Kai-Ching Yu said: 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.
The study was published in the journal Dreaming.