I am glad to see something on smell on the listserv. Olfaction [fancy word
for smelling] is the least understood of the senses. There is an amazing
scarcity of good research in this area, and most of the existing research is
a product of chemists with the various perfume / fragrances manufacturers.
We are not really sure how smell works. Are there only a few receptors which
detect various compoments of an odor and then our minds combine a few inputs
to come up with what we think of as a particular odor..A system analagous to
rods and cones in the eyes.... Or do we have hundreds or thousands or
hundreds of thousands of receptors, each trying to detect a particular
molecule in the air to come up with what we call smell?
Are all odors handled the same? Each of us may be right or left nostril odor
sensitive. Certain smells are handled by the olfactory bulb. It is thought
that certain types of odors trigger the trigeminal nerve to send odor
information directly to the hypothalamus, particularly those odors which
signal imminent danger such as ammonia, skunk, smoke, etc.
Loss of olfactory sensitivity does not have to be uniform within an
individual. There are "notches" where sensing is particularly acute or absent.
I have been in an olfactory test at Graduate Hospital in Philadelphia and am
currently involved with the Univ. of Pennsylvania as a subject in olfactory
testing which is still relatively crude but quite advanced compared to what
has been done before.
I have "notches." I do not smell automobile exhaust, several organic
solvents, or chemicals used by the ladies for permanent waves. Skunk smells
sweet. I particularly have a notch which does not detect xylene. Conrtary to
several articles, I find that my "notches" disappear when ldopa medication
is near peak.
A couple of people I know who have had pallidotomies have regained some of
their sense of smell. A good friend who has Parkinson's and operates a pizza
restaurant has a problem. Prior to his pallidotomy he could not test the
freshness of ingredients by smell, so he relied on his wife for that task.
After his pallidotomy his senses of smell and taste improved, and his
waistline has expanded substantially as a result.
I would like to hear from others who have olfactory "notches."
And here's to long "ons" and short "offs"
WILL JOHNSTON 4049 OAKLAND SCHOOL ROAD
SALISBURY, MD 21804-2716
410-543-0110
Pres A.P.D.A. DelMarVa Chapter
