Monday, August 15, 2011

Fragmented Sleep and Memory

Researchers published a study at the end of July in the Proceedings of the National Academy of Sciences about the effect of sleep fragmentation and memory in mice. Studies have shown memory problems can occur when sleep is frequently disrupted. However, scientists are not sure if the memory problems are due to shorter total sleep time, poor sleep quality, reduction in a particular sleep stage (e.g. dream or REM sleep), or from the annoyance of being repetitively awaken.

In this study, the researchers used a new technique to isolate the effects of sleep fragmentation from overall sleep quality. The mice's brains were prodded awake every 60 seconds for one night, and this resulted in measurable memory problems. The interesting part is that the frequent awakenings did not reduce REM or deep sleep percentages, the total amount of sleep, or appear to cause the mice any stress.

The researchers suggest that new skills and information are committed to memory during sleep when our brains replay recently learned actions or sequences. The frequent awakenings interrupt that process such that the memories can be lost or compromised before they are stored.


  1. Dear Dr. Hunter A. Hearn, MD,
    It’s a great pleasure to read your blog. I find your post very informative. This study will surely be beneficial to a lot of people who has been long suffering sleeping problems.
    As a reader, I consider your writing to be a great example of a quality and globally competitive output. It would be a great thrill and honor if you could share your genuine ideas and knowledge to our community, Physician Nexus. With this you can gain 1000 physician readers from over 62 countries on Nexus.
    We would love for you to visit our community. It's free, takes seconds, and is designed for physicians only - completely free of industry bias and commercial interests.
    Janmar Delicana
    On behalf of the Physician Nexus Team

  2. Poor memory was my main symptom when I had undiagnosed OSA. It kept me from having the confidence to go to medical school to become a psychiatrist.

    I am glad to see that I am not alone in my understanding of the connection between fragmented sleep and poor memory.

    Thank you for your vigilance and keeping up with the topics everyone needs to know about.

    Robb Webb, RPSGT