A study published in the journal Dreaming has revealed that your body position during sleep can greatly influence the content of your dreams. Calvin Kai-Ching Yu, a researcher at Shue Yan University in Hong Kong spoke to 670 students, getting them to fill out detailed surveys about their sleep and dream lives.
He found that those who slept on their stomachs reported a higher incidence of feeling sensations related to ‘sex’ and ‘persecution’ than those who adopted other sleeping positions.
The researchers think it might have something to do with the brain getting less oxygen, which results in the sensation of feeling constricted. They also speculated that when we sleep face down, our genitals receive more stimulus from the bed and sheets, so our brains incorporate that into dreams with an erotic theme.
Kai-Ching Yu concluded that
“This study provides the evidence that dream experiences, and in particular dream content, can be influenced by body posture during sleep. I believe that the brain during sleep is not at all totally detached from the external world, and stimuli, including those stemming from the environment, are probably incorporated into dream content more often than people observe or are aware of. The unconscious brains of the dreamers try to make sense, and even make use of, the external stimuli.”