They are our some of our most private and also easily forgotten experiences, but scientists have now worked out how to tell what we are dreaming about.
The Japanese researchers managed to decode the dreams of a group of volunteers and pinpointed when they were dreaming about such things as cars and women.
They scanned the brains of three male volunteers as they slept to monitor changes in activity which could be related to the content of their dreams.
Speaking at the Society for Neuroscience annual conference last week, the scientists said their findings indicate that patterns of activity in certain visual areas of the brain are the same whether we are awake or dreaming.
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