Of all of the wondrous feats accomplished by Willy Wonka in his candy factory, the most impressive may have been wedging an entire meal into just one unassuming stick of gum: Upon popping it in your mouth and chewing, you’d first taste tomato soup, then roast beef and baked potato, and finally blueberry pie and cream. This trick seems purely fantastic, but what if a device could really deliver experiences like that? Imagine a gizmo that can bring back the smell and taste of meals long gone, like a beloved grandmother’s drop cookies, the first bite of one’s wedding cake, or the aroma of baked shad from a fishing tradition now seldom practiced. Imagine all of your scents and tastes stored as files alongside music and movies in the digital cloud, ready for re-experience or sharing with friends across social media.
According to one electrical engineer committed to elevating human digital communication, this extension of our digital life is closer to download than you might think. Adrian David Cheok, the founder and director of the Mixed Reality Lab in Singapore, and a professor of pervasive computing at City University London, has long been interested in finding new ways to connect the real world to the virtual world. In 2008 his team developed a remote-controlled hugging pajama, transmitting touch via wifi. Last year, Cheok worked with engineer Nimesha Ranasinghe to produce a “digital lollipop,” a system designed to elicit sensations like sour and sweet by electrically stimulating taste buds. (The effectiveness of the device has not yet been established in a peer-reviewed publication.) Now Cheok is tackling the perception of smell by using magnetic coils to directly stimulate the olfactory bulbs, the seat of scent perception in the brain. Cheok’s goal is to induce smell without the use of chemicals, a feat that has never been done before. And since scent is a prominent part of flavor, a tool that can stimulate scent in the brain could also help recreate better virtual versions of food.
But the task of inducing specific smells, and then flavors, promises to be a hugely difficult one. Of all the human senses, Cheok acknowledges that smell is probably the trickiest to duplicate digitally. The technical challenges Cheok faces show how hard it would be for any would-be Wonka to flip a switch and flood your mind with that perception of grandma’s cookies—and how far off that moment probably is.
“When you’re not tuned to any particular radio station, you hear a kind of noise—audio noise. We actually don’t know what is the equivalent of audio noise for smell.”
Sitting in a big-screen theater with the latest projection and sound equipment, watching a movie shot, edited, and projected with digital gear, you might get the feeling that today’s technology can recreate practically any sensory info. Audio and video, however, are the low-hanging fruit of the sensory world. Sound and light are both types of waves that can be easily generated by machines. Change the shape, size, and frequency of the waves, and you can control what someone sees or hears. But smell involves detecting actual chemicals, with hundreds of different kinds of sensors on the ends of nerve cells. Those sensors can be stimulated in a dizzying number of combinations to transmit particular scents to the olfactory bulbs, and then to other perceptual-interpretation areas of the brain. “You have 450 receptors…and each receptor cell expresses only one type of receptor,” says Richard Doty, director of the Smell and Taste Center of the University of Pennsylvania.
“Any smell is some combination of those various inputs. Banana oil will stimulate a dozen different receptor types, while rose might stimulate some [others] that are unique.” To get the smell of banana right, you’d presumably have to stimulate the olfactory bulbs in a way that corresponds to how the cell receptors have been triggered by banana odorant molecules. It’s a specific combination of inputs, and it has to be stimulated in exactly the right way in order for a person to perceive the banana’s distinctive odor.
For the rest of the story: http://nautil.us/blog/the-long-hard-quest-to-create-digital-smells