Not getting enough sleep doesn't only affect you mentally and physically; it also leaves your romantic partners feeling unappreciated, according to a new study.

Romantic partners often complain about feeling unappreciated, and a new study reveals that poor sleep may play a hidden role.

After studying how sleep habits impact gratitude, researchers found that sleep deprivation can leave people feeling "too tired to say thanks" and can make their partner feel taken for granted.

"Poor sleep may make us more selfish as we prioritize our own needs over our partner's," lead researcher Amie Gordon, a psychologist at the University of California, Berkeley, said in a statement.

Researchers said that the latest findings sheds light on the emotional interdependence of sleep partners and offers compelling evidence that a bad night's sleep leaves people less sensitive to their partner's moods and needs.

Researchers noted that for many people in relationships, nighttime often turns into a battleground of loud snoring, sheet-tugging and space-hogging.

"You may have slept like a baby, but if your partner didn't, you'll probably both end up grouchy," Gordon said.

The study included more than 60 couples between the ages of 18 and 56. In one experiment, participants were asked to keep a diary of their sleep patterns and how the quality of their sleep affected their appreciation of their significant other.

In the other experiment, couples were videotaped while participating in a problem-solving task. Researchers said that those who had a poor night's sleep showed less appreciation for their partner.

The latest findings concluded that poor sleepers had a more difficult time acknowledging their blessings and appreciating their partners.

To make sure poor sleep won't also damage intimate relationships, Gordon suggests that people should always show appreciation and say thanks when their partner does something nice.

Researcher will present their findings Jan. 19 at the annual meeting of the Society for Personality and Social Psychologists in New Orleans.