A period of rest following a traumatic event can boost mental recovery from negative memories, according to a study which may help develop new treatment approaches for Post Traumatic Stress Disorder (PTSD). The study, published in the journal Scientific Reports, revealed the neurological mechanisms at play when some people develop memory disturbances following trauma, while others do not.
The researchers, including those from University College London (UCL) in the UK, presented 85 participants with emotionally negative videos, after which they were either given a period of wakeful rest, or a simple control task requiring them to pay attention to numbers on a screen. The videos had highly emotional content such as badly injured people, or serious accidents, the study noted.
According to the researchers, participants who had a period of rest after viewing the videos reported fewer memory intrusions over the following week. On the contrary, there was no difference between rest and the simple control task on a memory test that assessed how much the participants remembered when they wanted to.
The researchers mentioned that rest and certain phases of sleep increased processing in the hippocampus -- the brain region responsible for memory, which placed memories in context. They suggested that a strengthening of this contextual memory system was beneficial in preventing involuntary memory intrusions following trauma.
"The coherence of memories is often compromised when people are exposed to psychological trauma, resulting in emotional memories popping up involuntarily and out of context," said co-author Neil Burgess of UCL. However, Burgess added that the binding of an event memory with its context may be partly restored with rest, facilitating deliberate control of the memory.
The researchers mentioned that specific brain systems could be targeted to reduce the development of PTSD, as treatments focusing on re-exposure and integrating the trauma with other information are beneficial. "Our findings contribute to a better understanding of the mechanisms that are at play when some people develop memory disturbances following trauma while others do not," said co-author of the study Lone Horlyck from UCL.