(NaturalHealth365)  If you can’t quit misplacing your keys or struggle to remember special dates, a little sleep might help.  A recent study delved deep into the human brain to discover how sleep can improve memory.

The study was the first of its kind in that it recorded electrical activity using electrode probes that had been implanted in the brain.  While the initial purpose of the electrode probes was to explore potential therapies and treatments for seizure disorders, researchers could tap into the technology and incorporate the data they collected into the study.

Study reveals sleep plays a role in consolidation of memory

Although the study was small, the findings were significant.  Participants included five volunteers who were patients at the University of Chicago Epilepsy Center, which partnered with neuroscientists at Northwestern University.  The researchers wanted to study the electrical activity in the brains of the patients and observe how brain activity changed or responded to sounds that the research team administered as part of a learning exercise.

Traditionally, the way the brain processes memory during sleep was done by using EEG recordings that used electrodes attached to the head.  This study was the first of its kind to actually look at the brain’s activity inside the brain.

The remarkable outcome was that although the number of participants in the study was quite small, all five exhibited the very same memory improvement patterns and electrical activity, indicating that sleep contributes to the ability to remember things that a person has learned instead of forgetting them.

Sleep facilitates process of strengthening neural connections that form memories

The study was conducted overnight in a hospital room.  Each patient slept while the research team recorded the brain’s electrophysiological responses to specific sound stimuli that were repeated throughout the night.

The sounds were played all night, but they were very low so that the patients would not wake or be aroused from sleep.  Of the 10 to 20 sounds, half were linked to certain objects and their specific locations that each patient learned on a laptop before going to sleep.

After the patients had slept, they exhibited marked improvements in their spatial recall.  These findings were nearly identical to earlier studies that used EEG recordings via scalp electrodes.  When tested, the patients had increased their accuracy in recalling locations on the computer screens.

Avoid sleep deprivation to enhance your memory 

Object sounds that are presented to the patient while they are sleeping stimulate an increase in oscillatory activity.  This includes increased gamma, sigma, and theta EEG bands.  This electrophysiological activity occurs in the hippocampus as well as the medial temporal area of the patient’s cerebral cortex.  The sounds that were presented to the patient while they were asleep reflected a strengthening and reactivation of spatial memories that corresponded to the sounds, such as keys jangling.

The evidence produced by the brain via electrophysiological response and gamma responses gave researchers a strong link between the enhancement of memory storage that is sleep based and the observation that both brain regions are involved.

While traditionally thought that people block out these sounds while they sleep, researchers now understand that these brain structures not only hear the sounds but respond to them, and those sounds reactivate memories which help in the retention of knowledge during wakefulness.

Sources for this article include:

Medicalxpress.com
PNAS.org