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- Les
biographies de
neurologues
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- ROBERT WHYTT, the predecessor of William
Cullen in the chair of medicine at Edinburgh, is
less well known, but his contributions to
clinical medicine and particularly to the
pathogenesis of reflex action place him firmly
among the foremost physicians of Edinburgh in
the 18th century. His clear description of
tuberculosis meningitis, his explanation of the
sentient (sensitivity) principle in involuntary
action, and the significance of emotions in the
natural history of organic diseases easily
offset his mistaken emphasis on the value of
lime-water in the treatment of urinary tract
concretions. Whytt (pronounced White) was born
four years after Cullen. His father, a member of
the Scottish bar and proprietor of the estate of
Bennochie, died six months before Robert was
born. His mother died when he was six years old.
He must have been blessed with wise and good
guardians who made it possible for him to obtain
an excellent education. Following graduation
with a master of arts degree from St. Andrews in
1730, he spent the next four years studying
medicine at Edinburgh, concentrating in anatomy
under Monro Primus. He then went to London,
became a pupil of Cheselden, and walked the
wards of the city hospitals. After London, he
made his pilgrimage to the Continent, spent time
in Paris at La Charité and Hôtel
Dieu, and in Leyden audited the lectures of
Albinus, who was in his midmaturity and those of
Boerhaave, who was in his retiring years.
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- Whytt took the degree of medicine at Rheims
in 1736. Rheims, though seldom mentioned among
the great schools of France, enjoyed a short
term of popularity with the physicians of
Edinburgh, several of whom graduated MD from
this school in the 18th century. Whytt received
a second MD degree from St. Andrews and became a
licentiate of the Royal College of Physicians of
Edinburgh. He presented both degrees. for
fellowship in the College in 1738 and
immediately began practice. At the age of 33, he
was appointed professor of the theory of
medicine at Edinburgh and held the chair until
his death in 1766. Cullen did not succeed to the
post until seven years later. In 1752, Whytt was
elected a fellow of the Royal Society of London
and in 1761 was appointed physician to the king
of Scotland.
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- Before succeeding to the chair in Edinburgh,
Whytt published a treatise on the use of alicant
soap and lime-water in the treatment of urinary
tract calculi. Since bladder stones were
encountered frequently in the practice of his
time, effective measures for preventing or
dissolving the concretions appealed greatly.
Whytt, by his chemical studies, exploited the
possibilities of the secret formula developed by
Mrs. Joanna Stephens, which had been purchased
by the British government and which consisted of
calcined egg-shells, soap, and aromatic bitters.
The therapeutic value of limewater was
attributed to a peculiar property of the
solvent, when used as a bladder irrigant, rather
than to its alkaline reaction. It is possible
that large quantities of an alkaline fluid might
have caused some inhibition of formation of uric
acid stones; whereas a high fluid intake in
persons who had previously been on a low fluid
intake might have brought slight benefit.
Probably the most enduring consequence of the
limewater misconception was the attention given
to the subject by Joseph Black, who, in
searching for a solvent for stones a decade
later, discovered "fixed air" or carbon
dioxide.
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- In the chair of medicine, Whytt devoted much
time to physiological investigation. The Essay
on the Vital and Other Involuntary Motions of
Animals is primarily concerned with reflex
action, his best contribution to scientific
medicine. It was published in 1751 and presented
the concept of a sentient principle which
received the afferent stimulus and dispatched
the efferent response in involuntary motions.
Descartes, Robert Boyle, and Stephen Hales had
previously discussed reflex action, which
knowledge was extended by Whytt, who
demonstrated in physiological experiments that
only a small segment of the spinal cord was
necessary for reflex action. Reflex function was
shown to depend neither upon the integrity of
the brain nor upon the intact and entire spinal
cord. This physiological explanation was quite
contrary to the rational, conscious soul concept
advanced by Stahl. Whytt also localized the
reflex action of the pupil (Whytt's reflex),
noting the afferent pathway in the optic nerve
and the efferent pathway in the third nerve.
Also, he suggested that persistent dilatation of
the pupil could be produced by compression of
the optic thalamus. «From this case it
seems probable that the dilatation of the pupil
soon after the coming on of the coma, was owing
to the compression of the thalmami nervorum
opticorum, by the water collected in the brain,
which rendered the retina insensible of the
stimulus of light».
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- This presentation of sensibility and
irritability, which could be demonstrated by a
number of involuntary actions, brought a rebuke
from von Haller, who contended that irritability
of a muscle was independent of nervous influence
and sensation. Whytt remained firm in his
conviction that muscular contraction was under
nervous control. One of the best illustrations
of the sentient principle is the rhythm of the
heart.
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- «How far the mind is really
concerned in the motion of the heart, may easily
appear from what has been already in the
preceding Sections; where, if I mistake not, it
has been shewn beyond doubt, that the
contraction of the heart is owing to the
returning venous blood acting as a stimulus upon
it; and made highly probable, both from reason
and analogy, that a stimulus excites our muscles
into motion, only as they are animated by a
sentient principle. Whence it must follow, that
the alternate contractions of the heart are in
no other sense owing to the irritation of the
returning blood, than as the mind or sentient
principle is, by this, excited to increase the
action of the nerves upon its fibres.
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- This doctrine of the alternate motion of
the heart as proceeding from the power of the
mind, excited into action by the stimulus of the
returning venous blood admitted into its
cavities, is greatly strengthened by the account
we have given of the alternate motions of
respiration, of the contractions of the muscles
of the internal ear and of the pupil. These we
have clearly shewn to proceed from the mind, as
affected by a stimulus, and to be altogether
inexplicable upon principles merely
mechanical.
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- The mind, therefore, in carrying on the
vital and other involuntary motions, does not
act as a rational, but as a sentient principle;
which, without reasoning upon the matter, is as
certainly determined by an ungrateful sensation
or stimulus, affecting the organs, to exert its
power, in bringing about these motions, as is a
balance, while, from mechanical laws, it
preponderates on that side where the greatest
weight prevails».
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- Whytt's neurophysiological discussions were
complemented by clinical observations on
nervousness, hypochondriasis, and hysteria. The
extent that emotional factors penetrate into or
become an integral factor in the pathogenesis of
clinical disorders, not usually classified
primarily nervous, is exemplary and modern.
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- «The disorders which are the subject
of the following Observations, have been treated
of by authors, tinder the names of Flatulent,
Spasmodic. Hypochrondriac or Hysteric. Of late,
they have also got the name of NERVOUS; which
appellation having been commonly given to many
symptoms seemingly different, and very obscure
in their nature, has often made it be said that
Physicians have bestowed the character of
nervous on all those disorders whose nature and
causes they were ignorant of. To wipe off this
reproach, and, at the same time, to throw some
light on nervous, hypochrondriac and hysteric
complaints, is the design of the following
Observations; which are also intended to shew,
how far the principles laid down in my Essay on
the vital and other involuntary Motions of
Animals, may be of use in explaining the nature
of several diseases, and consequently, in
leading to the most proper method of
cure.
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- Since, in almost every disease, the
nerves suffer more or less, and there are very
few disorders which may not in a large sense be
called nervous, it might be thought that a
treatise on nervous diseases should comprehend
almost all the complaints to which the human
body is liable».
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- The monograph on tuberculosis meningitis,
published posthumously by his son with the title
Observations on the Dropsy in the Brain, has
been adjudged his most important
clinicopathological study. The natural history
of the disease was divided into three stages
according to the pulse rate, alternating from
rapid to slow to rapid.
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- «Children who have water in the
ventricles of the brain begin to have many of
the following symptoms, four, five, or six
weeks, and in some cases much longer, before
their death.
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- At first they lose their appetite and
spirits; they look pale, and fall away in flesh;
they have always a quick pulse, and some degree
of fever.
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- While the feverishness continues or
increases, they lose their appetite more and
more; ... They are thirsty, and frequently vomit
once or twice in a day, or once in two days.
They complain of a pain in the crown of their
head, or in the forehead above their eyes . . .
. Their spirits being low, they incline mostly
to lie in bed, aitho' they are often more
disposed to watching than to sleep. They cannot
easily bear the light, and complain when a
candle is brought before their eyes.
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- I date the beginning of the second stage
from the time the pulse, from being quick but
regular, becomes slow and irregular. This
sometimes happens about three weeks, often a
fortnight or less, before the death of the
patient.
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- During the second stage, most of the
symptoms mentioned in the first continue. The
sick are then unable to sit up, tho' generally
they sleep little, till towards the end of this
period, when they begin to grow drowsy. They
moan heavily, yet cannot tell what ails them.
Their eyes are often turned towards their nose,
or they squint outwards, and sometimes they
complain of seeing objects double. Some, towards
the end of this stage, grow delirious, and cry
out in a wild manner, as if they were much
frightened.
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- In the third stage, the patient, who
before was little disposed to sleep, becomes
then drowsy and comatose. When roused, he utters
only a fev, incoherent words, and appears to be
insensible. The beginning of the coma is
uncertain; it is often about the end of the
second stage before the pulse grows quicker for
the second time.
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- Frequently one eye-lid loses its motion,
and afterwards the other becomes also
paralytic.
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- In this stage, the patients are sometimes
observed to be constantly raising one of their
hands to their head; and are generally troubled
with convulsions of the muscles of the arms,
legs, or face, as well as with a subsultus
tendinum.
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- Upon opening the heads of ten of those
patients from whom I have collected the symptoms
above mentioned, I found in all of them a clear
thin fluid in the anterior ventricles of the
brain, immediately below the corpus callosum.
There was frequently the same kind of liquor in
the third and fourth ventricles; but whether
this is always the case, I cannot say, as I had
not attended sufficiently to this
circumstance».
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- 1. Seller, W.: Memoir of the Life and
Writings of Ifobert Whytt, M.D., Trans Roy Soc
Edinburgh 23:99131, 1864.
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- 2. Whytt, R.: An Essay on the Vital and
Other Involuntary Motions of Animals, 2nd ed,
Edinburgh: J. Balfour, 1763.
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- 3. Whytt, R.: The Works of Robert Whgtt,
M.D., published by his son, Edinburgh: j.
Balfour, 1768.
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- 4. Whytt, R.: Observations on the Nature,
Causes, and Cure of Those Disorders Which Have
Been Commonly Called Nervous, Hypochrondiac, or
Hysteric, Edinburgh: J. Balfour, 1765.
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- 5. Whytt, R.: Observations on the Dropsy in
the Brain, Edinburgh: J. Balfour, 1768
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- Robert Whytt was physician to King George
III in Scotland from 1761.
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- Notable Publications:
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- Essay on the Vital and Other Involuntary
Motions of Animals, (1751)
- An Essay on the Virtue of Lime-Water in the
Cure of the Stone, (1752)
- Physiological Essays, (1755)
- Review of the Controversy Concerning the
Sensibility and Moving Power of the Parts of Men
and Other Animals, (1761)
- Observations on the Nature, Causes and Cure
of Those Disorders Which Have Been Commonly
Called Nervous, Hypochondriac or Hysteric,
(1767)
- Observations on Dropsy of the Brain, (
1768)
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