We look into the latest articles on sleep and fatigue to interpret them for our audience and WOMBATT-VOZ users, in order to make sure that you can benefit from the latest sleep research for your personal fatigue management. We recently came across an interesting research which dives into the relation between sleep and decision making. Here is some food for thought..

Question: What is the effect of sleep deprivation on response error in a fast changing situation?

Background

Many of the most well-known cases of fatal accidents due to sleep deprivation were proven to be caused by a sleep deprived condition known as “Cognitive Tunnel Vision”, or an inability to think quickly outside the box. These incidents include the BP Texas City explosion in 2005, the USS John S McCain accident in Singapore in 2017, and the Latam Airlines accident at Lima Airport in Peru in 2022.  Recent research (July 2023) conducted with the US Air Force by Washington State University in the US and Monash University in Australia has shown that sleep deprived persons also respond less accurately to fast changing situations than well rested people. So in addition to being less able to recognize a fast changing situation, tired people tend to make the wrong choices when they do actually react to a dynamic situation.

Research Results

Sleep deprivation research shows that some cognitive functions such as working memory and semantic encoding (using memory to understand a dynamic situation via experience or training), are less affected by sleep deprivation. In other words, performance in carrying out familiar tasks is less affected by sleep loss than performance in unfamiliar tasks. But when the task requires a fast response to a dynamic situation, the risk of errors and accidents is significantly higher in a sleep deprived person than with a well rested person. 

In operational settings, workers and drivers often face the need to balance competing task demands, such as maintaining performance accuracy while negotiating time pressure. Very often, the requirement is to react both accurately and fast. In the research, people in the well rested condition were able to handle both requirements – speed and accuracy – reasonably well. By contrast, people in a sleep deprived condition experienced increased errors. In a surprising twist, sleep deprived people often actually react faster than well rested people, but are then more often wrong.  Tasks that require significant attentional control to perform well, such as driving, operating machinery, or as in the research, flying military aircraft, are especially sensitive to sleep loss error when time pressure is involved. Sleep deprived drivers of semi-autonomous vehicles may be highly prone to error under fast changing road conditions when the vehicle suddenly hands back control to the driver.