Our Sense Of Smell Is Underestimated

Even though we do not realize it, our sense of smell is as keen as those of animals, - it seems our ability to follow a scent is not that much different to that of a dog's, say researchers from the University of California Berkeley, USA.You can read about this new study in the journal Nature Neuroscience.Scientists asked 32 blindfolded volunteers, male and female, to follow 10-meter scent trails in a field from one end to the other. The trails were scented with chocolate oil. As well as not being able to see, the volunteers had to wear gloves and earplugs - making them dependent on their sense of smell. Two-thirds of the participants accurately followed the scent trails. The volunteers could be seen crawling on their hands and knees with their noses close to the ground.

To make sure it really was their sense of smell that was guiding them, the scientists made them try to follow a trail again, but this time with their noses plugged (blocked up) - everyone failed.Everyone who succeeded was slower than animals. However, after a bit of practice all the humans improved significantly. The scientists also found that both nostrils are needed in order to follow the directions of a trail - "scent-tracking is aided by inter-nostril comparisons."The scientists say that humans are capable of much more than they realize; adding that with proper training, we should be able to do the work currently just done by animals. The researchers noticed that that as people got better with practice, they sniffed much more frequently and faster.Lead Author, Jess Porter, said that the scientists found people can sniff their way accurately around a spatial context. It seems our two nostrils work together to triangulate a scent path. When asked to follow a scent trail with one nostril plugged, only one third of the volunteers succeeded, compared to two thirds when both nostril are used.As we rely on our other senses, especially our eyesight, we have underestimated just how much we can achieve with our sense of smell.(Source: Nature Neuroscience : University of California Berkeley : January 2007.)