There's Another Side Effect Of Sleep Deprivation (And You're Not Going To Like It)

Restless nights can make you selfish, it seems.
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Most of us know that not getting enough hours of sleep has negative side effects. Sleep deprivation can lead to high blood pressure, diabetes and heart failure, as well as depression, a reduced immune system and a lower sex drive.

Now, a new study has found that losing just one of hour sleep could kill people’s desire to help others, including relatives and close friends.

Sleep deprivation was found to lessen the part of the brain that encouraged social behaviour, the study found. The team, who wrote in PLoS Biology journal, highlighted that continuous lack of sleep could negatively effect social bonds and compromise the altruistic instincts that shape society.

“We discovered that sleep loss acts as a trigger of asocial behaviour, reducing the innate desire of humans to help one another,” said Prof Matthew Walker, co-author of the study at the University of California, Berkeley. “In a way, the less sleep you get, the less social and more selfish you become.”

The researchers analysed 160 participants to test how willing they were to help others with a “self-reported altruism questionnaire” which was completed after a night’s sleep. Participants responded to different social scenarios on a scale from “I would stop to help” to “I would ignore them”.

One experiment involved 24 participants, and researchers compared answers from the same person after having a full nights sleep and after 24 hours without sleep. The answers revealed a 78% decline in self-reported eagerness to help others when tired.

After this. the team carried out brain scans of those participants which found that having a restless nights sleep is associated with reduced activity in the social cognitive brain network, a region involved in social behaviour.

“A lack of sleep impaired the drive to help others regardless of whether they were asked to help strangers or close relatives. That is, sleep loss triggers asocial, anti-helping behaviour of a broad and indiscriminate impact,” said Prof. Walker.

Professor Russell Foster, director of the Sleep and Circadian Neuroscience Institute at the University of Oxford, who was not involved in the study, said: This is the first study to show unambiguously that sleep loss can reduce the tendency of individuals to help one another.

“These findings have major implications across all levels of society but particularly for our night shift, frontline staff.

Doctors, nurses and the police are often chronically tired, and the findings suggest that their ability to help under difficult and demanding circumstances may be compromised.”