According to a study, lack of sleep affects a person's emotional intelligence by giving the brain a hard time distinguishing different facial expressions from other people.

In a research from University of California in Berkeley, authors of the study found out that sleep loss dulls a person's ability to recognize feelings through facial expressions which greatly affects social interactions.

"Recognizing the emotional expressions of someone else changes everything about whether or not you decide to interact with them, and in return, whether they interact you," co-author of the study, Dr. Matthew Walker told Huffington Post.

"Should you lose the ability to read and decode facial emotions, you are placed at a profound social and psychological disadvantage. We know this from conditions such as Autism and Asperger's Syndrome, in which individuals fail to decode emotions, resulting in markedly diminished social and psychological functioning."

Published in the Journal of Neuroscience, 18 young adults were tested on their brain activities and heart rates through an FMRI scanning technique. The experiment detected how respondents react to 70 images of people with different facial expressions, from neutral, friendly, to threatening faces, both with and without a good night's sleep.

The neural link between the heart and the brain is also disconnected when a person lacks sleep.

"It's almost as though, without sleep, the brain... was unable to put emotional experiences into context and produce controlled, appropriate responses," the psychology and neuroscience previously stated. "Emotionally, you're not on a level playing field."

"The real-life implications become clear when you consider professional and societal circumstances where sleep deprivation is common," he added. "Be it doctors and medical staff, military personnel or new parents, the accurate identification and recognition of emotional signals, as well as the need to be guided by them, is utterly critical."

According to Walker, "two thirds of people in developed nations" don't get enough sleep.