When a physician at a U.S. Department of Veterans Affairs hospital in the Seattle noticed a blood pressure drug was preventing recurring nightmares a UC Berkeley researcher got interested in why. Turns out the drug suppresses the neurotransmitter norepinephrine and that during REM sleep norepinephrine goes down so that the brain can process painful memories in order to take the edge off them the next day. So in the REM sleep state it appears the brain processes emotionally difficult experiences to enable you to better handle these memories the next day.
They say time heals all wounds, and new research from the University of California, Berkeley, indicates that time spent in dream sleep can help.
UC Berkeley researchers have found that 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.
The findings offer a compelling explanation for why people with post-traumatic stress disorder (PTSD), such as war veterans, have a hard time recovering from painful experiences and suffer reoccurring nightmares.They also offer clues into why we dream.
"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 and senior author of the study to be published this Wednesday, Nov. 23, in the journal Current Biology.
A good night's sleep is probably of great enduring value after an emotionally painful day. Make it a point to go to sleep earlier after traumatic experiences.
Stress neurochemicals are suppressed during the REM phase while the brain processes emotionally laden memories.
"During REM sleep, memories are being reactivated, put in perspective and connected and integrated, but in a state where stress neurochemicals are beneficially suppressed," said Els van der Helm, a doctoral student in psychology at UC Berkeley and lead author of the study.
If you can avoid seeing or dealing with the same disturbing images twice while awake you'll be better able to handle the images after you have gotten some sleep.
Thirty–five healthy young adults participated in the study. They were divided into two groups, each of whose members viewed 150 emotional images, twice and 12 hours apart, while an MRI scanner measured their brain activity.
Half of the participants viewed the images in the morning and again in the evening, staying awake between the two viewings. The remaining half viewed the images in the evening and again the next morning after a full night of sleep.
Those who slept in between image viewings reported a significant decrease in their emotional reaction to the images. In addition, MRI scans showed a dramatic reduction in reactivity in the amygdala, a part of the brain that processes emotions, allowing the brain's "rational" prefrontal cortex to regain control of the participants' emotional reactions.
In addition, the researchers recorded the electrical brain activity of the participants while they slept, using electroencephalograms. They found that during REM dream sleep, certain electrical activity patterns decreased, showing that reduced levels of stress neurochemicals in the brain soothed emotional reactions to the previous day's experiences.
Sleep is therapeutic. Drugs can enhance the therapeutic effect. Good to know.
|Share |||Randall Parker, 2011 November 25 06:18 PM Brain Sleep|