Scent as a Communication Channel Physically and in VR?
In a study published in Psychological Science, a journal of the Association for Psychological Science, researcher Gün Semin and colleagues from Utrecht University in the Netherlands have expressed interest in the use of pheromones for communication, in all animals including humans. They postulated that scents might actually be playing a role in how we subconsciously communicate, and their results do bear out that possibility. This means there is yet another potential use for scent in virtual environments as a means for increasing the bandwidth of interpersonal communication.
Existing research suggests that emotional expressions are multi-taskers, serving more than one function. Fear signals, for example, not only help to warn others about environmental danger, they are also associated with behaviors that confer a survival advantage through sensory acquisition. Research has shown that taking on a fearful expression (i.e., opening the eyes) leads us to breathe in more through our noses, enhances our perception, and accelerates our eye movements so that we can spot potentially dangerous targets more quickly. Disgust signals, on the other hand, warn others to avoid potentially noxious chemicals and are associated with sensory rejection, causing us to lower our eyebrows and wrinkle our noses.
The researchers sought to build on this basic research, and look at how scents alter the signal patterns. They hypothesized that chemicals in bodily secretions, such as sweat, would activate similar processes in both the sender and receiver, establishing an emotional synchrony of sorts. Specifically, people who inhaled chemosignals associated with fear would themselves make a fear expression and show signs of sensory acquisition, while people who inhaled chemosignals associated with disgust would make an expression of disgust and show signs of sensory rejection.
They tested these hypotheses by collecting sweat excretions from men while they watched either a fear-inducing or a disgust-inducing movie. The men followed a strict protocol to avoid possible contamination. For two days prior to the collection, they were not allowed to smoke, engage in excessive exercise, or consume odorous food or alcohol. They were also instructed to use scent-free personal-care products and detergents provided by the experimenter.
Women were then exposed to the sweat samples while performing a visual search task. Their facial expressions were recorded and their eye movements were tracked as they completed the task.
As the researchers predicted, women who were exposed to chemosignals from fear sweat produced fearful facial expressions, while women who were exposed to chemosignals from disgust sweat produced disgusted facial expressions.
The researchers also found that exposure to fear and disgust sweat altered the womens perceptions during the visual search task and affected their sniffing and eye-scanning behaviors in accordance with either sensory acquisition or sensory rejection. Importantly, the women were not aware of these effects and there was no relationship between the effects observed and how pleasant or intense the women judged the stimuli to be.
These findings are important, Semin and colleagues argue, because they contradict the common assumption that human communication occurs exclusively through language and visual cues.
Indeed, such research is vital for recreating maximum communication ability in virtual environments, where the physial body is not present. Our sole ability to communicate in such environments, is computer mediated,and limited to the means the system understands.
There is also of course the possibility of enhancing certain emotional responses in participants of the VR, based on scents associated with certain features of the environment. Making a dark, dank, scary location a much more intense experience by having the simulation transmit signals to recreate the fear-inducing pheromones to the user's senses.
The more we understand about the role of scent in our perception of the world, the more critical it becomes, to include it within our simulated worlds.