A group of American specialists from Northwestern University in Chicago, Illinois, has developed a technique that allows you to edit human memory during sleep. Scientists have found a way to weaken the associations between odors and memories of an unpleasant and painful electric shock. Details are given in the researchers' article in the journal Nature neuroscience , and a summary is presented in Nature News.

In their work, scientists used the previously discovered effect of memory consolidation during sleep. Numerous experiments on animals, coupled with observational data from psychologists and doctors, indicated that during sleep, memory is restructured from short-term to long-term form: a process called memory consolidation occurs. Other evidence (collected since the middle of the last century) indicated that the impact on memory at this moment can weaken it or completely erase it.

A group of 15 volunteers were exposed during the deep sleep phase (its onset was determined using an electroencephalograph ) to the action of the odor that had previously been associated with an unpleasant, although not dangerous to health, electric shock. The researchers expected that encountering a familiar smell would trigger the consolidation of the traumatic experience, but in a safe environment, during sleep, these memories would become less strong, rather than stronger. A test carried out the next day after sleep showed that the scientists’ calculations were justified.

In order to assess how strong the association was between odor and electric shock, the scientists used two independent methods. First, the volunteers' sweat production was recorded in response to the odor: those who subconsciously expected an electric shock sweated more. Second, this presentation of the odor took place in a functional magnetic resonance imaging scanner, which recorded brain activity in response to the odor: both tests showed that the connection between the odor and the memory of the electric shock became weaker (although it did not disappear completely).

Related materials:

Pillow as a textbook Scientists are again interested in learning in sleep September 12, 2012

The association of certain stimuli (such as smells) with unpleasant memories is an important component of post-traumatic stress disorder, PTSD , and is known as the psychopathological re-experiencing effect . Both doctors and scientists are developing methods to weaken these pathological connections; Progress in this area is associated with increased knowledge of memory consolidation. In addition, the new work is quite closely related to research into the brain’s ability to perceive and process information during sleep: the first studies in this direction were carried out in the first half of the 20th century, but relatively reliable data began to appear in the last two decades.

Human memory learned to edit during sleep