During the dream phase of sleep, also known as REM sleep, our stress chemistry shuts down and the brain processes emotional experiences and takes the painful edge off difficult memories. Time spent in dream sleep can help.
“The dream stage of sleep, based on its unique neurochemical composition, provides us with a form of overnight therapy, a soothing balm that removes the sharp edges from the prior day’s emotional experiences,” said Matthew Walker, associate professor of psychology and neuroscience at UC Berkeley.
The results offer some of the first insights into the emotional function of Rapid Eye Movement (REM) sleep, which typically takes up 20 percent of a healthy human’s sleeping hours. Previous brain studies indicate that sleep patterns are disrupted in people with mood disorders such as PTSD and depression.
While humans spend one-third of their lives sleeping, there is no scientific consensus on the function of sleep. However, Walker and his research team have unlocked many of these mysteries linking sleep to learning, memory and mood regulation. The latest study shows the importance of the REM dream state.
Thirty?five healthy young adults participated in the study.
“We know that during REM sleep there is a sharp decrease in levels of norepinephrine, a brain chemical associated with stress,” Walker said. “By reprocessing previous emotional experiences in this neuro-chemically safe environment of low norepinephrine during REM sleep, we wake up the next day, and those experiences have been softened in their emotional strength. We feel better about them, we feel we can cope.”
It turns out that the generic blood pressure drug had a side effect of suppressing norepinephrine in the brain, thereby creating a more stress-free brain during REM, reducing nightmares and promoting a better quality of sleep. This suggested a link between PTSD and REM sleep, Walker said.
“This study can help explain the mysteries of why these medications help some PTSD patients and their symptoms as well as their sleep,” Walker said. “It may also unlock new treatment avenues regarding sleep and mental illness.”
Source: University of California, Berkeley, USA