Researchers have identified a neural link between depression and sleep problems for the first time by finding functional connectivity between the areas of the brain associated with short-term memory, self, and negative emotions.
The study by researchers at the University of Warwick (UK) and Fudan University (China) could lead to better sleep quality for people with depression, and opens up the possibility of new targeted treatments.
For the study researchers analysed data from around 10,000 people, the researchers examined the neural mechanisms underlying the relation between depression and quality of sleep. In the brains of those living with depressive problems, they discovered a strong connection between the dorsolateral prefrontal cortex (associated with short-term memory), the precuneus (associated with the self) and the lateral orbitofrontal cortex (associated with negative emotion). The analysis showed that these functional connectivities underlie the relation between depressive problems and sleep quality.
Based on their findings, scientists concluded that increased functional connectivity between these brain regions provides a neural basis for how depression is related to poor sleep quality.
Depression and sleep problems often go hand-in-hand. About 75% of depressed patients report significant levels of sleep disturbance, such as difficulty of falling asleep and short duration of sleep (insomnia). People with insomnia also have a higher risk of developing depression and anxiety than those who sleep normally.
Professor Jianfeng Feng, from the University of Warwick’s Department of Computer Science, said:
“The understanding that we develop here is consistent with areas of the brain involved in short-term memory (the dorsolateral prefrontal cortex), the self (precuneus), and negative emotion (the lateral orbitofrontal cortex) being highly connected in depression, and that this results in increased ruminating thoughts which are at least part of the mechanism that impairs sleep quality.”