Odors are very powerful emotional stimuli, explains Bruce Turetsky, a University of Pennsylvania associate psychiatry professor. In fact, he says, different scents may "have a greater ability to bring up an emotional memory in you than seeing a picture or hearing a voice." So if sense of smell can be linked to emotional memory, can it also be connected to emotional disorders?
It's possible, according to Turetsky. In one study, he measured the size of olfactory bulbs—organs that transport odors to the brain—in 26 patients with schizophrenia, a disease characterized by emotional flatness. On average, the bulb sizes of schizophrenic subjects were 23 percent smaller than those of subjects in a control group. These findings not only concentrate on an area of the brain previously ignored in schizophrenia studies, but, according to Turetsky, they also offer a biological basis to his earlier findings that people suffering from the disease were abnormal in their ability to smell.