Northwestern University LogoThis news presents an interesting insight on our sleep during night. Even though we are in a deep sleep, sounds like a dog’s bark or a tea-kettle whistle can apparently be somehow heard by us subconsciously. The 25 sounds presented during the nap to the participants of Northwestern University were apparently reminders of former spatial learning, although the subjects claimed to be ignorant of the sounds as they slept.

Nevertheless, upon waking, memory tests illustrated that spatial memories were apparently distorted. The participants were said to be more precise in dragging an item to the right position on a computer screen for the 25 images whose equivalent sounds were provided during sleep for instance, a stifled blast for an image of dynamite than for another 25 matched objects.

John Rudoy, lead author of the study and a neuroscience Ph.D. student at Northwestern, commented, “The research strongly suggests that we don’t shut down our minds during deep sleep. Rather this is an important time for consolidating memories.”

Most provocatively, the research demonstrated that sounds could infiltrate deep sleep and be used to direct practice of definite information, thereby supposedly pushing people’s consolidation of memories in one course over another.

Ken Paller, senior author of the study and professor of psychology in the Weinberg College of Arts and Sciences at Northwestern, commented, “While asleep, people might process anything that happened during the day — what they ate for breakfast, television shows they watched, anything. But we decided which memories our volunteers would activate, guiding them to rehearse some of the locations they had learned an hour earlier.”

The Northwestern research includes a novel twist to a growing body of research illustrating that memories are apparently processed during sleep. This apparently shows that the brain is quite busy during sleep, going over lately gained information and incorporating it with other knowledge in an inexplicable consolidation process that supposedly preserves our memory capacities when awake.

Whether or not memories are processed during sleep apparently has been a topic of debate. This is because most of the research was concentrating on REM which is said to be a standard stage of sleep defined by rapid movement of the eyes. Intensely recalled dreams are believed to typically arise during REM sleep. Current research, counting the new Northwestern study, nevertheless, centers on memory processing during deep sleep, than during REM sleep.

Before their naps, the 12 subjects were apparently trained to connect all the 50 pictures with a random position on a computer screen. Every item like a crushing wine glass was matched with an equivalent sound like that of breaking glass, provided by a speaker.

Locations were supposedly studied by repeating trials until participants got quite good in positioning all the items in their allocated places. About 45 minutes following learning, every participant reclined in a silent, dark room. Electrodes fastened to their scalp gauged their brain activity when they were asleep.

Sleep sounds were said to be offered without waking anyone up. When questioned later, none of the participants were aware that sounds had been played during the naps. Nevertheless, memory supposedly exhibited that placement of the objects appeared to be more precise for those cued by their related sounds during sleep as compared to those who were not cued.

‘Strengthening Individual Memories by Reactivating Them During Sleep’ was published in the journal Science.