Fear Smells: Scary Memories Make Odors More Pungent
Fear smells. Because terror triggers a heightened sense of smell, the same emotion can return whenever our noses detect aromas associated with scary memories.
Scientists at Rutgers University said the latest findings could have implications for treating post-traumatic stress disorder, which sensory information can trigger an attack.
The latest study involved mice. Researchers used electric shocks to implant fear memories associated with certain smells in the laboratory animals.
The findings revealed that the neurons in the noses of laboratory mice became four times as active when they detected threatening odors. Researchers explained that the animals' receptors reacted more strongly before the odor message was sent to the brain.
Researchers said the latest findings suggest that our senses act as a "warning signal" for dangerous situations.
"What is surprising is that we tend to think of learning as something that only happens deep in the brain after conscious awareness," John McGann, associate professor of behavioral and systems neuroscience in the Department of Psychology, said in a news release. "But now we see how the nervous system can become especially sensitive to threatening stimuli and that fear-learning can affect the signals passing from sensory organs to the brain."
Researchers have long assumed that our organs like our eyes, nose and ears are detectors that send sensory information to our brains, which decode what the messages mean.
"In the old model the eye is like a camera, the ear like a microphone, the nose like a chemistry lab, and the job of the brain is to analyze this information," McGann said, according to the Daily Mail.
Researchers said the next step is the see if the hypersensitivity to certain smells can be reversed. Researchers said that this could help lead to a better understanding of fear learning and lead to novel treatments for PTSD and other anxiety disorders.