encounter them feel an alienating vibe that can rub onto them even after a
brief encounter making even well-rested people feel lonely.
‘A novel study has shown that there is a two-way relationship between sleep loss and social isolation, and sheds new light on probably why we see a global loneliness epidemic.’
findings are published in the journal Nature
"We humans are a
social species. Yet sleep
can turn us into social lepers," said study senior
author Matthew Walker, a UC Berkeley professor of psychology and neuroscience.
"The less sleep you get, the less you want to socially interact. In turn,
other people perceive you as more socially repulsive, further increasing the
grave social-isolation impact of sleep loss," Walker added. "That
vicious cycle may be a significant contributing factor to the public health
crisis that is loneliness."
Nearly half of Americans
have reported feeling lonely or left out. Moreover, loneliness increases a
person's risk of mortality (death risk) by more than 45 percent; this figure is
double the mortality risk associated with obesity.
"It's perhaps no
coincidence that the past few decades have seen a marked increase in loneliness
and an equally dramatic decrease in sleep duration," said study lead
author Eti Ben Simon, a postdoctoral fellow in Walker's Center for Human Sleep
Science at UC Berkeley. "Without sufficient sleep we become a social
turn-off, and loneliness soon kicks in."
Walker and Ben Simon conducted a series of intricate experiments using
various tools to gauge the
social effects of poor sleep:
First, they tested the social and neural
responses of 18 healthy young adults after they had a normal night's sleep and
a sleepless night using videotaped simulations that showed them clips of
individuals with neutral expressions walking toward them. The participants
pushed a button to stop the video when they thought the person on the video got
too close. The button recorded how close they allowed the person to get.
Sleep-deprived participants kept the approaching person between 18 and
60 percent further back which was a significantly greater distance away - than
when they had been well-rested.
fMRI brain imaging:
The participants' brains
were scanned as they watched video clips of individuals walking towards them.
The scans showed a heightened activity of social repulsion in a neural circuit
known as the "near space network," in the sleep-deprived brains. This
area is usually activated when the brain perceives potential incoming human
threats or when they feel their
personal space is being invaded.
Also, another circuit of the brain that supports social interaction,
called the "theory of mind" network, was shut down or blunted by
sleep deprivation, and hence aggravating the problem.
Amazon's Mechanical Turk
In this section of the study, more than 1,000 observers were recruited
from the marketplace and shown videotapes of study participants discussing
commonplace opinions and activities.
The observers rated each of the subjects based on how lonely they
appeared, and whether they would be willing to interact socially with them -
all this was done in an unbiased manner as the observers did not know that the
subjects had been deprived of sleep.
Their analysis revealed that the study participants were lonely and less
socially desirable, each and every time.
When the observers were asked to rate their own levels of loneliness
after watching videos of study participants, the answers they got were
surprising - otherwise, healthy observers felt lonely after viewing just a
60-second clip of an alienated person. This proved that sleep-loss-induced
alienation is contagious.
the researchers studied whether just one night of good or bad sleep could
influence a person's sense of loneliness
the next day. They used a standardized
survey to track each person's state of loneliness. Questions like "How
often do you feel isolated from others?" and "Do you
feel you don't have anyone to talk to?" were asked in the survey.
The amounts of sleep a person got from one night to the next clearly
predicted how lonely and unsociable they felt from one day to the next day.
who is also the author of the bestseller, Why We Sleep,
humans are naturally programmed to nurture socially vulnerable members of their
tribe to make their species survive; but, this protective instinct is missing
when they are sleep-deprived. Conditions like starvation have a biological or a
safety net which is lacking in sleep deprivation. Hence, when we lose just one
or two hours of sleep, our physical and mental health implodes very quickly.
"On a positive note, just
one night of good sleep makes you feel more outgoing and socially confident,
and furthermore, will attract others to you.
" Walker said.
- Eti Ben Simon, Matthew P. Walker. Sleep loss causes social withdrawal and loneliness. Nature Communications, 2018; 9 (1) DOI: 10.1038/s41467-018-05377-0