The Nose Knows: Combining Scents with Virtual Reality to Combat PTSD Virtual reality programs try to make you feel like you’re there (wherever there is) by imitating the sights and sounds of an experience as accurately as possible.

But what about your other senses, like smell? Many people believe that smell holds a particularly vivid connection to memory and experience. You’ve probably felt it–you go into a room and all of a sudden a smell hits you that throws you back to another time and place. Science writer Jonah Lehrer elucidates:

Why is smell so sentimental? One possibility, which is supported by this recent experiment, is that the olfactory cortex has a direct neural link to the hippocampus. In contrast, all of our other senses (sight, touch and hearing) are first processed somewhere else – they go to the thalamus – and only then make their way to our memory center. This helps explain why we’re so dependent on metaphors to describe taste and smell. We always describe foods by comparing them to something else, which we’ve tasted before. (“These madeleines taste just like my grandmother’s madeleines!” Or: “These madeleines taste like the inside of a lemon poppy seed cake!”) In contrast, we have a rich language of adjectives to describe what we see and hear, which allows us to define the sensory stimulus in lucid detail. As a result, we don’t have to lean so heavily on simile and comparison.

Given the importance of smell to memory, a team of scientists at the University of Central Florida has decided to add smells to virtual-reality therapy for Iraq and Afghanistan war vets suffering from post-traumatic stress disorder (PTSD). This type of therapy helps the vet relive their traumatic experience(s) gradually while engaging in talk therapy, so that they can overcome their fear and move past the experience. (As the lead scientist on the study puts it, “If you’re afraid of a dog, how do you get over it? By being around a dog.”) By adding smells associated with the wartime environment–everything from burned rubber to spices to body odor–the scientists hope to make the virtual reality environment more realistic–a better representation of the soldier’s traumatic experience. Their belief is that the more realistic the virtual reality program, the more helpful it will be as a therapeutic aid for PTSD.

Dedicated research on innovative PTSD therapies like this is extremely important in this day and age, considering it’s been estimated that hundreds of thousands of Iraq and Afghanistan veterans–between 20 and 35% of returning soldiers–suffer from the disorder.

If you’d like to read more about the study, check out this article in the Orlando Sentinel.