Recording dreams

Have you ever had an absolutely fantastic dream, woken up and promptly forgotten everything that happened in it? I certainly have, and would love to be able to watch some of the more interesting ones back later. The idea of reading and recording dreams has been the preserve of science fiction, but as our understanding of the brain improves, it is getting closer to reality.

A group of researchers in Japan, led by Yukiyasu Kamitani, have previously used functional magnetic resonance imaging (fMRI) to identify which image a subject is looking at. Last week, they presented an extension of this work, where they looked at the dreaming brain.

fMRI was used to record the brain activity of three volunteers whilst they slept. When the researchers detected brain waves associated with dreaming, they woke the volunteer and asked them what they had dreamt of. In this way, they were able to collect data on which parts of the brain are active when dreaming of a number of different objects. The volunteers were then shown images of these objects whilst awake and their brain activity recorded. By comparing the data gathered whilst awake with that from the dreaming brain, the volunteers were able to predict the content of the dreams. For example, they could predict whether or not a man was present in a dream with an accuracy of 75-80%.

At the moment, the method is limited to a few common objects, such as ‘man’, ‘woman’ and ‘computer, but with more data the number of objects that can be identified could increase.

Interestingly, areas involved in visual processing and object identification in the group’s earlier work were also found to be active whilst dreaming, implying dreams are interpreted by the brain in a similar way to images from the eyes.

While we may still be some way off recording our dreams, this work is certainly a step in the right direction and could help to understand why we dream and how dreaming is related to brain activity.