For many of us, it's hard to get rid of stuff we've collected over the years. There's good reason for that: For most of human history, many of our possessions have been in short supply. Utensils for cooking and eating. Clothing and materials for shelter. Tools for hunting, gathering, and storing food. Decorations. For the tens of thousands of years human beings lived as hunter-gatherers, these things would have been shared. The average person would have had very few things to call their own. The tendency toward collecting useful things or holding onto stuff you might need runs deep.

These days, of course, most of us would say we probably have more stuff than we need. There's so much of it that it's now something of a status symbol to live a "minimalist" life. It's a lifestyle usually embraced by those who've experienced "too much stuff."

But wherever you are on the continuum, for whatever reasons, you probably have a few things that you just can't bear to give up, no matter what.

People with higher levels of intelligence and imagination, as well as anxiety, tend to find it harder to let things go, according to the book "Stuff: Compulsive Hoarding and the Meaning of Things." If you find discarding or donating things difficult, there's some new research into how you can, in a certain way, trick yourself into de-cluttering, all the while "keeping" things at the same time.

The art of keeping, and yet letting go

In a recent issue of the Journal of Marketing, researchers from several universities looked at what could ease the pain of getting rid of some of your favorite things. Beneath those feelings are the idea that, “These items have some type of meaning that says, ‘this is who I am’ and/or ‘this is who I was,’ so we just don’t want to let this stuff go,” Karen Winterich, associate professor of marketing at Pennsylvania State University, told Futurity.

Winterich was interested in studying the phenomena as she had something of her own she didn't want to throw away: A pair of basketball shorts from middle school. She realized she didn't really want the shorts, but she wanted to hold onto the memory of a great game she played. How could she keep the memory and let go of the object? She realized a picture could be a way to keep the shorts and take up a lot less room.

But would this idea work for others? Winterich and her research team tried out the idea by surveying 797 students in a half-dozen university housing residences. On a donation day that was planned before a holiday break, some of the students were encouraged via an ad campaign to take a picture of their favorite stuff prior donating it. Others saw an advertisement that simply suggested they donate their sentimental things.

They found that people who had the picture option donated from 15 to 35 percent more.

On average, Americans have about 50 items in their homes that are unused (clothing, accessories, electronics or other things). It can be hard to give them up, even if you know that they could be going to someone who would make use of them. Next time you feel that way, figure out what it is you want to remember, take a picture, and let it go.

You might get rid of a few more things. Maybe even more.

Starre Vartan ( @ecochickie ) covers conscious consumption, health and science as she travels the world exploring new cultures and ideas.