Research on smell – what scientists call olfaction – is discussed in the December issue of the Reader’s Digest magazine in an article by Paula Dranov. She explains how smells are composed of molecules that bind to our smell receptors located at the top of the nasal cavity. According to Nobel Prize-winner Linda Buck “A slight change in the chemistry of an orange scent and you get something that smells like sweaty socks”.
Linda Buck and Richard Axel won the 2004 Nobel Prize for medicine for identifying the approximately 1000 genes (3 per cent of the human genome) that code for the hundreds of smell receptors.
The article also mentions research looking at how smells could be used to help obese people eat less, based on the idea that satiety has less to do with feeling full and more to do with our senses of smell and taste feeling satisfied.
Brain damage can affect our sense of smell with unwelcome consequences. Dranov describes the case of Melissa Wittenborn who lost her sense of smell after an ice skating accident. A hit on her head caused her brain to shudder inside the skull, severing a nerve in the olfactory area. Wittenborn said “I’m missing out on so much, such as smelling my kids and husband when they get out of the shower”.
Losing one’s sense of smell can also be a sign of neurological illnesses like Alzheimer’s, Parkinson’s or Multiple Sclerosis.
Of course, smell is intimately related to memory. There’s a wealth of research showing that smell can aid recall, but there’s also more recent research showing that irrelevant smells can hinder memory.
Link to research on smell and dieting (and lots of other smell research)
Link to research on human pheromones
Link to research on irrelevant smells
Link to research suggesting smelling nice could help in interviews
Link to research on whether humans can sense the direction of smell
Link (item 2) to the vibration theory of smell