Creativity and mental illness have long been linked in the popular imagination and there is also research evidence to suggest that creative people have a higher likelihood of mental illness in their family and a slightly-raised risk of bipolar disorder and schizophrenia. Researchers from the Karolinska Institute in Stockholm used brain scans to compare people who did well on creative, puzzle-solving problems and people suffering from schizophrenia. They found that both groups had a reduced number of dopamine receptors in a part of the brain called the thalamus. The thalamus acts as a kind of filter for information before it moves on to the cortex region which handles understanding and reasoning. So, in effect, this filter could be weaker in people with higher creativity and/or schizophrenia allowing the former to combine ideas and concepts together in new and original ways and leading the latter to develop bizarre, unusual and sometimes harmful ways of looking at the world.
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