How poor sleep affects mental health could be related to a low function of brain regions that work to keep unwanted, intrusive memories at bay, according to a new study.

Intrusive thoughts and memories, while occasional and momentary for most, can be recurrent, vivid and upsetting for those suffering from mental disorders, such as depression, anxiety and post-traumatic stress disorder, Marcus Harrington, a lecturer of psychology at the University of East Anglia, UK, and lead author of the study published in the journal Proceedings of the National Academy of Sciences, explained.