A propos the current thread.
http://www.sciencedaily.com/releases/2011/03/110315093830.htm
A Good Sense of Smell Is More a Product of Training Than Good Genes
ScienceDaily (Mar. 15, 2011) — Do you need to be an expert to have a
good nose? It turns out the answer is yes! Having a good nose is not
something we are born with, but instead just a matter of training.
See Also:
Health & Medicine
This has been demonstrated by Jane Plailly and Jean-Pierre Royet,
researchers at the Laboratoire Neurosciences Sensorielles Comportement
Cognition (CNRS/Université Claude Bernard Lyon 1), and Chantal
Delon-Martin, researcher at the Institut des Neurosciences de Grenoble
(Inserm/Université Joseph Fourier).
The brain imaging experiment that they carried out on professional and
student perfumers reveals, for the first time, that similar regions are
activated during the perception and imagination of odors and that this
activation depends on the subject's level of expertise. This result
shows that, like visual or auditory mental imagery, olfactory imagery
depends on the reactivation of olfactory images within the brain, and
that this capacity develops with experience. This work is published on 8
March 2011 on the website of the journal Human Brain Mapping.
We are all able to visualize our own living room, move about virtually
or mentally hum a catchy tune. But can we recall the smell of toast or a
fig to the point of actually smelling their odor? Olfactory mental
imagery is a much more difficult exercise than visual or auditory mental
imagery and most people say they do not have this capacity. However,
perfumers, olfactory experts used to smelling, evaluating and creating
odors, claim they are capable of smelling an odor even in its absence.
Where does the truth lie?
To answer this question, the researchers used functional Magnetic
Resonance Imaging (fMRI). They compared the spatial organization of the
cerebral activations of students from the Ecole de Parfumerie de
Versailles (ISIPCA) to that of professional perfumers, a rare species
(there are no more than 500 throughout the world, of which some 120 are
in France and Switzerland). While placed in a scanner, the subjects were
asked to mentally conjure up the smell of odorous substances (1), whose
chemical name appeared on a screen.
The results show that in the experts of both groups, olfactory mental
imagery activates the primary olfactory cortex (piriform cortex) a zone
of the brain ordinarily stimulated during perception. This proves that
similar areas are activated during the perception and imagination of
odors. Like visual or auditory mental imagery, olfactory imagery depends
on the reactivation of olfactory images via an internal cognitive
process (our own brain generates this sensation) and not in response to
an odor.
Another finding is that, in perfumers, intense olfactory training
influences the activation level of the neuronal network involved in the
mental imagery of odors. Surprisingly, the greater the level of
expertise, the more the activity of the olfactory and mnesic
(hippocampus) regions is reduced. Thus, when the brain is trained,
"communication" at the neuronal level takes place more easily, rapidly
and efficiently, and the message is more specific, resulting in reduced
activation. This shows that regular training enhances olfactory mental
imagery, which does not stem from an innate faculty.
In this study, the perfumers were able to imagine the odors rapidly,
sometimes instantaneously, whereas the students experienced some
difficulties and needed to concentrate their attention. By easily
reactivating the mnesic representations of odors, perfumers can mentally
compare and combine scents with the aim of creating new fragrances.
These results demonstrate the brain's extraordinary capacity to adapt to
environmental demand and to reorganize itself with experience.
(1) Dihydromyrcenol, aldehyde C11, triplal, alpha-damascone... just some
of the chemical names of the twenty or so odorants selected for the
experiment among the 300 with which student perfumers normally work.
--
((Udhay Shankar N)) ((udhay @ pobox.com)) ((www.digeratus.com))
