Bizarre behaviours that we accidentally carry out while asleep aren’t just limited to walking and talking.
In fact, a new study has compiled 10 different ‘parasomnias’ – the various sleep disorders that consist of ‘undesirable physical displays’.
They include talking, walking, moving hands, laughing or crying, and aggressive movements like hitting and kicking.
But more bizarre activities while asleep include eating, ‘handling sharp objects’, having sex and even driving, the researchers say.
Public awareness is growing of ‘sexsomnia’ – unintentionally initiating sex during sleep – which is said to mostly affect men.
Researchers have revealed the top 10 different activities people unintentionally do when asleep – known as ‘parasomnias’
Driving as a parasomnia is different from people getting into a car while awake and falling asleep at the wheel (file photo)
The new study was led by researchers at Semmelweis University in Budapest, Hungary and published in the Journal of Clinical Neuroscience.
‘Sitting up, getting out of bed, and walking around are typical in the so-called non-rapid eye movement (NREM) parasomnias, which mostly happen in the deep sleep stage of the sleeping cycle,’ said first author Vivian Correa.
‘In this case, the person straddles between sleep and wakefulness.
‘That may sometimes be associated with handling sharp objects, leaving home or driving.
‘The half-sleeping person may eat or even perform sex.’
Unintentionally having sex during sleep, (sexsomnia) may be related to external factors such as stress and alcohol, according to the Sleep Foundation.
Often, those who experience the disorder wake up during intercourse and feel confusion about how it started.
It can also throw up issues regarding consent, which can land people in criminal courts.
Unintentionally having sex during sleep, (sexsomnia) may be related to external factors such as stress and alcohol, according to the Sleep Foundation (stock image)
Meanwhile, driving as a parasomnia is different from people getting into a car while awake and falling asleep at the wheel.
Rather, sufferers get out of bed, go outside to the car and start the engine – all while still asleep.
Violence and even murder performed during sleep have been previously described in the academic literature, and while comparatively rare, they also issues regarding accountability.
For the study, researchers searched various terms relating to unintentional sleep activities on YouTube between January and July 2022.
These terms included ‘sleepwalking’, ‘somnambulism’, ‘sleep eating’, ‘sleep sex’, ‘sleep talking’, and ‘aggression in sleep’.
After an initial 758 results, they selected 224 videos of people engaging in the unintentional sleep activities – 68 children, 40 elderly adults and 116 young adults.
Overall, the top three behaviours were sleeptalking (either full sentences or gibberish), emotional behaviours like crying and laughing, sleepwalking, and random hand movements.
In humans, sleep is generally separated into ‘non rapid eye movement’ or NREM sleep and rapid eye movement or REM sleep. A typical night’s sleep goes back and forth between the stages
Analysis of the people in the videos also showed the elderly had significantly lower odds of sleepwalking compared to adults and children.
But elderly males had 40-fold odds compared with adults and children to perform aggressive movements in bed.
Elderly people showed emotional behaviors such as crying less frequently than adults, and females showed them twice as often as males.
Interestingly, females had more than double the odds of performing complex manual activities compared to males, such as handling electricity or kitchen tools.
Similarly hazardous behaviours, such as leaving the house or driving while sleepwalking, were also significantly lower in the elderly.
And adults sleep-talked full sentences more often than children and elderly people – possibly because at this stage of life we have more on our mind.
Although the exact cause of sleeptalking is unclear, it may be due to stress or mental health conditions, the Sleep Foundation claims.
Sleep disorders affect 10 to 15 per cent of children, the experts say, but most grow out of them.
As a result, sleep disorders are less common in adulthood (three to four per cent) and even rarer in old age.
However, sufferers usually seek medical attention after challenging or traumatic sleep episodes, which could prove fatal.
The researchers hope their results will increase awareness of age-related and sex-related risk factors.
Generally, people can reduce the risk of parasomnias by trying to eliminate stress and anxiety, sleep deprivation and alcohol intake.
‘We identified sleep-related behavior patterns apparently consistent with parasomnias across age and sex groups, promising to improve ways of risk management,’ the team conclude.
Although they admit the limitations of just studying YouTube videos, with no demographic or historical data, they call more comprehensive methods for future studies.