Have you observed how some people can remember their dreams so well after waking up almost every morning while for others remembering a dream is a rare incident. Based on how frequently people can recall their dreams, scientists divide them in two categories; people who remember dreams regularly or ‘high dream recallers’ and people who rarely remember the dreams or ‘low dream recallers’. Now why is that difference?
Few months ago a research came out that showed that high dream recallers have twice as many time of wakefulness during sleep and their brains respond more to Auditory Stimuli both during sleep and wakefulness. The period of wakefulness enables them to memorize the dreams better.
To show why does that happen researchers at INSERM, France classified people into two groups. A group of 21 People who could recall dreams with an average of 5.2 mornings per week and a group comprising of 20 people who could on average recall 2 dreams a month. Scientists used Positron Emission Tomography (PET) to measure the spontaneous brain activity of the subjects, during wakefulness and sleep.
The high dream recallers, both while they were asleep and awake, showed stronger brain activity in the Medial Prefrontal Cortex (mPFC) and in Temporo-perietal Junction (TPJ). This area of brain is involved in attention orienting towards external stimuli. This also explains the earlier research that concluded that the lesions in these two parts of the brain causes a person to altogether cease dream recalling.
To memorize something, the brain must be awake and in high dream recallers stronger activity of brain that causes them to react to external stimuli and wake up many times for a brief period during sleep, enables them to remember their dreams more efficiently while a brain with less activity in those parts, which cannot react to stimuli will not be able to memorize any dreams.
That is the difference in high and low dream recallers, but there might also be another reason that high dream recallers possibly produce more dreams than low dream recallers. Further research is needed to prove if that is true but at least now you know why you can or cannot remember your dreams. [ INSERM ; Image via art2work]