There’s something about the holiday season that often makes us all a little nostalgic. And it’s not just the result of carefully-crafted marketing by retailers — psychological experts say that wistful feeling has an actual purpose.

Krystine Batcho, a professor of psychology at Le Moyne College in New York, says nostalgia helps us feel connected to one another and can even ease pain during a crisis.

“It seems to help people maintain a constant sense of who they are,” she says. “At a certain point, if there is something traumatic that occurs…that sense of nostalgia helps to link you to your own personal past; it helps you remember who you have been.”

So why are we often so nostalgic during the holiday season? Since our connection to other people helps us define ourselves, Dr. Batcho says nostalgia actually gives us a sense of belonging.

“Everything about the holidays centers around relationships…So in a way, holidays bring together people when they cannot be together. Nostalgia is almost like a psychological substitute for the real thing,” she explains.

It’s also why many people tend to feel so lonely during this time of year. “When you are lonely, it is because you are separate from others in one way or another,” Batcho says. “The holidays are really notorious for making people feel alone, even when they are not physically alone … nostalgia helps someone feel connected again.”

So the next time Christmas songs reduce you to a blubbering mess, just blame it on nostalgia.

More From WGBFAM