There are plenty of sweet perks to driving a new car, from fiddling with the fancy features to watching your coworkers drool as you pull into the office parking lot. But the very best thing about being in a fresh-out-the-factory ride might be the most basic: breathing in that unmistakable new-car smell.

Just why do we go crazy for certain aromas like car scents—or these 7 Smells That Improve Your Day?

“Odors really reflect experiences,” explains Robert Henkin, cognitive neurologist and director of the Washington, D.C. Taste and Smell Clinic. “The association of an odor with a memory becomes very, very potent in terms of either pleasantness and arousal or unpleasantness and disapproval.” 

When you take a whiff of an aroma, your olfactory nerves deliver this sensory information from your nose to the limbic system, the area of your brain that deals with memories and processes emotions. How can we make scents of this? (Sorry, we had to.) 

Keep in mind that positive aspects of a memory can make an odor smell better to you, Henkin says. For instance, owning a new car would make you think of wealth and achievement, so you link the smell with those feelings.

Studies back it up: At Brown University, women played a computer game in a room that smelled like dirt, rain, and buttered popcorn. If participants enjoyed the activity, they were more likely to prefer the concoction they smelled. But participants who played a version of the game that was rigged to make them lose rated the smell poorly. 

Related odors work the same way. If you had a pleasant experience that involved similar components of the scent you sniffed, those ingredients may evoke related emotions. For example, you may reminisce back to a great summer on the lake riding motorboats each time you smell gasoline. (Feeling nostalgia also makes you less lonely and more optimistic. Check out Your 3-Minute Mood Booster.) 

Why do strong smells like gas, markers, or a campfire evoke such passionate reactions?

“Most people don’t think about smell very much at all,” says Henkin. “So we generally respond to those scents that are relatively vigorous, powerful, or robust because they are strong enough to break through from the obvious lack of smell in the environment. They are perceived as being special.” 

There are always limits to our approval, Henkin adds. “While smelling charcoal at a level that is perceptible without being overwhelming is considered pleasant, if it’s too smoky, it becomes unbearable and stimulates pain receptors. There are pluses and minuses here with any kind of odor, intensity, and character.”

Evolution may also have a hand in making you feel scentimental. (Last one, we promise.) 

Ever take a whiff of a baby’s head and wonder why the hell you love it so much? Research at the University of Pennsylvania showed the newborn smell increased brain activity in areas linked with good feelings, or neostriate areas. Study authors attributed this feeling—similar to that of a drug addict finally getting a fix—to nature’s way of providing a bond between parent and child.