Picking Your Brain In The Name Of Security
While doing some in-depth research on biometric technologies recently,
I came across a subject I hadn't encountered before: brain fingerprinting.
At least I don't recall coming across it before -- perhaps a scan of my
brain would prove otherwise. The technology isn't a new concept, nor does
it rely on biometric traits, although it can best be used in tandem with
biometrics -- surprisingly -- to protect the privacy of those being tested.
Brain fingerprinting was invented more than 10 years ago, when the CIA
invested some money in a psychologist, Emanuel Donchin, and his student,
Lawrence Farwell. The theory was to find out what they could do to expand
on a standard EEG test, which uses super-sensitive electrodes to measure
fluctuations in electrical potential caused by patterns of brain activity.
Donchin specialized in a characteristic bump in the EEG scan called the
P300, which occurs approximately a third of a second after the subject
being tested recognizes something significant.
Farwell continued testing the viability of using P300 for criminal
cases, and ended up patenting the Farwell Brain Fingerprinting method. The
system basically works by flashing words or pictures relevant to a crime
on a computer screen, along with irrelevant words and pictures. Electrical
brain responses are measured through a patented headband equipped with
sensors. Farwell discovered that a memory and encoding related
multifaceted electroencephalographic response (MERMER) was elicited when
the brain processed noteworthy information it recognized. Therefore, if
details of a crime only a perpetrator would know about were presented, a
MERMER would be emitted by the brain of the perpetrator -- but not by the
brain of an innocent suspect.
In Farwell's Brain Fingerprinting, a computer analyzes brain responses
to detect the MERMER, and determines whether or not the crime-relevant
information is stored in the brain of the suspect. This is also known as
Computerized Knowledge Assessment. One of the strongest arguments for this
type of testing is that human judgment doesn't enter the picture -- the
results are scientific. Whereas other forms of questioning, like
interrogation, involve intimidation and verbal "persuasion," no
verbal communication is required with brain fingerprinting. And whereas
lie detector tests have been known to fail, especially among skilled liars
who have learned how to skew results by clenching their teeth, etc., the
impulses of the brain supposedly cannot be manipulated for the purposes of
Of course, there's a laundry list of reasons why this method is not
foolproof. The first that comes to mind is that the crime-relevant
questions and pictures are chosen by humans, and are therefore subjective.
What if an innocent subject is shown an image of the crime scene -- a
place he or she has been to before, but not necessarily at the time of the
crime? What if certain details of the crime match up with someone's
similar experiences, and therefore recognition is registered?
Farwell contends that his method has proven 100-percent accurate in
tests conducted on FBI agents, as well as in tests for a U.S. intelligence
agency and the U.S. Navy. It aided Missouri prosecutors in convicting a
serial killer in 1998, 14 years after the rape and murder of Julie Helton.
After J.B. Grinder underwent brain fingerprinting, in which he responded
positively to certain details of the crime, he confessed to Helton's
murder and was sentenced to life in prison. He subsequently confessed to
other murders of young women. Farwell also presented test results to a
court in Iowa in an attempt to exonerate a man that had been convicted of
a murder 22 years earlier, and who had claimed innocence. Farwell said the test
results showed, with 99.99 percent accuracy, that Terry Harrington had not
committed the crime. The test results prompted the only witness to the
crime to recant his testimony against Harrington in a sworn testimony,
admitting it was a fabrication. Yet the judge in the trial rejected the
new evidence in a 2001 ruling, claiming it was unlikely to change the
result of a trial. Harrington is appealing the ruling.
Farwell is a strong proponent of using brain fingerprinting to screen
airline passengers, and as an added security measure at various screening
checkpoints. The theory is that people could be screened without revealing
their names, through the use of biometrics. For instance, at the same time
the brain wave test was given, biometric data like fingerprint or iris
scan would be gathered to link the person being tested to their physical
profile. The biometric profile would only need to be updated once every
few years. The person being tested would then put on a headset and watch
video images on a standard computer monitor for 10 minutes. The test would
be used to present data and information terrorists are familiar with.
Since the brain fingerprinting would be completely automated, it would
not be subject to human interpretation, and therefore would be unbiased to
race, creed, color, sex, religion, and other individual characteristics.
The computerized security risk factor profile generated by the brain
fingerprinting would be linked to a person's biometric data, but not necessarily to the person's name.
The very idea of brain fingerprinting conjures up images of a Big
Brother-like world in which knowing too much could be dangerous, and the
wrong response to an image could get you convicted of a crime you may or
may not have committed. Then again, if the technology is used correctly
and unobtrusively, perhaps it could be beneficial for screening out
terrorists or other threatening characters.
The one major flaw I see in
it, however, is the contention that it is 100 percent automated, and
therefore scientifically sound. The very nature of the questioning that
fuels the MERMER is subjective. Just as the very nature of the information
collected from a crime scene is fueled by human input. Of course, there
are standards and procedures for collecting such information, just as I'm
sure there will be standards for questioning and video presentation if
brain fingerprinting is ever widely implemented by law enforcement. I just
hope those adopting this technology proceed with caution, as there is
obviously a huge potential for abuse and error.
Laura Guevin is the editorial director of BiometriTech,
an online magazine and newsletter covering biometric technologies and
products. She welcomes your comments at firstname.lastname@example.org.