Salon has a neat interview with Dr. Alan Hirsch, founder and neurological director of the Smell & Taste Treatment and Research Foundation in Chicago. He argues here that the sense of smell immediately leads us to value judgment than the other senses are and then explains how our moms influence our tastes:
And what’s the relationship between nostalgia and smell?
The quickest way to a change of mood or behavior, quicker than any of the other sensory modalities, is smell. When you smell something you immediately decide whether you like it or you don’t like it, and then you figure out what it is, whether it’s rose or lilac–which is totally different than all the other sensory spheres. When you see a picture of a cow or a horse, you identify it, and then you decide if you like it or not. With smells it’s the exact opposite. It’s a pure affective or emotional sense.
Anatomically, it’s hardwired. The part of the brain that processes smells is actually right there where the emotions are, and that’s because odors were important for the survival of the species — to be able to detect if there were any particular pheromones present, or if a lion was about to attack you. It was important for an infant’s survival to be able to smell the mother. All these things were evolutionarily important, so it makes sense why smell would continue to be so emotional.
And how do we learn to like what we like?
Part of it has to do with past experience. If your mother eats Chinese food when she’s pregnant, you’re more likely to like Chinese food later on. If your mother eats carrots when she’s nursing you, you’re more likely to like carrots. There’s this phenomenon of “neophobia,” when you’re fearful of new foods. The more you’re exposed to a food, the more you like it, and if you’re exposed at a very early age, you like it that much more.
So part of it is this exposure, and part of it has to do with your genetics. We all taste differently. Some people can’t taste the bitter taste that’s found in green leafy vegetables, and they tend to like vegetables more. All of these things will impact your preferences. And superimposed on that are cultural expectations– seeing commercials for “Trix are for kids”– that make you more oriented towards one food over another.
We’ve also looked at geographic distributions of olfactory evoked nostalgia. While baked goods are number one, people from the East coast describe the smell of flowers as making them nostalgic for childhood. In the South it was the smell of fresh air, and in the Midwest it was the smell of farm animals. On the West coast it was the smell of meat cooking or meat barbequing. It also depends on when you were born. For people born from 1900 to 1930, natural smells made them nostalgic for their childhood—trees, horses, hay, pine, that sort of thing. People born from 1930 to 1980 were more likely to describe artificial smells that make them nostalgic for childhood—Playdoh, Pez, Sweet Tarts, Vapo rub, jet fuel.
Read his answers to six more questions along these lines here.