Scientists decode contents of dreams From the dream accounts they picked out 20 of the most commonly occurring themes, such as "car," "man," "woman" and "computer," and gathered pictures which represented each category. The participants were then asked to view the images while their brains were scanned a second time. By comparing the second set of brain activity data with the recordings made just before the volunteers had been woken up, the researchers were able to identify distinctive patterns in three key brain regions which help us process what our eyes see. They also found that activity in a number of other brain regions with more specialised roles in visual processing, for example in helping us recognise objects, varied depending on the content of the dreams. Finally, they built a computer model which could predict whether or not each of the selected themes was present in the participants' dreams. Yukiyasu Kamitani of the ATR Computational Neuroscience Laboratories in Kyoto, who led the study, told Nature News: "By analysing the brain activity during the nine seconds before we woke the subjects, we could predict whether a man is in the dream or not, for instance, with an accuracy of 75 to 80 per cent." 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. Dr Katamani added: "Our study shows that during dreaming, some brain areas show activity patterns similar to those elicited by pictures of related contents. Thus, using a database of picture-elicited brain activity and a pattern recognition algorithm, we can read out, or decode, what a person might be seeing from brain scans during dreaming. In this study we were able to decode only basic object category information, but the method could be extended to decode more dynamic and emotional aspects of dreams.