Nightmares could be ‘turned off’, new research suggests.
Scientists have discovered two genes that are responsible for nightmares and dreams, which both occur during deep sleep, also known as rapid eye movement (REM).
REM occurs in mammals, including humans, and was thought to play an important role in maintaining their wellbeing, as well as storing memories.
Yet when the researchers removed two genes that cause REM sleep in mice, they were surprised to discover the animals continued to live as normal, despite previous studies suggesting REM is crucial for survival.
By being able to remove the genes that code for dreams in mice, scientists could theoretically prevent people from having nightmares in the future.
Nightmares could be ‘turned off’ after scientists discovered two genes for dreams (stock)
CAN INSOMNIA BE PSYCHOLOGICAL?
Insomnia may be psychological, research suggested in May 2017.
Sufferers who take placebo pills feel more rested than those who get no treatment at all, according to a review of 13 studies.
According to the researchers, the simple act of taking a pill may ease the anxiety that makes it harder for some insomnia sufferers to fall asleep.
Dr Patrick Finan from Johns Hopkins University, who was not involved in the study, said: ‘Insomnia is shaped by expectation and perception, so it is not surprising that placebos, which implicitly alter expectation, are effective in improving perceptions of sleep.’
The researchers, from the University of Sydney, examined data from a total of 566 insomnia sufferers who were assigned to either receive a placebo that they believed was an active treatment or no pills at all.
Placebo patients reported greater improvements in their ability to fall asleep, the total amount of rest they got and their sleep quality.
Comparing placebo against recognised insomnia therapies can give inaccurate results as simply believing you are receiving a sleep-inducing treatment can ease the condition.
Study author Dr Ben Colagiuri, said: ‘The comparison with no treatment means that we can be sure that the improvement we observed was due to a genuine placebo effect, rather than being an artifact of simply taking part in a trial.’
Insomnia may be considered a condition of the mind due to one person averaging four hours sleep a night and feeling sufficiently rested, while another may get seven hours and feel the amount or quality of their shut eye is inadequate, Dr Finan explained.
Deep sleep may not be essential for survival
The researchers, from The University of Tokyo, genetically modified mice so they no longer had genes that coded for the chemical messenger acetylcholine, which is released in high amounts when mammals are in REM sleep.
Removing these genes included knocking out two genes known as Chrm 1 and 3, which are widely distributed across different regions of the brain.
Removing Chrm 1 caused the mice to have short and fragmented periods of REM sleep, while taking out Chrm 3 reduced their length of non-REM shut eye.
When both genes were removed, the mice had almost no REM sleep but still managed to survive.
This was surprising given previous research suggests rats who do not get REM sleep die.
Based on their findings, published in the journal Cell Reports, the researchers believe REM sleep may not be essential for survival, at least in domesticated animals.
Alternatively, mice without Chrm 1 and 3 may have a reduced need for REM sleep, they added.
Do dreams help people cope?
Scientists from Harvard University designed an experiment that determined the extent to which dreams are a precise replay of a person’s recent experiences.
For two weeks, 29 healthy young adults kept a detailed log of daytime activities and their emotional concerns. They also wrote down any dreams they recalled when they woke up.
External judges then systematically compared the reports of the participants’ waking activities with their dreams.
Out of a total of 299 dream reports collected, a clear rerun of prior life events occurred in just 1-to-2 per cent. Dreams are not, therefore, about simply rewinding the video of the day’s recorded experience and reliving it at night.
Yet the researchers did find one strong daytime link with night-time dream reports: emotions. Between 35 and 55 per cent of emotional themes and concerns that participants were having while they were awake during the day powerfully and clearly resurfaced in their dreams.
Dreaming may therefore take the painful sting out of difficult, even traumatic, emotional episodes a person has experienced during the day, offering emotional resolution when they wake the next morning.