Previous imaging studies have shown that sleep apnea, which causes periods of disrupted breathing during the night, is associated with tissue loss in regions of the brain that process memory. Now new research published in the Journal of Neuroscience offers more evidence that the sleep disorder can cause difficulty in remembering where you left your keys and other daily events.
In a small study (subscription required), people with severe sleep apnea spent two separate nights at the NYU Sleep Disorders Center. At the lab, individuals were administered a baseline examination consisting of playing a video game requiring them to navigate three-dimensional spatial mazes. During one night of the experiment, participants' use of their continuous positive airway pressure (CPAP) machine was reduced during REM sleep allowing sleep apnea to naturally occur. On the second night, they resumed normal use of the CPAP. Individuals played the video game before and after each sleep period.
As Medical News Today reports:
When sleep was aided by therapeutic CPAP all night, researchers observed a 30 percent overnight improvement in maze completion time from their baseline examinations. However, when REM sleep was disrupted by sleep apnea, there was not only no improvement from baseline testing, but, in fact, subjects took 4 percent longer to complete the maze tests.
Equally important, when sleep apnea occurred in REM sleep, subjects did not experience delayed reaction times on a separate test to measure attention, called a psychomotor vigilance test. [Lead researcher Andrew Varga, MD, PhD,] says that this suggests that sleepiness or lack of attention were not reasons for the decline in spatial memory, as indicated by the maze performance after experiencing sleep apnea in REM sleep.
Sleep apnea affects approximately 18 million adults in the United States. While the disorder is difficult to diagnose in children because of monitoring techniques, it's estimated that a minimum of 2 to 3 percent of kids suffer from sleep apnea and some believe it could be as high as 10 to 20 percent, according to data from the National Sleep Foundation.
Previously: “Sleep drunkenness” more prevalent than previously thought, Study shows women with gestational diabetes at increased risk for obstructive sleep apnea, Why untreated sleep apnea may cause more harm to your health than feeling fatigued and How effective are surgical options for sleep apnea?
Photo by Jared Polin