Often, people believe it is the amount of sleep that matters, when in fact, our cognitive abilities also depend on the quality of sleep we receive. There are many reasons a person may awaken during the night whether to go to the bathroom, toss and turn, or to soothe a crying baby. When these interruptions take place, your deep sleep cycle is affected.
A recent study conducted by researchers at the University of Pittsburgh showed an impairment of cognitive abilities in elderly subjects when their sleep was disrupted. Of the 62 subjects, one group was allowed eight hours of sleep for three consecutive nights, but each hour they were awakened for 20 minutes. This group was also awakened for an entire hour on the eighth hour, which was not always at the same time each night.
The other group had only a delayed bedtime each night. Participants from both groups experienced a decline in their mood. Initially, evidence of this study raises the question, are fewer, consolidated hours of sleep better for you than a longer nights’ sleep that consists of many interruptions?
In 2014, a study published in the journal Psychology and Aging, assistant professor of psychiatry at the University of Pittsburg School of Medicine, Kristine Wilckens, along with her co-researchers, conducted a study on 59 young adults and 53 older adults. All participants wore accelerometers on their arms. This device was able to measure whether or not the participants were sleeping throughout the course of the study, which lasted a week.
In conclusion, the researchers determined that whenever participants experienced a disruptive sleep pattern, their cognitive abilities suffered, specifically verbal fluency and memory recall. For the older adults, the amount of sleep time did not influence their cognitive ability.
Does this mean older adults do not require as much sleep each night? Not necessarily, another study conducted by Tel Aviv University assessed 61 adults by allowing one group only four hours of sleep a night, the second group was allowed eight hours. Participants in both groups were awakened every 90 minutes by receiving a phone call, and then they had to send an email to complete a particular 10-minute task that they were given. The results of this study showed that regardless of how much or how little sleep the participants received, both groups experienced issues sustaining their attention, made more errors in their tasks, and had an increase of fatigue, confusion, and depression as compared to receiving a normal, uninterrupted night of sleep.
If you have a difficult time focusing on your daily tasks, consider the quality of your sleep. Even though you may go to bed early and feel as though you have slept enough hours at night, your sleep may be interrupted without you even realizing. You may even suffer from an underlying sleep disorder. Consider a sleep evaluation if you feel as though you are not sleeping the way you should.
Reddy, S. (2015, November 30). A Good Night’s Sleep Is Tied to Interruptions, Not Just Hours. The Wall Street Journal. Retrieved from https://www.wsj.com/articles/a-good-nights-sleep-is-tied-to-interruptions-not-just-hours-1448907227