In 2004, the Nobel prize in medicine was awarded to Linda Buck and Richard Axel for expanding our knowledge about how our nose works. It is an amazing and complex organ.
Humans can detect over 10,000 different odor molecules. It is important in choosing a mate, identifying our mother, finding food, and avoiding dangers. Every time we inhale through our nose, a whiff of air passes over an area the size of a postage stamp known as the olfactory region.
Receptor neurons on the olfactory bulb contain cilia and binding sites where molecules attach. These molecules or odorants send messages to the brain which result in the perception of smell.
Everyone has their own recognizable smell except identical twins. Trained dogs cannot tell them apart. Women have a keener sense of smell than men and everyone's sense of smell is different. Some people cannot smell a skunk while others can't smell a rose.
Smells evoke memories. And research in Wales has shown that different smells have different effects on the brain. The herb, rosemary, is actually a brain stimulant.
When we loose our sense of smell (called anosmia), we loose our taste for food because smell and taste are so tightly bound. About 80 to 90% of what we call 'taste' is actually smell. We are also put in danger because we cannot detect dangerous situations such as a fire. It curtails our zest for life. Loss of smell affects over 200,000 persons each year.
Loss or reduced ability to smell can be caused by nasal growths or polyps, a head injury, an upper respiratory infection, or an infection of the mucous membranes that line the nasal passage. Some medicines and increasing age have also been blamed for reduced ability to smell.
Research in this area is limited and there are few treatments. For most, recovery is spontaneous but it can take up to a year for smell to return. Surgery to remove polyps may help restore the sensation.. Corticosteroids either in pill or spray form helps many. Anti-allergy medications may be helpful to some.
Unfortunately, many will just have to learn to live with this disability. With as little research about treatment as is available, it is no wonder smell has been called the forgotten sense.
More in-depth information is available online at the following web sites:
American Academy of Otolaryngology−Head and Neck Surgery: Click here
National Institute on Deafness and Other Communication Disorders: Click here