Nav: Home

Sleep deprivation impairs ability to interpret facial expressions

March 23, 2017

After a rough night's sleep, your ability to recognize whether those around you are happy or sad could suffer, according to a study led by a University of Arizona psychologist.

The research, published in the journal Neurobiology of Sleep and Circadian Rhythms, found that study participants had a harder time identifying facial expressions of happiness or sadness when they were sleep deprived versus well-rested.

The sleepy participants' ability to interpret facial expressions of other emotions -- anger, fear, surprise and disgust -- was not impaired, however. That's likely because we're wired to recognize those more primitive emotions in order to survive acute dangers, said lead researcher William D.S. Killgore, a UA professor of psychiatry, psychology and medical imaging.

While emotions such as fear and anger could indicate a threat, social emotions such as happiness and sadness are less necessary for us to recognize for immediate survival. When we're tired, it seems we're more likely to dedicate our resources to recognizing those emotions that could impact our short-term safety and well-being, Killgore said.

"If someone is going to hurt you, even when you're sleep deprived you should still be able to pick up on that," Killgore said. "Reading whether somebody is sad or not is really not that important in that acute danger situation, so if anything is going to start to degrade with lack of sleep it might be the ability to recognize those social emotions."

The data used in the study was part of a larger research effort on sleep deprivation's effects on social, emotional and moral judgment. Killgore began the project while working as a research psychologist for the U.S. Army.

The current study is based on data from 54 participants, who were shown photographs of the same male face expressing varying degrees of fear, happiness, sadness, anger, surprise and disgust. Participants were asked to indicate which of those six emotions they thought was being expressed the most by each face.

In order to assess participants' ability to interpret more subtle emotional expressions, the images presented were composite photos of commonly confused facial expressions morphed together by a computer program. For example, a face might show 70 percent sadness and 30 percent disgust or vice versa. Participants saw a total of 180 blended facial expressions at each testing session.

Participants' baseline responses to the images were compared to their responses after they were deprived of sleep for one night.

Researchers found that blatant facial expressions -- such as an obvious grin or frown (90 percent happy or 90 percent sad) -- were easily identifiable regardless of how much sleep a participant got. Sleep deprived participants had a harder time, however, correctly identifying more subtle expressions of happiness and sadness, although their performance on the other emotions was unchanged.

When participants were tested again after one night of recovery sleep, their performance on happiness and sadness improved, returning to its baseline level.

While the difference in performance was not overwhelming, it's enough that it could have a significant impact in critical social interactions, Killgore said.

"As a society, we don't get the full seven to eight hours of sleep that people probably need to be getting. The average American is getting a little less than six hours of sleep on average, and it could affect how you're reading people in everyday interactions," Killgore said. "You may be responding inappropriately to somebody that you just don't read correctly, especially those social emotions that make us human. Or you may not be as empathic. Your spouse or significant other may need something from you and you're less able to read that. It's possible that this could lead to problems in your relationships or problems at work. To me, that is one of the biggest problems -- how this affects our relationships."

Killgore's research builds on existing work on the effects of sleep deprivation on the brain's ventromedial prefrontal cortex -- an area that helps people make judgments and decisions using their emotions.

A prior study, published by Harvard's Seung-Schik Yoo and colleagues, showed that when people are sleep deprived, a disconnect occurs between the prefrontal cortex and the amygdala -- one of the key emotionally responsive areas of the brain.

"So, in simplistic terms, the part of the brain that controls your emotions and the part that sees faces and responds to the emotional content basically start to lose their ability to communicate," Killgore said. "We wanted to test that out and see if it plays out in terms of how people read facial expressions -- and, in fact, it looks like it does."
-end-


University of Arizona

Related Sleep Articles:

Chronic opioid therapy can disrupt sleep, increase risk of sleep disorders
Patients and medical providers should be aware that chronic opioid use can interfere with sleep by reducing sleep efficiency and increasing the risk of sleep-disordered breathing, according to a position statement from the American Academy of Sleep Medicine.
'Short sleep' gene prevents memory deficits associated with sleep deprivation
The UCSF scientists who identified the two known human genes that promote 'natural short sleep' -- nightly sleep that lasts just four to six hours but leaves people feeling well-rested -- have now discovered a third, and it's also the first gene that's ever been shown to prevent the memory deficits that normally accompany sleep deprivation.
Short sleep duration and sleep variability blunt weight loss
High sleep variability and short sleep duration are associated with difficulties in losing weight and body fat.
Nurses have an increased risk of sleep disorders and sleep deprivation
According to preliminary results of a new study, there is a high prevalence of insufficient sleep and symptoms of common sleep disorders among medical center nurses.
Opioids are not sleep aids, and can actually worsen sleep research finds
Evidence that taking opioids will help people with chronic pain to sleep better is limited and of poor quality, according to an interdisciplinary team of psychologists and medics from the University of Warwick in partnership with Lausanne University Hospital, Switzerland.
Common sleep myths compromise good sleep and health
People often say they can get by on five or fewer hours of sleep, that snoring is harmless, and that having a drink helps you to fall asleep.
Sleep tight! Researchers identify the beneficial role of sleep
Why do animals sleep? Why do humans 'waste' a third of their lives sleeping?
Does extra sleep on the weekends repay your sleep debt? No, researchers say
Insufficient sleep and untreated sleep disorders put people at increased risk for metabolic problems, including obesity and diabetes.
Kicking, yelling during sleep? Study finds risk factors for violent sleep disorder
Taking antidepressants for depression, having post-traumatic stress disorder or anxiety diagnosed by a doctor are risk factors for a disruptive and sometimes violent sleep disorder called rapid eye movement (REM) sleep behavior disorder, according to a study published in the Dec.
Sleep health and yoga intervention delivered in low-income communities improves sleep
Pilot study results indicate that a sleep and yoga intervention has promising effects on improving sleep disturbance, sleep-related impairment, and sleep health behaviors.
More Sleep News and Sleep Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

In & Out Of Love
We think of love as a mysterious, unknowable force. Something that happens to us. But what if we could control it? This hour, TED speakers on whether we can decide to fall in — and out of — love. Guests include writer Mandy Len Catron, biological anthropologist Helen Fisher, musician Dessa, One Love CEO Katie Hood, and psychologist Guy Winch.
Now Playing: Science for the People

#543 Give a Nerd a Gift
Yup, you guessed it... it's Science for the People's annual holiday episode that helps you figure out what sciency books and gifts to get that special nerd on your list. Or maybe you're looking to build up your reading list for the holiday break and a geeky Christmas sweater to wear to an upcoming party. Returning are pop-science power-readers John Dupuis and Joanne Manaster to dish on the best science books they read this past year. And Rachelle Saunders and Bethany Brookshire squee in delight over some truly delightful science-themed non-book objects for those whose bookshelves are already full. Since...
Now Playing: Radiolab

An Announcement from Radiolab