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1901 2012
Prize category:
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The Nobel Prize in Physiology or Medicine 1914
Robert Bárány
Presentation
The following account of Bárány's work was given by Professor G. Holmgren, Member of the Staff of Professors at the Caroline Institute*
Robert Bárány dedicated the most
important part of his scientific research to a study of the inner
ear, particularly to that part of it which is innervated by the
nervus vestibularis and is, therefore, known as the vestibular
apparatus.
In the early 19th century Flourens had already proved by
experiment that by stimulating the semi-circular canals of the
inner ear certain rhythmical eye movements (called nystagmus)
could be caused and Purkinje showed that in human beings vertigo
was induced by rotation. Ménière was the first to prove
that diseases of the inner ear can produce giddiness. Later, a
number of physiologists, especially Breuer and Ewald, studied the
physiology of the inner ear and increased our knowledge of it in
a high degree. Otologists also made daily observations in this
field without, however, appreciating their significance and
adapting them to the service of otology.
After Bárány, in May 1905, had communicated his
observations on caloric nystagmus to the Austrian
Otological Society, there followed during the next ten years a
tremendous, almost revolutionary development of otology, in which
Bárány's work was both the foundation and the central
theme; many other research workers also contributed, in
particular the younger generation of otologists in Vienna
(Alexander, Neumann, Ruttin and others).
The starting-point of the work appeared, at first, to be quite
simple. For a long time otologists had been aware that the
syringing of a patient's ears often caused dizziness - some
doctors had even observed nystagmus. But it was not known by what
agency this came about or which organ released the phenomenon.
Bárány made a systematic study of the question and
found that syringing of the ear regularly produced nystagmus of a
certain type. This nystagmus was connected with a feeling of
giddiness. The explanation came to him quite by chance. A patient
whose ears he was syringing said to him one day that he
experienced a strong sensation of vertigo when the syringing
water was too cold. Bárány then used very warm fluid in
the syringe and the patient again complained of severe vertigo.
Bárány noted the appearance of nystagmus here too, but
its direction was the exact opposite to the one previously
observed. The explanation was now clear. The decisive factor was
the temperature of the syringing fluid and it was soon also clear
that the phenomenon, the so-called caloric reaction,
proceeded from the semi-circular canals, in which the endolymph
increases in specific gravity with cooling, showing a tendency to
sink, whereas with warming the specific gravity decreases and the
fluid shows a tendency to rise. The flux, or tendency to flux,
which then appears in the endolymph of the semi-circular canals
produces the reaction.
As a corollary of this simple explanation it then followed that a
series of earlier hypotheses could be ruled out. The essential
facts are simply whether the labyrinth is cooled or warmed and
what the position of the head is when the process takes place.
The caloric reaction for the first time provided otology with a
method of investigation of the excitability of the vestibular
apparatus which can be used in practically all cases. If the
reaction is positive, then the canals are excitable, i.e. not
totally destroyed, if it is negative then they are destroyed -
with a few, easily checked exceptions. This very simply obtained
reaction has become basic for our understanding of, and therefore
for our therapeutic handling of, a number of labyrinth diseases -
in particular those of an inflammatory nature. The mortality rate
in a certain group of these, which used to be reckoned at 30-50%
has now been reduced to a minimum - according to some statistics
= ± 0, and this is mainly thanks to the caloric reaction and
the labyrinth surgical methods which have been based upon
it.
Bárány also studied systematically the other vestibular
reactions. He provided an explanation for the vestibular
phenomena occurring after rotation which was in sharp contrast to
what had been thought before and established the clinical and
physiological importance of the so-called rotatory reaction. By
means of the so-called fistula test he made the «pneumatic
hammer» of the physiologist Ewald available for clinical use
and he gave the galvanic reaction the secondary place which it
now occupies.
He also studied the remaining phenomena of the vestibular
syndrome, both the subjective and the objective ones, and
systematized them. Here he was chiefly concerned with developing
the question of the so-called vestibular reaction movements.
First of all he established that vestibular disturbances of
equilibrium, which were already known, occur in a regular manner,
in a certain relationship to the existing nystagmus, so that
change of position, or tendency to change of position, always
occurs in the same plane but in an opposite direction to the
existing nystagmus. From this follows the interesting and
clinically extraordinarily important fact that existing
vestibular imbalance changes direction with an alteration in the
head position. These imbalances, which may stem from the muscular
apparatus of the trunk, correspond with other analogous phenomena
in all the other muscles which are directed by the will. With an
appropriate series of experiments it can be shown how each
extremity, or part of an extremity, deviates from a certain
position, or tends to deviate, in the same plane but in an
opposite direction to the nystagmus caused, or already present.
This previously quite unknown phenomenon has become, through
Bárány's so-called pointing test, an integral part of
the examination methods of ear and nerve specialists.
Attempts to explain the phenomena drew Bárány in a new
and promising direction leading to important investigations into
the function of the cerebellum. Bárány thinks that
constant impulses are going out from the cortex of the cerebellum
to all the muscles controlled by the will which are thus held in
a constant, and under normal circumstances, uniform state of
tension (tonus). This tonus is influenced by the stimulation of
the vestibular apparatus in the regular manner already indicated.
If one applies the simple test ( Bárány's so-called
pointing test) of raising the outstretched arm from a downward
position upwards opposite a suitably situated, fixed object, e.g.
a graduated disc (Boivie), it will be found that with repeated
attempts every normal individual reaches approximately the same
spot each time with either open or closed eyes. If the same test
is repeated after stimulation of the vestibular apparatus, i.e.
after syringing an ear with cold or warm water, the subject will
point wrongly with closed eyes and always in the same way, that
is to say, in the same plane in which the nystagmus occurs, but
in an opposite direction. The reaction will be the same,
mutatis mutandis, if the arm is moved in the horizontal
plane or if the test is made with the leg, forearm, lower leg,
trunk, head, etc. Bárány has illustrated this in an
excellent manner. Let us imagine a horse walking and being led by
two stretched reins. The horse can be led out of its direct path
either by a stronger pull on one rein or by a loosening of the
other. In Bárány's pointing test the cortex of the
cerebrum represents the active force - the horse - while the
cerebellar cortex supplies the tonus; one must assume that it has
a centre for the tonus which is directed against the
sagittal axis of the body, i.e. «inwards» and also a
centre for the tonus away from this axis, i.e.
«outwards». When the arm is directed into the
horizontal plane one must assume that, as regards tonus, it is
being influenced by one centre for tonus in an upward direction
and one for tonus in a downward direction. Consequently one must
assume for each joint in the body the presence of four of such
tonus centres in the cerebellar cortex, one for each of four
possible movement directions. By close study of cases of isolated
damage to the cerebellar cortex and by suitable development and
adaptation of the Trendelenburg method, by which the cortical
centre can be temporarily paralysed by freezing, Bárány
also succeeded in establishing the presence and position of some
of these centres and thereby inaugurating a kind of topical
cerebellar diagnostics of a very promising nature. Although by
its very nature this study presents great difficulties, the
solution of which requires considerable time, many of the points
raised have already been confirmed from different sources, while
others must be left open.
After the outbreak of war Bárány's efforts were partly
directed into other channels which must be touched upon lightly
here although they are not directly within the framework of the
work for which the Nobel Prize has been awarded. As a doctor in
Przemysl he soon became aware that the usual methods of treating
infected cranial wounds gave very unsatisfactory results. In
almost all cases where projectiles had penetrated into the brain
taking with them infected particles of skin and clothing,
infection occurred which sooner or later led to death.
Bárány assumed that the so-called open methods of
treating wounds generally current at the time were directly
favorable to this infection and attempted in suitable cases,
after careful cleansing of the cavity, to close the wound with a
primary suture, thereby preventing continuing infection from
outside. With this method of treatment, which, although
Bárány was unaware of it, was also beginning to be used
in Germany and, particularly, in France, he obtained immediately
a considerable and obvious improvement in his results and when
Bárány came back in the middle of the war from a
prisoner-of-war camp in Russia he applied himself exclusively to
introducing the new method to the surgeons of his own country. At
first he met with definite and tough resistance, but, when the
experience of other countries became known and when Austrian
surgeons had tried the method themselves, when also
Bárány's great work on this theme was completed and
published, opinion changed and he was able to add another great
triumph to those previously achieved.
During the long period which he spent as a prisoner of war
without any kind of literature, laboratory facilities or other
scientific aids, Bárány was unable to proceed with this
great work or with research into the vestibular mechanism. His
speculative mind resorted then to the question of consciousness
and its anatomical-physiological explanation to which he
afterwards related a great part of his work, the first results of
which have already been published.
As head of the Otological Clinic in Uppsala Bárány has
already «established a school». Students from far and
wide have made use of the modest, provisional aids which he was
offered there and much important work has already been carried
out there.
* The Nobel Prize in Physiology or Medicine 1914 was announced on October 29, 1915.
From Nobel Lectures, Physiology or Medicine 1901-1921, Elsevier Publishing Company, Amsterdam, 1967
Copyright © The Nobel Foundation 1914
MLA style: "Nobelprize.org". Nobelprize.org. 19 May 2013 http://www.nobelprize.org/nobel_prizes/medicine/laureates/1914/present.html
