Pamela Rutherford explores:
why the sense of smell prompted to stand on the feet of a paralyzed person,
how does the brain detect and distinguish such countless scents and fragrances,
what happens when the olfactory system fails,
why there is such a strong connection between smells and memory.
☊ The Science of Smell. Link to listening
Try to describe the Bordeaux you were drinking at dinner last night, is it difficult? This is because the smells that give us not only olfactory, but also taste, it is difficult to describe in words.
Recently, scientists have discovered several interesting facts that reveal the secret of this phenomenon. The new study proves the existence of a communication gap between the olfactory and language systems. For example, linguists working with the local population in South Asia have discovered that people describe odors equally poorly. The complexity of the description of fragrances, according to scientists, depends on the language you speak.
Psychologists have found that without special training can correctly identify known, common odors such as coffee or peanut butter, only 50% of the people in the audience. “If someone is difficult during the test to determine the smell and requires visual perception of the object, they get a referral to a neurologist” -says Jay Gottfried, a neurologist from northwestern University (Northwestern University).
Regardless of the reason why it is impossible to describe the smell, it is necessary to take into account how our olfactory system works. Humans have about 400 different types of receptors to detect “odorous” molecules. That’s not much compared to mammals capable of sensing pheromones, but enough, at least in theory, to recognize a trillion different smells — the team of neurologists this year counted.
People who have a subtle sense of smell and the ability to correctly describe the smells and aromas, professionally use your nose, earning a living.
Ordinary English-speaking people in describing the smell in most cases describe its source. For example: orange, smoky, smelly. It seems natural, but it is fundamentally different from how we describe other sensory experiences. Words like” white “and” round ” describe the visual characteristics of an object, not the object itself, which could be a baseball or the moon. It is also possible to describe the audio signal: it can be “shrill”, and from whom it is coming from poultry or kettle — question.
People who are capable of correct olfactory descriptions of smell, work: wine critics, perfume designers and other experts on smells and aromas. With experience, they become experts at describing the smells of familiar objects with a similar smell (for example, Bordeaux has a note of graphite, black currant, camphor?). But not always do expert descriptions help us understand smell, especially when they use abstract terms. Do you understand what the sommelier means when he describes the wine as “strict”, “strong”, “fading”? (Try “blind” tasting).
At the University, D. Gottfried studies people-patients with primary-progressive aphasia, who describe odors particularly poorly. Unlike people with Alzheimer’s, their problem is more about language than memory.
Patients with aphasia are particularly hard-pressed to name common odors, such as roses, onions, gasoline, only 23 percent of them call odors correctly, compared to the 58 percent visual description of the subject. However, when researchers gave the same patients a list of four odor names, about 60% of them identified the items correctly. This suggests that a) their sense of smell is not damaged, and b) they know the right words despite aphasia. Most likely, he reports, we are talking about the connection between the olfactory and linguistic parts of the brain, which is broken.
This study is confirmed by the reaction of the brain: when examined by MRI, people with the greatest deficit of names of odors, as a rule, have damage in the frontal pole. The human brain in the section resembles the shape of a mitten; this place is localized at the tip of the thumb.
D. Gottfried’s latest study, published in the November issue of Neuroscience, also points to this area of the brain as the most important link between smell and language. This time he and his colleagues asked healthy volunteers to identify common odors. At this point, their brain activity was controlled by EEG and MRI. The results pointed to two areas of the brain: the anterior temporal cortex (the same part that was in the previous study with patients with aphasia) and the orbitofrontal cortex, the area immediately behind the eyes that is often involved in decision-making studies (but, like many parts of the brain, probably has several functions, most of which are poorly understood).
Both of these areas of the brain, says D. Gottfried, receive a direct signal from the pear-shaped cortex, a large relay part of the brain for olfactory signals. Indeed, he thinks it may be too direct a connection in the brain between smell and language of description, which causes difficulties in describing the smell. The information the olfactory system passes on to our language centers is crude and relatively unprocessed, like a few notes scribbled on a napkin. The information transmitted from the auditory and visual system is more like a polished object that has gone through several stages, and probably more refined in other sensory areas of the brain.
This neurological communication disorder cannot be universal, says Asifa Majid, a psycholinguist from Radboud University in the Netherlands. Majid worked with two populations in South-East Asia, whose languages have a different relationship with the sense of smell than English.
Manik is spoken by a small group of nomadic hunter-miners in southern Thailand. The smell is an integral part of their lives, from food using medicinal herbs to rituals. “For example, a pig’s badger (Arctonyx collaris) during the dry season is described as smelling caəə(a good flavor often associated with different foods)” – says Majid and her colleague, Evelina Grandson, in the article Cognition. “In the rainy season, however, the badger has an unpleasant smell, like the smell of a lizard.”The manic language, unlike English, has a rich vocabulary of words describing the abstract qualities of smells rather than their source.”
The same applies to juhasova, speaking on the Malay Peninsula. Majid and a colleague, Niklas Burenhult tested in the form of “scratch-n-sniff” with the well-known fragrances, to test the ability to describe the aromas from the ten people who speak cachisca language, and ten speakers of American English. They asked them to name a set of colors. English-speaking participants were very consistent in naming colors – different participants usually used the same color names, but they described different smells. The jahai speakers, unlike the English speakers, were much more consistent with each other in the names of smells. Their description of the smells often coincide with the name of the colors than English speakers.
Like the manic speakers, the jahai speakers used abstract names for scents that reflect the importance of smell in their lives. Goiskoe word cŋəs, for example, roughly translates as “to smell edible, tasty” (like in cooking or sweets), while plʔɛŋ means “to have a bloody smell which attracts tigers” (think milled head proteins in the blood).
For D. Gottfried, the results of the study of A. Majid lead to the conclusion that with the help of abstract names of odors, which can be described several odors, some languages give people the opportunity to cope with the neurological “deficiency” of the name of odors. In other words, the smell is easier to describe with an abstract term that best describes it than to name its original source.
A. Majid has his own interpretation. She suspects that in some cultures, people overcome the deficit in naming smells in another way:”changing perception in the brain.” “For example, for people who speak jahai to be able to talk about what smells, the part of the brain responsible for speech function must connect to the part of the brain responsible for olfactory function.” “I assume that the experience of olfactory language, working in childhood, is very important to use for further successful development.» ITNose expert’s comment:
his material can’t simply and ambiguously perceived by the reader. It is important that the topic of description of smells and aromas excites the minds of scientists and “professional noses” who use this ability in their activities.
Work on this topic continues in different parts of the world by people of different cultures and will be carried out until there is a single language with which to create a single classification of smells and scents.comments powered by HyperComments