One of the strongest mammalian defense mechanisms is a powerful sense of smell.
What hasn’t really been discovered is how animals are able to distinguish different odors. Two neuroscientists from the Salk Institute and UC San Diego wanted to find out.
They discovered that at least six mammals, from mice to cats, distinguish smells in almost the same way. They looked at the brain’s circuitry for olfaction, or sense of smell, and found that six species had roughly the same size of each of the three components of the olfactory network.
The neuroscientists found that the receptors in the nose transmit signals to a cluster of neurons in front of the brain. That cluster relays signals to a higher functioning odor identifier called the piriform cortex.
Identification of individual odors was linked to the strength and combination of firing neurons in the circuit, kind of like notes on a piano. The neurons reacted at different rates depending on the smell.
The goal for the future is to study various other parts of the brain for other distributed circuits to see if they function the same as the olfactory circuits. They want to see how noise and the variability of odor determines the balance between discrimination and learning about what their brains are telling them.
If we could map out the senses in minute detail, we could create even more advanced artificial facsimiles of the human brain. Robot brains, basically.