We adapt to smells very quickly. Within the space of just a few breaths, we can lose our ability to detect new odors. It’s called olfactory adaptation, and it’s the same reason you can’t smell your own breath, your body odor, or even your perfume after a few minutes. This, cognitive psychologist Pamela Dalton told New York Magazine, may be a good thing.

Every object in our environment gives off scented molecules. When you inhale, the molecules pass through your nostrils and stick to a wall of mucus on the back of your throat. That mucus is home to receptor cells that tell your brain what it is you’ve just sniffed. Our brains watch out for danger. Any change in our surroundings could represent a threat, so the brain focuses on new sights, sounds, feelings—and smells. After a few sniffs, you should know what needs to be dealt with and what’s okay to ignore. Fresh cut flowers? Nice, but not a problem. The smell of burning hair? Maybe to check that out.

Are you worried that your house reeks and nobody’s telling you? You may be able to find out by employing a few tricks of the perfume trade. Since familiarity is the key, you can give your nose a fresh start by leaving the house for a few hours. When you return, you should be able to get a good idea of what everyone else smells.

If that doesn’t work, try jumping around the room for a few minutes. The increased blood flow can briefly improve your sense of smell. Perfumers actually run up and down the stairs between sniffs, Dalton says. (The downside of vigorous exercise is that you may become a little fragrant yourself.

In the end, how the house smells may be less important than how we feel about it; there’s nothing quite like the smell of happiness.