Sleep Disruptions Worse For Mood Than Shortened Sleep Periods


A small study has confirmed what lots of very tired people already know – having your sleep interrupted several times a night can leave you feeling worse than sleeping, uninterrupted, for a too-short period of time.  

The Study

The Johns Hopkins Medicine study, reported in the journal “Sleep,” examined the difference between getting enough sleep, getting too little sleep and forced awakenings upon the moods of 62 healthy men and women who had no reported history of sleep pattern problems.

The 62 study participants were separated into three groups and observed over the course of three nights. Some were allowed to sleep uninterrupted. Others were given delayed bedtimes, meant to limit their sleep time considerably. The third group experienced eight forced awakenings during each night’s slumber. The experiment, which relied upon a standard mood assessment questionnaire, took place in an inpatient, clinical setting.

After the first night and not surprisingly, the participants who got the most sleep suffered no apparent, ill effects to their feelings of cheerfulness or happiness. The other two groups did not fare quite as well, with both groups reporting similar, slight declines in feelings of cheerfulness  

After the second night, a larger mood shift occurred among participants in the three groups. The delayed bedtime group reported a 12 percent decline in positive mood but the forced awakenings group reported a whopping 31 percent reduction in positive mood, strongly suggesting that the effects of fragmented sleep are cumulative, as well as deleterious.

How Fragmented Sleep Affects the Brain  

Your brain needs time to progress through multiple stages of sleep before it can progress to slow-wave sleep. The Liberty Center for Sound Sleep defines slow-wave sleep as the deep sleep needed by the brain and body to rest and become energized and nourished. When sleep is interrupted, or fragmented, this deep stage of slow-wave sleep can remain elusive, robbing the body and brain of the ability to truly become rested or rejuvenate itself.    

Who is Most Affected by Fragmented Sleep?

According to the study’s researchers, on-call health care workers and parents of small babies or very young children may experience some of the highest levels of fragmented sleep.

Insomniacs, who make up around 10 percent of the population, are also at risk of experiencing higher-than-average levels of fragmented sleep. Individuals with insomnia are also thought to experience higher levels of depression than the general population. While much is still not understood about both insomnia and depression, it is possible that fragmented sleep and its impact upon positive mood may be part of the problem.

New parents can look forward to a day when their children will let them sleep and on-call workers can opt to change jobs, or shifts. Those suffering from insomnia should discuss possible cures with their physician, including holistic treatments or medications which can help. Setting the stage for restful sleep by relaxing, turning off electronics or meditating may also be of benefit.