Researchers from the Max Planck Institute for Psycholinguistics in Nijmegen and from the universities of Amsterdam and Utrecht (all in the Netherlands) have been looking into the links between neuroscience and the way in which people's beliefs, and the process of reading, interact. In their experiment two groups of participants with very different belief systems read out statements such as "I find euthanasia an acceptable..." before stating whether they agreed or disagreed with it. As they read out the sentences their brains' responses were measured by EEG (electroencephalography). Even before they reached the part where they had to say whether they agreed with the sentence or not sentences that the participants strongly disagreed with produced two characteristic brain waves. The first, known as the LPP (late positive potential) effect signifies an emotional response and the second, known as the N400 effect is a well-known brain response to an unlikely or impossible meaning e.g. 'I carried the aircraft carrier.' No such brain waves were observed in people who agreed with the statement they were reading out. The responses to the statements were much quicker than the researchers were expecting, occuring within a fifth of a second.
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