Lack of sleep significantly impairs our ability to stop undesirable and unpleasant thoughts from entering our mind, a new study shows.
The authors of the study say the findings might have implications For individuals suffering from psychiatric conditions related to unwanted thoughts – like post-traumatic anxiety disorder, depression and schizophrenia.
The analysis, from the University of York, analyzed the ability of participants to suppress intrusive thoughts if they had a lack of sleep or were well rested. Sleep deprived participants suffered an increase in undesirable ideas of nearly 50 percent in comparison to people who had a good night’s sleep.
Lead author of the study, Dr Marcus Harrington, from the Department of Psychology at the University of York, said: “In everyday life, mundane encounters can remind us of unpleasant experiences. For example, a car driving too fast on the motorway might cause us to retrieve unwanted memories from a car accident many years ago. For most people, thought intrusions pass quickly, but for those suffering with psychiatric conditions such as post-traumatic stress disorder, they can be repetitive, uncontrollable, and distressing.
“It is clear that the ability to suppress unwanted thoughts varies dramatically between individuals, but until now the factors that drive this variability have been mysterious. Our study suggests sleep loss has a considerable impact on our ability to keep unwanted thoughts out of our minds.”
For the study, sixty healthy participants learned to associate faces with photographs of mentally negative scenes (like an image from a war zone) or impartial scenes (such as an image of a cityscape).
The following morning, after a night of either sleep or lack of sleep, participants were shown the faces and asked to try to suppress ideas related to the scenes with which they had been paired.
Compared to the sleep group, the lack of sleep participants had a whole lot more trouble keeping undesirable thoughts of the emotionally negative and neutral scenes from their minds. While the task became easier with training for the rested participants, for individuals who had gone without sleeping, thought intrusions remained consistently high.
The sleep group’s success at suppressing unwanted thoughts caused them to see the negative scenes more positively after the suppression task, and they showed a reduced sweat response once the negative scenes were introduced. By comparison, the lack of sleep team’s failure to keep undesirable thoughts out of mind meant that they did not experience this positive change in their responses.
Senior author of the study, Dr Scott Cairney, from the Department of Psychology at the University of York, added: “This study offers an important insight into the impact of sleep on mental health. Besides post-traumatic stress disorder and depression, our findings might have implications for our understanding of other disorders linked to sleep disturbances, such as obsessive-compulsive disorder and schizophrenia”.
“The study also suggests that the onset of intrusive thoughts and emotional disturbances following bouts of poor sleep could create a vicious cycle, whereby upsetting intrusions and emotional distress exacerbate sleep problems, inhibiting the sleep needed to support recovery”.
Related Journal Article: https://journals.sagepub.com/doi/10.1177/2167702620951511