Your eyelids get heavy and before you know it you’re caught up in a dream where you find yourself sitting naked next to a unicorn in high school algebra class. We all dream and while our dreams can pull things from our own reality as well as seemingly unrelated strangeness, how we dream is mostly a science mystery.
Deciphering exactly where the brain creates the blueprint for a dream is what a group of French scientists set out to do. The team conducted an experiment with people who suffer from auto-activation deficit syndrome (more on that in a moment) and came to the conclusion that at its most basic, dreams are generated by the brainstem. This is the part of the brain that connects to the spinal cord and helps regulate our sleep–a “bottom-up” process rather than a result of the brain’s higher functions.
For the study the scientists looked at two groups: people who reported frequent dreaming habits and those who were auto-activation deficit. People who suffer from auto-activation deficiency lose the ability to spontaneously activate any cognitive or emotional processes. They seemingly have nothing at all going on upstairs and often sit quietly in the same place all day without speaking or moving. They can answer questions and recall memories, but left to their own thoughts, their mind is a ghost town.
The two groups of 13 people each were asked to keep dream diaries and members of both test groups reported dreaming. Not all subjects in the auto-activation deficit group reported dreaming and those who did had far less bizarre dreams than those in the control group.
While the people who lacked the ability to have spontaneous thoughts while awake, they were still able dream at night. This suggest that at its core, dreaming is like a reflex. The fact that their dreams of just walking or sitting appear simple compared to the vivid complex dreams of the control group suggest that higher-order processes are required to create the strange scenarios most people find in their dreams.
Via L.A. Times