July 28, 2012
Do you get the recommended 8-10 hours of sleep a night? Some of us shrug off the missed hours as something that won't hurt productivity. If there's a sense of fatigue we can work harder and longer with an energy drink or coffee shot.
But a recent study out of The Journal of Vision may change your perception of how much sleep you need. A team of researchers at Brigham and Women’s Hospital (BWH) have discovered that regardless of how energized you feel, that lack of sleep can influence the way you perform certain tasks. “Our team decided to look at how sleep might affect complex visual search tasks, because they are common in safety-sensitive activities, such as air-traffic control, baggage screening, and monitoring power plant operations,” explained Jeanne F. Duffy, PhD, MBA, senior author on this study and associate neuroscientist at BWH. “These types of jobs involve processes that require repeated, quick memory encoding and retrieval of visual information, in combination with decision making about the information.”
Researchers collected and analyzed data from visual search tasks from 12 participants over a period of one month. In the first week, all participants were scheduled to sleep 10-12 hours per night to make sure they were well-rested. For the following three weeks, the participants were scheduled to sleep the equivalent of 5.6 hours per night, and also had their sleep times scheduled on a 28-hour cycle, mirroring chronic jet lag. The research team gave the participants computer tests that involved visual search tasks and recorded how quickly the participants could find important information, and also how accurate they were in identifying it. The researchers report that the longer the participants were awake, the more slowly they identified the important information in the test. Additionally, during the biological night time, 12 a.m. -6 a.m., participants (who were unaware of the time throughout the study) also performed the tasks more slowly than they did during the daytime.
“This research provides valuable information for workers, and their employers, who perform these types of visual search tasks during the night shift, because they will do it much more slowly than when they are working during the day,” said Duffy. “The longer someone is awake, the more the ability to perform a task, in this case a visual search, is hindered, and this impact of being awake is even stronger at night.”
(Story materials via Brigham and Women's Hospital.)