Shaping how we interact with information
For quite some time now, scientists have been aware that there is a link between sleep deprivation and intrusive thoughts. The big question, however, is why that's the case.
According to a new study, the answer has to do with a part of the brain called the right dorsolateral prefrontal cortex. This is the part of the brain that is responsible for suppressing memories, and when it slacks off we tend to suffer from more intrusive thoughts.
Curious? Check out this gallery to find out more.
Someone who struggles with insomnia, on the other hand, may find it difficult to suppress the same memory and it may continue to bother them for a long time.
Until recently, scientists were puzzled as to why exactly sleep deprivation contributes to intrusive thoughts, i.e. what is actually going on in the brain?
Thanks to a recent study published in the journal Proceedings of the National Academy of Sciences USA, we now have more insights.
As previous studies have shown, the rDLPFC is responsible for suppressing the retrieval process of memories. The retrieval itself happens in a different part of the brain: the hippocampus.
The researchers hypothesized that not getting enough sleep inhibits the ability of the rDLPFC to suppress unwanted memories, and therefore contributes to intrusive thoughts.
In order to test their hypothesis, the researchers recruited a group of 85 students and trained them to associate neutral faces with specific images, some of which were negative, such as a car crash.
The aim was for the students to create a mental connection between the faces and the images, so that when they were shown the face in isolation, an automatic memory retrieval process would occur.
The students were then divided into two groups. The first group was made to stay up all night, while the other group was sent to sleep in a lab.
The sleeping students were monitored for how much time they spent in rapid-eye-movement (REM) sleep and non-REM sleep.
In the morning, all the participants were shown images of the faces they had seen in training, and they were asked either to think about the associated memory or repress it.
Throughout the task, researchers used a functional magnetic resonance imaging (fMRI) scanner to measure the students' brain activity.
The fMRI results confirmed the team's hypothesis: compared with the students who had slept, those who stayed up all night had significantly lower rDLPFC activity when they were asked to suppress intrusive thoughts.
In fact, activity in their hippocampus was shown to be elevated, most likely because the rDLPFC was not managing to shut down the retrieval process.
According to Scott Cairney, one of the researchers on the study, these findings do not suggest that sleep deprivation causes a general decline in brain activity.
Rather, the results suggest that not getting enough sleep can negatively affect specific parts of the brain that are involved in executive function.
Another interesting finding of the study was related to the participants who had slept through the night.
Various experts in the field have taken time to give their thoughts on the findings of the study. One such expert is Zara Bergstrom, a cognitive psychologist at the University of Kent in England.
However, she also adds that in order to determine whether REM sleep has a causal role in controlling memories and thoughts, we will need further research that manipulates sleep directly.
According to Maria Wimber, a cognitive neuroscientist at the University of Glasgow, the study results may also have the potential to inform therapeutic approaches.
According to Wimber, treatments that enhance REM sleep could become part of the therapy for disorders that are associated with intrusive thoughts, such as PTSD.
The same interventions may even be used for acute trauma as a possible preventative measure to make sure that upsetting memories and flashbacks never emerge in the first place.
Sources: (Scientific American)
How a lack of sleep can cause intrusive thoughts
A new study reveals a reason for the link
LIFESTYLE Mental health
For quite some time now, scientists have been aware that there is a link between sleep deprivation and intrusive thoughts. The big question, however, is why that's the case.
According to a new study, the answer has to do with a part of the brain called the right dorsolateral prefrontal cortex. This is the part of the brain that is responsible for suppressing memories, and when it slacks off we tend to suffer from more intrusive thoughts.
Curious? Check out this gallery to find out more.