Next time you're negotiating a new contract, meeting strangers, or trying to get someone to take your side in an argument, it might be a good idea to have some lavender nearby (or at the very least, a lavender-scented candle). 

Researchers from Leiden University in the Netherlands have shown that people inside lavender-scented rooms were more likely to trust complete strangers than those inside peppermint-scented rooms, and rooms with no aroma.  

"Lavender has this effect because of its calming property," cognitive psychologist and researcher Lorenza Colzato told Time Magazine.   

"This hypothesis is supported by the fact that, from an anatomical point of view, the olfactory nerve is connected to the medial prefrontal cortex, a brain region that 'controls' the way we trust others."

Previous studies have shown that our capacity to trust someone can be a "rather volatile" thing, influenced by situational and environmental factors, the researchers wrote in their study, published in Frontiers in Psychology.  

They point to a 1997 study, which showed that pleasant aromas increased prosocial behaviours, such as retrieving a dropped item for someone, or giving them change for paper money. 

The team from Leiden University was interested in seeing whether a person's cognitive control state could be influenced by certain aromas, leading to greater interpersonal trust. 

Cognitive control allows our decision-making and behaviour to be adaptive in certain circumstances, depending on our goals at that moment. It's essentially a function that allows us to strategise to achieve desired results.     

Ninety study participants were paired up and made to play the "trust game" inside a one of three rooms: a lavender-scented room, a peppermint-scented room, and a room with no artificial smell.  

In the trust game, one person (a "trustor") is endowed with a sum of money. They are given the option to keep that money and exit the game, or give some away to a stranger (the "trustee") in the hope that it will lead to a greater return. In the game, money given away is tripled, and then the roles are reversed - the trustee has the option of keeping the money, or returning the favour and sharing the wealth.

In their experiment, participants in the lavender-scented room shared more money than those in the peppermint-scented room and the odourless room.  

"This study is the first to demonstrate that scent can have an impact on interpersonal trust," the researchers wrote

"This observation might have various serious implications for a broad range of situations in which interpersonal trust is an essential element, such as cooperation, bargaining and negotiation, consumer behaviour, and group performance." 

"Smelling the aroma of lavender may help a seller to establish more easily a trusting negotiation to sell a car, or in a grocery store it may induce consumers to spend more money buying products," said lead author Roberta Sellaro, in a press release

Source: Time Magazine