Lack of sleep can make a person selfish, reveals study

ANI

California (US), August 24

Humans help one another; it is one of the pillars of civilised society. However, a new study conducted by scientists at the University of California, Berkeley, reveals that a lack of sleep impairs this fundamental human trait, with real-world consequences.

Sleep deprivation has been linked to an increased risk of cardiovascular disease, depression, diabetes, hypertension, and overall mortality. These new findings, however, show that a lack of sleep also impairs our basic social conscience, causing us to withdraw our desire and willingness to help others.

In one section of the new study, the researchers found that charitable giving dropped by 10% in the week following the start of Daylight Saving Time, when residents in most states “spring forward” and lose one hour of their day—a drop not seen in states that do not change their clocks or when states return to standard time in the fall.

The study, led by UC Berkeley research scientist Eti Ben Simon and Matthew Walker, a UC Berkeley professor of psychology, adds to a growing body of evidence demonstrating that insufficient sleep not only harms an individual’s mental and physical well-being but also jeopardises interpersonal bonds and even the altruistic sentiment of an entire nation.

“We have discovered a very intimate link between our sleep health and our mental health over the last 20 years.”

“We haven’t found a single major psychiatric condition in which sleep is normal,” Walker said. “However, this new research shows that a lack of sleep not only harms an individual’s health, but also degrades social interactions between individuals and, ultimately, the fabric of human society itself.” How we function as a social species—and we are a social species—appears to be profoundly dependent on how much sleep we get.”

“We’re seeing more and more studies, including this one, where the effects of sleep deprivation don’t just stop at the individual, but spread to those around us,” Ben Simon said. “Not getting enough sleep not only harms your own well-being, but it also harms the well-being of your entire social circle, including strangers.”

Ben Simon, Walker, and their colleagues Raphael Vallat and Aubrey Rossi will publish their findings in the open access journal PLOS Biology on August 23. Walker is the Center for Human Sleep Science’s director. He and Ben Simon are both members of UC Berkeley’s Helen Wills Neuroscience Institute.

Sleeplessness dampens the theory of mind network.

The new report describes three separate studies that looked at how sleep deprivation affects people’s willingness to help others. In the first study, the researchers scanned the brains of 24 healthy volunteers using a functional magnetic resonance imager (fMRI) after eight hours of sleep and after a night of no sleep. They discovered that after a sleepless night, areas of the brain that form the theory of mind network, which is engaged when people empathise with others or try to understand other people’s wants and needs, were less active.

“When we think about other people, this network engages and allows us to understand what their needs are: What are they thinking about?” Are they in any discomfort? “Do they require assistance?” According to Ben Simon. “However, when individuals were sleep deprived, this network was significantly impaired.” It’s as if these areas of the brain don’t respond when we try to interact with others after not getting enough sleep.”

They tracked more than 100 people online over three or four nights in a second study. During this time, the researchers assessed their desire to help others by measuring the quality of their sleep—how long they slept, how many times they woke up—and then holding an elevator door open for someone else, volunteering, or helping an injured stranger on the street.

“We discovered that a decrease in sleep quality from one night to the next predicted a significant decrease in desire to help others from one subsequent day to the next,” Ben Simon explained. “Those who had a bad night’s sleep the night before reported being less willing and eager to help others the next day.”

The study’s third component involved mining a database of 3 million charitable donations made in the United States between 2001 and 2016. Did the number of donations increase or decrease following the implementation of Daylight Saving Time and the potential loss of an hour of sleep? They discovered a 10% decrease in donations. This drop in charitable giving was not seen in areas of the country that did not change their clocks.

“Even a very modest ‘dose’ of sleep deprivation—in this case, the loss of one single hour of sleep opportunity due to daylight saving time—has a very measurable and very real impact on people’s generosity and, thus, how we function as a connected society,” Walker said. “Losing one hour of sleep has a clear impact on our innate human kindness and motivation to help others in need.”

An earlier study by Walker and Ben Simon found that sleep deprivation caused people to withdraw socially and become socially isolated. Their feelings of loneliness were exacerbated by a lack of sleep. Worse, when those sleep-deprived people interacted with others, they spread their loneliness to them, almost like a virus, according to Walker.

 “Looking at the big picture,” he said, “we’re starting to see that a lack of sleep results in a quite asocial and, from a helping perspective, anti-social individual, which has numerous consequences for how we live together as a social species.” “Lack of sleep makes people less empathetic, less generous, and more socially withdrawn, and it’s contagious—loneliness spreads.”

“The realisation that the quantity and quality of sleep affects an entire society as a result of a deficit in prosocial behaviour may provide insights into our current societal state of affairs,” Walker added.

This discovery also suggests a novel approach to improving these particular aspects of our society.

“Instead of shaming people for not sleeping enough, promoting sleep could very visibly help shape the social bonds we all experience every day,” Ben Simon said.

“It turns out that sleep is a fantastic lubricant for prosocial, connected, empathic, kind, and generous human behaviour.” “If there was ever a need for a strong, prosocial lubricant to enable the very best version of ourselves within society, now appears to be it,” Walker, author of the international bestseller Why We Sleep, said. “Sleep may be a wonderful ingredient that enables the speed with which humans help one another.”

“Sleep is necessary for all aspects of our physical, mental, and emotional lives,” said Ben Simon. “When sleep is undervalued in society, we not only get sleep-deprived doctors, nurses, and students, but we also suffer on a daily basis from unkind and less empathic interactions.”

More than half of all people in developed countries report getting insufficient sleep during the work week.

“As a society, it is time to abandon the notion that sleep is unnecessary or a waste and, without feeling embarrassed, begin getting the sleep that we require,” she added. “It is the best kind of kindness we can offer ourselves and those around us.”