Thursday
13 January 2005
19:00 - 20:30
How would you feel about having your mind read by a machine? Is this the ultimate invasion of privacy? Find out more about the sophisticated memory-testing technologies currently being used on criminals in the USA and discuss whether we should use them here.
Review: The truth, the whole truth, and nothing but the truth
by Jane Qiu
Machines that can read your brain and detect if you are telling the truth are now science fact, rather than science fiction. But how accurate is the technology? Can we really trust the 'mind-readers' to convict or exonerate suspects? Naked Science asked the experts and audience in an event called 'Criminal Memories' at the Science Museum's Dana Centre.
The pattern of brain activity is different when a person is making up lies instead of retrieving genuine memories, explained Dr Paul Matthews of University of Oxford. And determining these 'brain fingerprints' is the key to the new generation of lie detectors.
Investigators can now use two technologies for brain analysis: electroencephalography (EEG), which measures the electrical activity of the brain, or functional magnetic resonance imaging (fMRI), which can map out the parts of the brain that are involved during particular tasks such as lying.
The question is, how clear cut are the results? 'The technology can determine only in terms of probability and likelihood [whether someone is telling the truth],' cautioned Dr Matthews.
Tor Butler-Cole, a medical ethicist at King's College London, was also wary of the issue of uncertainty.
'The mistake rate for DNA fingerprinting is one in one billion; whereas for brain fingerprinting, it is one in a couple of hundreds. So there is a huge difference,' said Butler-Cole.
'But the criminal justice system is already using a very inaccurate source of evidence the eyewitness. Any additional information should be used as the legal system is imperfect anyway,' responded a member of the audience.
EEG-based technology has already been used to provide forensic evidence in an American criminal court. Dr Jennifer Vendemia of the United States' Department of Defense Polygraph Institute is currently investigating the science of deception and brain activity.
'I am terrified [that people are so enthusiastic about it],' said Dr Vendemia. 'Great caution must be taken. Rushing the technology from laboratories into the real world would be the most dangerous thing to do,' she remarked.
Should we use brain fingerprinting or similar technologies as a means of providing evidence in criminal courts in UK? This question was posed to the audience at the end of the debate. The electronic voting system showed that 23 per cent said 'yes', 55 per cent said 'no' and 20 per cent didn't know.