity is
called an event related potential (ERP), which is distinguishable from
background brain activity. The ERP can be broken down into several basic
components represented as positive or negative fluctuations in the ERP waveform.
Components that occur prior to 100ms are thought to reflect information
processing in the early sensory pathway, for example the auditory neural ERP
stems from neuronal impulse traveling from the cochlea through the auditory
brain centres. Longer latency ERP components include P1, P2, N1, N2, N400 and
P300 components. These are named by the polarity (P for positive) and either
their ordinal position (P1 is the first positive wave) or their latency after
onset of stimulus (N400 is a negative fluctuation peaking at 400msec from onset
of stimulus). Generally the components occurring before 250msec are thought to
reflect late sensory and early pre-conceptual processes, whereas those after
250msec are thought to reflect higher level cognitive processes such as memory
or language.
‘Brain fingerprinting could have significant
commercial potential within market segments of interest to Lilly,’ Christian
Fibiger, Lilly Research Laboratories
100% accurate
Initial lab testing of BF
technology was funded by the US Central Intelligence Agency (CIA) and the FBI.
One of the first studies involved testing which people in a group were FBI
agents, by looking for a MERMER in response to words and phrases that only FBI
agents would recognize. A headband with sensors is placed on the subject’s head
and a series of words and pictures, some of which are relevant and some are not,
are flashed on a computer screen (see Box, below). The brain waves produced in
response are recorded and analyzed to determine whether there is an involuntary
spark of recognition to any of this information. The FBI agents were identified
with 100% accuracy. Similar tests with US navy doctors were equally successful.
BF was also used to identify who, of four volunteer test subjects, was
responsible for the theft of anhydrous ammonia (used to make methamphetamine)
from a farm in Fairfield, Iowa. Each subject was exposed to information relevant
to the crime to determine which one of them exhibited the ‘ah-ha’ response. The
guilty party, who had already confessed and done jail time, was identified.
Real crime
Rigorously conducted lab
tests are one thing, but looking into the mind of a real killer is a different
story. Farwell had the opportunity to do this when sheriff Robert Dawson called
on Brain Fingerprinting Laboratories to test JB Grinder who, for 15 years, had
been the chief suspect in the vicious murder of a young girl in Missouri. To
identify the murderer, the investigators had to uncover information that only
the real murderer would have, and establish that Grinder could not have that in-
formation for the wrong reasons
(for example, because somebody told him or he had seen the crime
scene innocently). Tests showed that the record stored in Grinder’s brain
matched the crime scene. Faced with certain conviction and a probable death
sentence, Grinder pled guilty in exchange for life without parole and confessed
to three previously unsolved murders of young women. BF was also used to
exonerate a man who said he was wrongly convicted of murder. Terry Harrington (a
black man) was found guilty of murdering a (white) security guard in Iowa in
1978. BF tests on Harrington revealed that the information in his brain did not
match the crime scene (see Figure 1). The brain response to the probes (blue
line) is the same as the response to the irrelevants (green line). Harrington’s
brain response to his alibi show the information stored in his brain matches his
alibi (see Figure 2). The judge ruled that the BF test results ‘meet the legal
standards for admissibility in court for scientific evidence,’ and the murder
conviction was reversed in 2003. In the Slaughter case, BF testing proved that
the suspect had no knowledge of the baby’s bullet wounds, where the woman was
killed or details of the stab wounds inflicted. Preliminary analysis suggests
that there is a 99% chance that his brain record does not match what he is
convicted to death row for having committed, says Farwell. All Slaughter’s
appeals had run out, but Slaughter's attorneys claim that the BF test results
are sufficiently
scientifically rigorous to warrant a stay of execution.
Harrington’s get out of jail card

Figure 1
Figure 2
Figure1:
Terry Harrington’s brain responses to the details of the crime scene. The
response produced by the probes, information relevant to the crime, produces
the same response as irrelevant information (green line). Target information,
information he knows, produces a MERMER (red line). This suggests that
Harrington's brain does not contain information relevant to the crime for
which he was convicted.
Figure 2:
Terry Harrington's responses to information about his alibi. The probes,
information about his alibi, produce a MERMER. Target information (red line),
information we know he knows, also produces a MERMER. This suggests that the
record stored in Harrington's matches his alibi.
Multiple-choice test for the brain
Three kinds of information are used to determine whether a subject
has specific crime-related information in his brain:
• Targets: information the subject definitely knows; this can be
ensured by telling the subject before the test starts.
• Irrelevants: information that subject definitely does not know;
this can be ensured by simply making up the information.
• Probes: information relevant to the crime or situation, which the
subject may or may not know.
The response of the brain to information is measured using a
headband with electrodes. Target information elicits a ‘yes’ response or a
MERMER. This is used as a control. Irrelevant information will not elicit a
MERMER. A MERMER in response to probe stimulus indicates recognition or the
presence of certain information.
Alzheimer’s
MERMER testing will also be used by pharmaceuticals companies to
speed to market new drugs for brain disorders such as AD. Brain Fingerprinting
Laboratories has already had discussions about a possible collaborative venture
with drug giant Eli Lilly.
‘Clearly there
exists in AD and other cognitive disorders a need for both improved
drug-efficacy testing protocols and accurate treatment monitoring,’ says
Christian Fibiger, vice president of neuroscience discovery research and
clinical application at Lilly Research Laboratories in Indiana. ‘[BF] could have
significant commercial potential within market segments of interest to Lilly,’
he says.
Brain Fingerprinting Laboratories
has already patented a technology that for the first time can measure how memory
and cognitive functioning of AD patients are affected by medications on a
short-term basis. And even the rudimentary first-generation test protocol has
been shown to detect AD as accurately as magnetic resonance imaging, positron
emission tomography and routinely used subjective testing. The new test only
takes 30 minutes and is based on a personal computer. Similar test protocols
usable with the same equipment for other neurological disorders, such as Hutchinson’s
disease, are also being developed.
This technology
will speed up development and US Food and Drug Administration approval of new
drugs by improving testing at clinical trials, aiding in the early diagnosis of
AD, and providing physicians with a tool to determine the short and long-term
effects of a particular drug.
This technology
is expected to have particular application in the development of a class of
drugs called gamma secretase inhibitors. These drugs reduce the accumulation and
deposition of beta-amyloid plagues, insoluble protein structures that cause
memory problems when they accumulate in the brain. MERMER testing can be used to
evaluate the efficacy of the drug in slowing the progression of memory loss
caused by amyloid plagues. Currently, there are 19 drugs under development to
slow the progression of AD or prevent it.
In AD testing,
technicians present words, phrases and images that are both known and unknown to
the patient. The brain responds, and the technician can use this response to
measure deterioration of memory and also deterioration of the speed, accuracy
and efficiency of the cognitive processes. The number of tests for individual
patients would range between four and 12/year. The results would also be used by
physicians in a clinical setting to evaluate the medications already being
prescribed, to decide whether they should be changed. A commercial testing
product is expected to be available within 18–24 months.
With the average
age of the population increasing, the number of people with AD is expected to
increase nearly 300% by 2050. The US market alone has the potential for AD
systems and services in excess of $2bn/year. The market for BF equipment is
estimated to be 60,000 units at a cost of between $15,000 and $25,000.
Another potential
application of the technology is identifying trained terrorists before they
strike, including those in long-term ‘sleeper’ cells. BF technology can be used
to detect records in the brain of crimes in the planning or association with
terrorist groups. Tests will use information that only terrorists or gang
members would have access to. This might include details of training camps or
locations specific to a particular group or gang. The results of the tests will
likely be used to make decisions over who can be safely issued a visa or given
leave to enter a foreign country.
References
1 Donchin et al,
Behavioural Brain Sciences 1988, 11, 357
2 R Jr Johnson,
Advances in psychophysiology 1988, 2, 69
3 Rosenfeld et al,
International Journal of Neuroscience 1988, 24, 157
4 Farwell et al,
Journal of Forensic Sciences 2001, 46, 1
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Copyright 2004 Society of Chemical Industry - all rights reserved.
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