A team of world-leading neuroscientists has developed a powerful technique that allows them to look deep inside a person's brain and read their intentions before they act. They have devised a system that analyses brain activity to work out a person's intentions before they have acted on them. The research breaks controversial new ground in scientists' ability to probe people's minds and eavesdrop on their thoughts, and raises serious ethical issues over how brain-reading technology may be used in the future. The research builds on a series of recent studies in which brain imaging has been used to identify tell-tale activity linked to lying, violent behaviour and racial prejudice. The computer learns unique patterns of brain activity or signatures that correspond to different thoughts. It then scans the brain to look for these signatures and predicts what the person is thinking. More advanced versions may be able to read complex thoughts and even pick them up before the person is conscious of them. Barbara Sahakian, a professor of neuro-psychology at Cambridge University, said the rapid advances in neuroscience had forced scientists in the field to set up their own neuroethics society late last year to consider the ramifications of their research.