From Nature: Rats show off ‘stereo smell’
Researchers in India have discovered that a single sniff is enough for a rat to locate the source of an enticing aroma.
Their work shows that rats can effectively smell in ‘stereo’: their two nostrils work independently in much the same way as our ears, with contrasting signals to the brain creating a spatial understanding of sensory information.
The team at the National Centre for Biological Sciences in Bangalore tested the ability of rats to discriminate between smells coming from their left or their right. They trained thirsty rats to drink from a water spout on the corresponding side in response to the odour.
Such is the rodent’s skill that, once trained, they required just 50 milliseconds to decide where the smell was coming from, report Upinder Bhalla and his colleagues in this week’s issue of Science1. The rats selected the correct side with at least 80% accuracy, regardless of the odour presented; the researchers used banana, eucalyptus and rose water in the tests.
When one nostril was covered over, however, the rats lost their ability, showing that they need both nostrils to locate smells, the researchers add. This suggests that the two different nasal passages send contrasting signals to the brain, despite the fact that a rat’s nostrils are a mere 3 millimetres apart.
So it seems to me that the thing to do is design robots that will have not stereo sense but like 5.1 surround sense. I wonder if this could be accomplished simply by adding sensory nodes in a pentaradial fashion on the body of the robot?
have you ever considered that you post way too often for people with lives to keep up?
Hey, it isn’t going anywhere. Thats why there’s all the cataloguing iin the sidebar.
this is the second coolest thing i’ve learned this week.
I have a question. Stereo smell seems to only be sufficient for tracking left/right distinctions. With two independent nostrils, you can triangulate on the source; but on each side of you there is an identical triangle in front and behind you. How would stereo smell distinguish between front and back? I dont know if thast made sense.
my uneducated guess is directional intensity, as things in front of the mouse would be more intense, similar to how ears work…although with sound you’re dealing with vectors and not particles floating through the air. however, the only thing the mouse would have to do is shift its head a little one way or the other, and suddenly it has a lot more information from which it can draw a spatial map of its smelly surroundings.