EMBARGOED FOR RELEASE: June 10, 2009, at 12:01 a.m.

Kelly Wagner
(708) 492-0930, ext. 9331
WESTCHESTER, Ill. – According to a research abstract that will be presented on Wednesday, June 10, at SLEEP 2009, the 23rd Annual Meeting of the Associated Professional Sleep Societies, both men and women rate themselves less positively after awakening from rapid eye movement (REM) sleep, as opposed to non-REM (NREM) sleep. Women seem to be affected more negatively than men.
Results indicate that REM sleep impacts negative affect; in females, REM also may negatively influence autobiographical memories. Latency to retrieve a ‘positive memory’ was significantly longer for females than males after REM versus NREM awakenings (19.84 seconds compared with 11.82 seconds). Negative rating of self versus others after awakenings from REM sleep was associated with impulse control difficulties and daytime depression in both men and women.
According to lead author Sanford Auerbach, MD, at the Boston University School of Medicine, findings of the study were extremely significant, as all the participants in the study were mentally and physically healthy, meaning that effects seen in this population will likely be more pronounced in older people or in clinical groups.
“REM sleep physiology is known to be alerted in mood disorders, particularly in depression,” said Auerbach. “Women tend to suffer from more severe depression than men, because they are more critical of themselves. Findings of this study suggest that the severity of women’s depression may be caused by an excess of REM sleep.”
The study involved 26 males and 29 females with an average age of 21 years. Volunteers were assessed with overnight polysomnography and then awakened from REM and NREM sleep states to perform cognitive tasks. After each awakening, subjects completed self versus ‘significant other’ positive and negative trait rankings and were given tests of mood function and autobiographical memory retrieval.
The annual SLEEP meeting brings together an international body of 6,000 leading researchers and clinicians in the field of sleep medicine to present and discuss new findings and medical developments related to sleep and sleep disorders.
More than 1,300 research abstracts will be presented at the SLEEP meeting, a joint venture of the AASM and the Sleep Research Society. The three-and-a-half-day scientific meeting will bring to light new findings that enhance the understanding of the processes of sleep and aid the diagnosis and treatment of sleep disorders such as insomnia, narcolepsy and sleep apnea.
Abstract Title: Sex differences in sleep-related memory and mood regulation    
Presentation Date: Wednesday, June 10
Category: Behavior, Cognition & Dreams
Abstract ID: 1284