Life Sciences

Garden of Smells

Many animals depend very heavily on their sense of smell. Our sense of smell has evolved to become a complicated mechanism capable of distinguishing thousands of different scents, although it is a subtle (not always conscious) influence. We rely on smell to to warn us of toxic or hazardous substances, to select foods and explore our environment. We pick up clues about people around us -- not only for identification , but also, subconsciously perhaps, for indications of mood, emotion, and physiological state. Unlike insects, which have smell receptors programmed to detect only one or a few specific odors for the identification of a mate or of a particular predetermined food plant, we have cells that delight or annoy us with near infinite variety of input. In spite of its name, this exhibit is a chemistry exhibit. Chemistry is one subject that is very difficult to deal with in a museum environment. It is either poisonous, wet, or corrosive. This exhibit shows that ordinary people have a wonderful chemistry laboratory in their noses. This laboratory is able to sense subtle differences in the physical structure of molecules. The exhibit also gives us some interesting clues about the functioning of the brain. Smells, more than almost any other sensory input, call forth very rich memories, full of textures, colors, places, and people from past experience. Why is this? The region of the brain into which the olfactory input is channeled is an important memory area in which information from all the senses is integrated and stored. Smell seems to be a powerful key to bring these memories to conscious thought. Further connections in the brain give emotional responses as well as automatic body responses to smell -- such as the reflexive withdrawal from ammonia fumes. It is interesting to note that there is no automatic connection between olfactory region of the brain and that responsible for verbalization. We can distinguish between thousands of smells, but we can not necessarily name them. There seem to be few languages that include nouns (other than the chemical nomenclature) for smells, rather than only adjectives (fruity, woody, like a banana...). With this exhibit, one finds that it is sometimes difficult to identify even familiar smells when they are disembodied from other visual clues.

We'll be adding interesting info and links here. If you have a good one, we need your feedback