The Secrets of Smell Revealed – Different Parts of the Nose Recognize Different Types of Smells

Scientists in Israel report that the distribution of millions of receptors in the nose is not random. They accumulate in small groups that help the brain distinguish good smells from bad ones. Evidence for this theory was gathered in an experiment at the Weizmann Institute of Science involving over 80 people. Volunteers were exposed to odors considered pleasant and unpleasant in many cultures. Electronic probes attached to the volunteers' noses measured the vibrations of nasal neurons. Neuroscientist Noam Sobel's analysis questions the influence of life experience on how people perceive smells. For example, the brain doesn't process all olfactory information. Neurons located in the nose preprocess some of the data. It's as if the nose had its own little brain. The human nose is equipped with what's known as the olfactory epithelium. Analyzing 801 samples, Sobel's team found that some areas of the epithelium are better at detecting odors than others. Furthermore, the researchers also found areas that better distinguish between pleasant and unpleasant aromas.