Scientists uncover new clues about how the brain smells
A team of neuroscientists from Cold Spring Harbor Laboratory (CSHL) have discovered that, unlike prior studies that showed predictable links between molecular properties of odors and early stage activity in the olfactory system, these correlations “held little predictive power when new odor pairs or shuffled properties were tested.”
These new findings are published in Nature Neuroscience.
“We don’t really know what the brain is looking for [when it comes to smell], and we don’t know what physical or chemical features, if any, the brain extracts,” said Florin Albeanu from CSHL.
It’s understood that odor particles first enter via the nasal cavity, where they are bound to odorant receptors expressed by the olfactory receptor neurons within the sensory tissue. Then, the olfactory bulb processes information sent up from the receptors.
It then sends this information to processing areas in the brain, including the cerebral cortex, where the olfactory output messages are analyzed and broadcasted throughout the brain, eventually being conveyed back to the bulb.
“Rich feedback makes the olfactory system somewhat different from the visual system,” Alexei Koulakov said. “Olfactory experience is very subjective, perception of smells actually depends on the context, and on an individual’s prior experience.”
Therefore, Albeanu and Koulakov believe it’s probably that the entry-level of olfactory inputs and the further processed bulb outputs pick up on the different aspects of smell.
These new results provide an opportunity to build a more comprehensive computational model for the odor space that captures the differences in informational relevance for scent features across the landscape of olfactory processing.
Image Credit: Shutterstock/Yuganov Konstantin