Now science tells us how we really feel Scans of 'emotion engine' spot if we mean what we say
Scanners that could determine our political beliefs, pinpoint our involvements in crime, or even uncover extra-marital liaisons are being developed by neurologists.
It sounds like science fiction, but the idea is being taken seriously by neurologists following breakthroughs in research on the amygdala, an almond-shaped region of the forebrain.
During one trial, scientists read the electrical patterns of amygdalas in individuals undergoing cognitive trials and decoded volunteers' emotions from their scanners.
'The whole field has become immensely exciting,' said Dr Stephen Lawrie of Edinburgh University's psychiatry department. 'It has immense potential, not just for understanding how we think and feel, but for helping people with severe emotional problems, including those with schizophrenia.'
The amygdala is the mind's emotional engine and research into its operation has become one of the hottest topics in brain science. This month, neuroscientists and psychologists meet in Galveston, Texas to debate developments at a three-day international conference, the first dedicated to amygdala research.
Most research on brain activity has, until recently, focused on thinking patterns and ignored the far more tricky issue of how we express and feel emotion.
'We don't know why we feel emotions and what good they are,' said Dr Rashid Shaikh of the New York Academy of Sciences, which is organising the conference. 'Now we have the means to begin to get an answer.'
Research on rat brains in the 1980s revealed that the amygdala controls the expression of fear and anxiety. Scientists then turned to the human brain to determine if ours worked in a similar manner, armed with newly developed magnetic resonance scanners that measure brain activity by analysing changes in oxygenated blood flow.
The most remarkable studies were by Yale and New York University researchers, led by Dr Elizabeth Phelps. Volunteers were shown pictures of black and white people. White participants were checked in advance to make sure that none expressed overt anti-black feelings.
But when these individuals were presented with pictures of black people, images of some them revealed intense amygdala activation - a sure sign they were feeling fearful or anxious. Pen-and-paper psychological tests designed to reveal innate racism uncovered some participants who suppressed anti-black feelings - the same individuals whose amygdalas were most active during tests. They claimed not to be racist, but their brains gave the game away .
Such research raises the prospect that attitudes and feelings we try to conceal will one day be uncovered by researchers. Lying politicians, spin doctors and cheating sportsmen (and husbands) will suddenly find life uncomfortable.
Such prospects are relatively distant. In the shorter term, amygdala research offers scientists a chance to transform the treatment of psychiatric conditions.
'In schizophrenics, and in those who are at risk of developing the condition, we find amygdalas that are much smaller than those in most individuals,' Lawrie said. 'In other words, the emotional barometers they use to measure the outside world are damaged. They may feel anxious or fearful about innocent objects or passers-by, which can trigger all sorts of paranoid responses.
'We can now think about how to develop drugs that could alleviate the problem, or design cognitive therapies to improve their condition.'
Robin McKie | 
