Memories come through the nose

• April 26, 2024

"And once inside, the perfume went directly to the heart and there decided categorically between inclination and contempt, aversion and attraction, love and hate, who dominated the scents, dominated the hearts of men," he wrote Patrick Suskind in The Perfume , denoting the enormous importance of smells in human life.

When we breathe, a large number of odorous particles suspended in the air ascend through the nose and make contact with the olfactory receptors, which are responsible for sending the signal to the brain so that we are able to perceive odors. Humans can detect up to 10 thousand aromas, but the loss or diminution of this capacity could be a symptom of Alzheimer's disease, which causes memory loss.

Some scientific studies in the United States show that people with Alzheimer's disease do not identify odors such as household gas or menthol. This finding suggests that the loss of olfactory capacity may be an early indicator of a progressive deterioration of brain functions.

Experts from the faculties of Medicine and Chemistry of the UNAM they have started an investigation using "national" aromas, that is, those that are easily recognized by the Mexican population. The purpose is to evaluate the level of olfactory perception of Alzheimer's patients and compare the results with those of their American colleagues.

The initiative is part of a new field of study on the olfactory system, because although it is one of the oldest sensory modalities, there is still much to know about the functions it performs.

Researchers of the School of Medicine They observed that in the lambs, after the birth, the mother sniffs at her offspring and thus keeps the smell in her memory to recognize it among those of her own species. In humans, smell is active from the womb and in the weeks after birth is of great importance. Newborn babies can recognize the smell of their mother even when they are surrounded by other women.

Human beings are also able to store odors in our memory and experience feelings when we perceive them, because the olfactory system is connected to the limbic system, part of the brain where emotions are generated. If in childhood someone came into contact with a pleasing or unpleasant aroma, and in adult life he comes to perceive it again, is able to remember it and relive the past sensation.

Like other mammals, human beings are susceptible to the effects of pheromones, which are released into the environment through sweat and bodily secretions. Scientists define them as chemical signals detected by smell, whose function is to attract the opposite sex.

Each person has a unique smell as a result of the substances that their organism releases to the environment, being fermented by bacteria from the outside, they generate the aroma that distinguishes us from our peers.