Researchers looked at why some people recall their dreams every morning while others claim to never remember them.
The researchers looked at the brain activity in the two types of dreamers in hopes of finding what causes the distinction, a French National Institute of Health and Medical Research (INSERM) news release reported.
The noticed more activity in the temporo-parietal junction (the "information-processing hub" of the brain) in people who tended to remember their dreams.
"Increased activity in this brain region might facilitate attention orienting toward external stimuli and promote intrasleep wakefulness, thereby facilitating the encoding of dreams in memory," the news release reported.
They found "high dream recallers" wake up twice as often as "low dream recallers" during the night and their brains are more reactive to auditory stimuli. These increased responses could be what triggers they higher rate of wakefulness, which would allow the individual to memorize their dreams periodically throughout the night.
The researchers used Positron Emission Tomography (PET) to measure the brain activity of 41 volunteers. The study participants were divided into two groups; the "high dream recallers" who remembered their dreams 5.2 mornings of the week and "low dream recallers" how only remembered them about twice a month.
The high dream recallers had a higher spontaneous activity rate in both their medial prefrontal cortex (mPFC) and in the temporo-parietal junction (TPJ), which is responsible for "attention orienting toward external stimuli," the news release reported.
"High dream recallers are more reactive to environmental stimuli, awaken more during sleep, and thus better encode dreams in memory than low dream recallers. Indeed the sleeping brain is not capable of memorising new information; it needs to awaken to be able to do that," Perrine Ruby, Inserm Research Fellow said in the news release.
"Our results suggest that high and low dream recallers differ in dream memorization, but do not exclude that they also differ in dream production. Indeed, it is possible that high dream recallers produce a larger amount of dreaming than low dream recallers" the research team said, the news release reported.
