Women Missing Brain's Olfactory Bulb Can Still Smell, Puzzling Scientists
Researchers have discovered a small group of people that seem to defy medical science.
The 29-year-old woman's brain scan was puzzling to say the least: It revealed she was missing brain structures she needed to be able to smell, yet she could sniff out odors even better than the average person.
It turns out, she's not the only one with this mysterious ability, according to a new study published today (Nov. 6) in the journal Neuron. Researchers have discovered a small group of people that seem to defy medical science: They can smell despite lacking "olfactory bulbs," the region in the front of the brain that processes information about smells from the nose. It's not clear how they are able to do this, but the findings suggest that the human brain may have a greater ability to adapt than previously thought.
A group of researchers in Israel made this discovery by chance: They were conducting a different study that involved imaging the brains of patients with a normal sense of smell using magnetic resonance imaging (MRI). But they noticed that one woman seemed to be missing her olfactory bulbs.
The scientists thought this was surprising because the ad for their study had noted participants should have a good sense of smell, and yet, based on her brain scan, the woman shouldn't be able to smell. The researchers thought "maybe she didn't notice" that part of the ad, said senior author Noam Sobel, a professor of neurobiology at the Weizmann Institute of Science in Israel. But when they asked her, she said she had a very good sense of smell. ...
So Sobel and his team asked if they could conduct more scans and tests on her and found that indeed, she had a sense of smell slightly better than the average person. "Our understanding is that odors are essentially mapped on the surface of the bulbs," and the brain somehow reads this map, Sobel told Live Science. If you lack this map, you should also lack the ability to smell, he added.
Deciding to pursue this further, the researchers recruited more people as "controls" to compare with the unusual case. All of these controls were women and all left-handed like the original subject. "Lo and behold," in the ninth scan of a control "we discovered another woman without olfactory bulbs and a perfect sense of smell," Sobel said. At that point, "it started to look like no coincidence." ...
