More evidence that the human ability to take in information molecules, sometimes known as pheromones, comes from a study by Wen Li of the Cognitive Neurology and Alzheimer's Disease Center at Northwestern's Feinberg School of Medicine.
The study found that smells below the level of conscious discrimination influenced people's feelings about others. The researchers had subjects sniff three vials, containing a lemon scent, the scent of sweat and a neutral scent. Afterwards, they were shown photos of neutral faces and asked to rate them from unlikeable to extremely likable.
Those who could detect the smells tended not to be biased by them, but those who could not detect the smells tended, I suppose, to rate faces as less likable after inhaling the unpleasant odor.
According to the article,
The acute sensitivity of human olfaction tends to be underappreciated. "In general, people tend to be dismissive of human olfaction and discount the role that smell plays in our everyday life," said Gottfried. "Our study offers direct evidence that human social behavior is under the influence of miniscule amounts of odor, at concentrations too low to be consciously perceived, indicating that the human sense of smell is much keener than commonly thought."
If we're able to process molecules taken in through our noses -- possibly through the vomeronasal organ -- it means that we might be influenced by molecules of oxytocin released by another person.
Here's a link to the abstract of the study, Subliminal Smells Can Guide Social Preferences.