Women may actually be superior to men – at least when it comes to their sense of smell, a new study suggests.
Males and females greatly differ in their perceptual evaluation of odours, with women outperforming men on many kinds of smell tests, researchers said.
Sex differences in olfactory detection may play a role in differentiated social behaviours and may be connected to one’s perception of smell, which is naturally linked to associated experiences and emotions.
Thus, women’s olfactory superiority has been suggested to be cognitive or emotional, rather than perceptual.
Researchers used the isotropic fractionator, a fast and reliable technique that measures the absolute number of cells in a given brain structure such as the olfactory bulb, which is the first brain region to receive olfactory information captured by the nostrils.
The team led by Professor Roberto Lent from the Institute of Biomedical Sciences at the Federal University of Rio de Janeiro and the National Institute of Translational Neuroscience, Ministry of Science and Technology in Brazil, found the biological evidence in the brains of men and women that may explain the olfactory difference between genders.
The group examined post-mortem brains from seven men and 11 women who were all over the age of 55 at the time of death.
All individuals were neurologically healthy and none worked in professions requiring exceptional olfactory abilities, such as coffee-tasting or professional cooking.
By calculating the number of cells in the olfactory bulbs of these individuals, the group discovered that women have on average 43 per cent more cells than men in this brain structure.
Counting neurons specifically, the difference reached almost 50 per cent more in women than men.
The question remains whether this higher cell number accounts for the differences in olfactory sensitivity between sexes, researchers said.
“Generally speaking, larger brains with larger numbers of neurons correlate with the functional complexity provided by these brains. Thus, it makes sense to think that more neurons in the female olfactory bulbs would provide women with higher olfactory sensitivity,” said Lent.
The fact that few cells are added to our brains throughout life suggests that women are already born with these extra cells.
Some believe this olfactory ability is essential for reproductive behaviours such as pair bonding and kin recognition.