UC researchers also find that Ambien heightens recollection of, response to bad memories.
Sleep researchers from University of California campuses in Riverside and San Diego have identified the sleep mechanism that enables the brain to consolidate emotional memory and found that a popular prescription sleep aid heightens the recollection of and response to negative memories.
Their findings have implications for individuals suffering from insomnia related to posttraumatic stress disorder (PTSD) and other anxiety disorders who are prescribed zolpidem (Ambien) to help them sleep.
The study — “Pharmacologically Increasing Sleep Spindles Enhances Recognition for Negative and High-arousal Memories” — appears in the Journal of Cognitive Neuroscience. It was funded by a National Institutes of Health career award to Sara C. Mednick, assistant professor of psychology at UC Riverside, of $651,999 over five years.
Mednick and UC San Diego psychologists Erik J. Kaestner and John T. Wixted determined that a sleep feature known as sleep spindles — bursts of brain activity that last for a second or less during a specific stage of sleep — are important for emotional memory.
Research Mednick published earlier this year demonstrated the critical role that sleep spindles play in consolidating information from short-term to long-term memory in the hippocampus, located in the cerebral cortex of the brain. Zolpidem enhanced the process, a discovery that could lead to new sleep therapies to improve memory for aging adults and those with dementia, Alzheimer’s and schizophrenia. It was the first study to show that sleep can be manipulated with pharmacology to improve memory.
“We know that sleep spindles are involved in declarative memory — explicit information we recall about the world, such as places, people and events, ” she explained.
But until now, researchers had not considered sleep spindles as playing a role in emotional memory , focusing instead on rapid eye movement (REM) sleep.