Sleep deprivation could reduce intrusive memories of traumatic scenes | University of Oxford

Sleep deprivation could reduce intrusive memories of traumatic scenes

1 July 2015

A good night’s sleep has long been recommended to those who have experienced a traumatic event. But an Oxford University-led study provides preliminary experimental work suggesting it could actually be the wrong thing to do.

The research, conducted in Oxford’s Wellcome Trust-funded Sleep and Circadian Neuroscience Institute (SCNi) and published in the journal Sleep, showed that sleep deprivation might prevent people from consolidating memories of experimental trauma (emotional film clips in the study), reducing their tendency to experience flashbacks.

Dr Kate Porcheret, from Oxford’s Nuffield Department of Clinical Neurosciences, said: ‘We wanted to see what effect sleep deprivation would have on the development of intrusive memories – what in a clinical setting are called flashbacks. After showing participants a film of scenes with traumatic content, as an analogue to trauma, they were either kept in a sleep laboratory and deprived of sleep or sent home to have a normal night’s sleep in their own bed.’

Each person then kept a diary in which they recorded any intrusive memories, however fleeting, recording as much information as possible so that the research team could check that the intrusive images were linked to the film.

Dr Katharina Wulff, from the SCNi, said: ‘The sleep-deprived group experienced fewer intrusive memories than those who had been able to sleep normally. Both groups experienced more of these involuntary memories in the first two days and a reducing number in the following days. We know that sleep improves memory performance including emotional memory, but there may be a time when remembering in this way is unhelpful.’

The team stress that further research is needed as there is currently limited understanding of intrusive memories of emotional events as well as of the role of sleep in responding to real trauma, and that real-life trauma cannot be directly replicated in an laboratory study.

Dr Porcheret added: ‘Finding out more how sleep and trauma interact means we can ensure people are well cared for after a traumatic event. These are really important research questions to pursue further. For example, it is still common for patients to receive sedatives after a traumatic event to help them sleep, even though we already know that for some very traumatised people this may be the wrong approach. That is why we need more research in both experimental and clinical settings into how our response to psychological trauma is affected by sleep – and lack of sleep too.’

For further information on this study, please contact the University of Oxford News and Information office on news.office@admin.ox.ac.uk or 01865 280533. Or contact the authors, Kate Porcheret at kate.porcheret@ndcn.ox.ac.uk or Katharina Wulff at katharina.wulff@ndcn.ox.ac.uk .

Notes to editors:

The paper, ‘Psychological Effect of an Analogue Traumatic Event Reduced by Sleep Deprivation’, will be published online in the journal Sleep: http://www.journalsleep.org/

Research funders:

The Wellcome Trust
The Wellcome Trust is a global charitable foundation dedicated to improving health. We provide more than £700 million a year to support bright minds in science, the humanities and the social sciences, as well as education, public engagement and the application of research to medicine.

Our £18 billion investment portfolio gives us the independence to support such transformative work as the sequencing and understanding of the human genome, research that established front-line drugs for malaria, and Wellcome Collection, our free venue for the incurably curious that explores medicine, life and art. www.wellcome.ac.uk

The Medical Research Council (MRC)
The Medical Research Council is at the forefront of scientific discovery to improve human health. Founded in 1913 to tackle tuberculosis, the MRC now invests taxpayers’ money in some of the best medical research in the world across every area of health. Thirty-one MRC-funded researchers have won Nobel prizes in a wide range of disciplines, and MRC scientists have been behind such diverse discoveries as vitamins, the structure of DNA and the link between smoking and cancer, as well as achievements such as pioneering the use of randomised controlled trials, the invention of MRI scanning, and the development of a group of antibodies used in the making of some of the most successful drugs ever developed. Today, MRC-funded scientists tackle some of the greatest health problems facing humanity in the 21st century, from the rising tide of chronic diseases associated with ageing to the threats posed by rapidly mutating micro-organisms. www.mrc.ac.uk