People are nose-blind, and you realize it when you happen to sit next to a strong-smelling person in a metro. That person cannot feel the strong smell of his own while that intolerable smell might get to your head or hurt your nose.
How does the nasal cavity perceive smell?
The back of your nasal cavity consists of the unique grouping of cells called the olfactory epithelium. These cells are attached to the olfactory bulb in your brain through the olfactory neurons. There is a receptor cell at the end of each neuron. When microscopic molecules present in the air come in contact with the receptor cells, they attach. This helps transmit an electrical signal, drown the neuron to the brain. The brain then detects it as a perception of a smell.
What causes one to stop smelling their stench?
With each odor molecule attaching a specific protein on the receptor cell, sodium and calcium are carried along with it. This causes the electrical differential across the cell membrane. The pathway it travels is known as the CNG channel (cyclic nucleotide-gated ion channel) that closes due to the rapid influx of calcium. Therefore, the electrical signal sent will no longer be perceived by the brain as smells, and you can hence be nose-blind.
Nose-blind is also known as olfactory fatigue, olfactory habituation, and odor adaptation. Hence, it causes you to stop smelling your stench. For that matter, there are many times that people want to trigger this habituation to let someone smell something.
It is a widespread practice in the fragrance businesses to trigger the olfactory fatigue for people to smell the perfumes and fragrances. A common practice is the smell of coffee beans that triggers the receptor cells to pass the electrical impulse for the brain to detect and perceive the smell. But at large, this practice is as helpful as taking a deep breath of fresh air.
People might stop smelling their stench, but the same receptor cells can be triggered with simple exercises to be aware of once social faux pas. Some of them are the common practices of the fragrance shops that are the coffee beans and a breath of fresh air that will let the electrical signals pass through and make you aware of the smell.