A recent study suggests that our noses could be capable of adapting themselves to efficiently inform the brain of the most typical smells in our surroundings. These new findings can help us to gain a better understanding of why and how our noses adapt to these smells, as well as why time and age can decrease the neurons in the nose making our sensitivity to smell weaker.

When molecules drift from items in our surroundings they trigger the receptor neurons in our nose. Mice have up to 10 million receptor neurons in their nose, which are separated into more than 1,000 types. Each type will respond in a different way depending on the molecules detected. Every smell can activate a number of different receptors and every receptor can be activated by a number of smells. So, to fully understand a smell, our brain must be capable of reading the coding of the receptor types and how they are activated.

It is suggested that receptor types are used differently depending on the smell they are exposed to, and that our nose can train itself to inform the brain efficiently as possible about the smells in particular surroundings. Tiberiu Tesileanu, a spokesperson for this recent study explains that the receptor types that are triggered by variable smells carry a lot of information to the brain about regarding this variability and are therefore more abundant in the nose. This appears to be the first time that such coding ideas have been used when looking at the use of these receptor neurons. Further work is needed to look at the types of smells that are typical of our surroundings and how they are detected by our receptor neurons and further experiments could be carried out and compared to help gain a greater understanding of how efficiently neurons carry information to our brains when a new smell is detected.

People who are suffering with a poor or absent sense of smell can help themselves by undertaking ‘smell training’. This is a more modern concept which aims to stimulate the olfactory (smell) neurons in the nose as well as central pathways and also by reactivating smell memories from the brain, with the objective of improving the appreciation of smell. It is a bit like going to the gym to train a muscle except this time it is to improve your sense of smell.

Please visit www.smelltraining.co.uk or www.fifthsense.org.uk for further information about the sense of smell and training.