Subtitles section Play video Print subtitles Perfumers can learn to distinguish individual odors in a fragrance made of hundreds of scents. Tea experts have been known to sniff out not just the location where a tea was from, but the season of harvest and whether it was planted by a plum tree. And the New York City Transit Authority once had an employee responsible only for sniffing out gas leaks in the subway system. Can just anyone learn to smell with the sensitivity of those experts? For most of us, what we smell is largely involuntary, whether it's garbage behind a restaurant, the shampoo of the woman leaving an elevator as you enter, or a bakery's fresh-made bread. With a few million olfactory receptors in our noses, we clearly don't lack the ability to smell well. We just might not always pay close enough attention. That's a shame because we may be missing opportunities to make strong emotional connections. Smells are powerfully linked to emotions and can awaken memories of places we've long ago left and people we've loved. But fortunately, it is possible to train our brains to smell better. For example, Helen Keller was able to recognize a person's work, and in her words, distinguish the carpenter from the iron worker, the artist from the mason or the chemist, by a simple inhale. Follow these steps and you too can change the way the world smells to you. First, stick your nose in it. Some animals that are known to be great smellers, like dogs who can sniff out explosives and pigs who can find truffles underground, put their noses right at the place they want to smell. Human noses, meanwhile, are casting around in the middle of the air, giving us an anatomical disadvantage. So bring your nose close to the world around you. The ground, surfaces, objects, the food in your hand. Get close to your dog, your partner, the book you're reading. Not only will your nose be closer to the odor source, but the warmth of your breath will make odors easier to smell. Second, sniff like you mean it. Smelling actually happens way up near the bridge of our noses in a postage stamp-sized square of tissue called the olfactory epithelium. When we sniff, odor molecules are sucked up into our nostrils until they hit this tissue where they combine to our olfactory, or scent, receptors. When we inhale normally, only a little air makes it there. But one or two solid sharp sniffs will ensure that more air gets to your smell receptors. After just a few more sniffs, the receptors, which are best at noticing new smells, turn off temporarily. So you can give your nose a rest and sniff again later. Finally, dwell on the smell. Most smells pass by us with little attention, but simply noticing what you're smelling and by trying to describe it, name it, and locate its source, you can expand your vocabulary of smells. When an odor molecule binds to a scent receptor, it sends an electrical signal from the sensory neurons to our brain's olfactory bulbs. The signal then continues to other areas of the brain, where it's integrated with taste, memory, or emotional information before registering to us as a smell. FMRI (Functional magnetic resonance imaging) research shows that the extra time spent focusing on scent changes the brain of experienced smellers. For them, perceiving and imagining odors becomes more automatic than for non-experts. To get started yourself, take ingredients from your kitchen: spices, vanilla, or fruit, but never anything toxic. Close your eyes and have someone bring them under your nose. Sniff and try to name the source. Over time, you'll begin to appreciate nuances in familiar odors and recognize characteristics of new and unusual smells. The perfumer has practiced these steps enough to become an artist of odor, but even if you never pursue smelling to that degree, the spectacular result of an unspectacular action will change how you sense and experience your days.