Have you ever thought about how our sense of smell has developed over time? How are we able to smell so many different things and be able to distinguish them well? Most of our memories are heavily tied with our sense of smell and it is almost weird that for a long time we didn’t know how we could do that! The discovery of the cells responsible for our sense of smell by Prof. Linda Buck has revolutionized the way we understand the human body! She won the award in the year 2004 along with Prof. Richard Axel.
The journey from psychology to immunology
Prof. Buck’s initial interest was in the field of psychology but sooner than later, an immunology lecture made her change her field of research. She graduated a BS degree in both and then pursued her PhD in Immunology after which she landed up at Columbia University. Here, she met Prof. Richard Alex studying the nervous system of a sea snail through molecular techniques. When she came across a paper on the mysteries of our olfactory (sense of smell) system, she was completely taken back!
She wanted to understand it further because how could we possibly not know anything about our basic senses? The major mystery was that how could we detect over 10,000 different smells? Also, how could identical chemicals generate different perceptions of smell? she spent over 3 years studying olfactory receptors and figured out over 1000 receptors in mice! These were found at the back of their nose where the olfactory epithelium is present. So, what she figured out was that these are protein molecules that bind to an odorant when we smell them. This allows us to recognize different smells! In humans, there are only 350 different types of olfactory receptors though.
The neural-olfactory network
She wanted to know how our brains could be involved in the process of creating an impression of different odors. We have only 350 receptors, so how could we identify more than 10,000 different smells? She soon discovered that one odorant could identify more than two smells and multiple odorants could identify the same smell. This combinatorial code forms a distinguished odorant pattern. That intricate system tends to form multiple permutations that we can smell every day!
Now, how do these smells can be recorded in our memory? All this information would need to be processed to our brain cortex. To date, her work is based on the olfactory system. She is still exploring the various connections between our sense of smell and emotions. Some emotions include attraction, aversion, etc.
Impact of the discovery
The impact of Prof. Linda Buck’s discovery is huge! In terms of the sense of smell, many diseases and disorders are associated with it. Even the recent COVID-19 pandemic has the loss of smell associated as a symptom. But why exactly does our sense of smell get affected when we’re sick? This is something that will need to be answered. Who knows, we might have the answer very soon!
Linda Buck (2020). Retrieved from https://www.nobelprize.org/womenwhochangedscience/stories/linda-buck