The link between sleep quality and intrusive thoughts 🛌

Sleep, often perceived as a simple daily break, plays a much more complex role in our mental balance. A recent study reveals how it acts as a shield against unwanted memories, offering promising perspectives for mental health.


Conducted by the University of East Anglia (UEA), this research explores the brain mechanisms that link sleep to the regulation of intrusive thoughts. The results, published in the Proceedings of the National Academy of Sciences (PNAS), could revolutionize treatments for mental disorders such as depression or post-traumatic stress.

Sleep, a memory regulator

Sleep, particularly REM sleep, appears essential for controlling unwanted memories. Researchers have discovered that well-rested individuals activate the prefrontal cortex more, a key area for managing thoughts and emotions. Conversely, sleep-deprived individuals show increased activity in the hippocampus, linked to memory retrieval, making it more difficult to suppress intrusive thoughts.

The laboratory experiment

The study involved 85 participants, divided into two groups: one having slept normally, the other having stayed awake all night. Using functional magnetic resonance imaging (fMRI), researchers observed that rested participants activated their prefrontal cortex better when asked to get rid of intrusive thoughts. Those who slept longer in REM phase showed better control over their thoughts.

Concretely in this study, participants were subjected to a test aimed at pushing back intrusive thoughts. Images were presented to them in pairs, followed by two instructions: "Think" or "Do not think." In the first case, they had to remember the associated image, while in the second, they had to avoid evoking it. The results showed that rested participants were better at inhibiting unwanted memories, with increased activation of the prefrontal cortex and reduced activity in the hippocampus.

The key role of REM sleep

REM sleep, the phase during which dreams occur, seems to restore memory control mechanisms. Participants who benefited from quality REM sleep were less prone to intrusive memories. This discovery highlights the importance of this phase for emotional resilience and mental health.

Implications for mental health

Mental disorders such as depression or anxiety are often marked by recurrent intrusive thoughts. Understanding how sleep influences these mechanisms opens the way to new therapeutic approaches. Improving sleep quality, particularly REM sleep, could thus become a key strategy to prevent or alleviate these disorders.

To promote restorative sleep, experts recommend maintaining a regular rhythm, creating a conducive environment (darkness, silence, coolness), and avoiding screens before bedtime. Relaxation techniques, such as meditation, can also help prepare the mind for rest.