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Lack of sleep slows you down: study- 31-Jul-2012
Researchers from Brigham and Women's Hospital (BWH) have discovered that regardless of how tired you perceive yourself to be 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, senior author of the study.
"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," Duffy said in a statement.
The study was published in the The Journal of Vision.
Researchers collected and analysed data from visual search tasks from 12 participants over a one month study.
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 reported 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 am -6 am, 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," Duffy said.
