Not getting enough sleep may open the door to negative, intrusive thoughts

If you often struggle with unwanted negative or otherwise unpleasant thoughts, the reason may be due to poor sleep quality. That's according to a new study from the University of York, which reports that sleep-deprived individuals are less capable of suppressing negative and unwanted thoughts compared to those who get enough sleep, potentially making existing psychiatric issues worse.

The new study involved 60 participants who were healthy and were tasked with associating portraits with either neutral scenes or negative scenes. The participants were then subjected to either a proper night of sleep or sleep deprivation. In this rested or sleep-deprived state, the participants were then shown the images of faces and instructed to suppress the thoughts they have related to the photos.

The sleep-deprived group found it harder to suppress the unwanted thoughts — and, unlike with the rested participants, the sleep-deprived subjects struggled to block out these intrusive thoughts even with practice.

In addition, the sleep-deprived group didn't experience any sort of positive change in their perception of the negative scenes over time, as did the rested group. The findings underscore the importance of getting proper, healthy sleep for mental health, with the researchers noting that sleep deprivation may exacerbate the emotional issues and intrusive thoughts experienced with conditions like PTSD and OCD.

Dr. Marcus Harrington, the study's lead author, explained:

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.