Women Really Do Have a Finer Sense of Smell, and Neurology Proves it

If a woman tells her husband that the tuna salad in the fridge smells "a bit off," he probably shouldn't eat it. Chances are she can smell subtle-but-telling odors that he can't, thanks to the fact that her brain is built to boast a superior sense of smell.

That's at least according to a study recently published in the journal PLOS ONE which details how women have more cells in the olfactory bulb - the area of the brain that is dedicated to sense of smell - than men.

When an odor first hits your nose, aroma compounds, called aromatics, strike specialized cells, called olfactory sensory neurons, which are found in a small patch of tissue high inside the nose. These cells react to the aromatics, and send varied signals directly to the brain.

The first part of the brain that receives these signals is the olfactory bulb, which serves as the final translator of these signals - where a person's ability to discriminate between various odors is truly determined.

It has been suggested that the complexity and size of an olfactory bulb can say a lot about a person's odor sleuthing abilities, where interpreting odor signals with just a few olfactory neurons is basically the equivalent of trying to understand a Roman with just a few days of Italian 101 under your belt.

And compared to women, men's olfactory bulbs might as well start carrying around an Italian-English dictionary. That's because in an assessment of 11 women and seven men, researchers found that  women on average have a whopping 43 percent more neurons in the olfactory bulb than men.

Research lead, Roberto Lent, at Rio's Federal University, admitted in a statement that it has never been proven that more olfactory neurons means a finer sense of smell.

However, "generally speaking, larger brains with larger numbers of neurons correlate with the functional complexity provided by these brains," he explained. "Thus, it makes sense to think that more neurons in the female olfactory bulbs would provide women with higher olfactory sensitivity."

The researcher and his team now hope to explore whether it is nature or nurture that encourage women to develop such a more complex bulb, compared to men, and why exactly this would be necessary.