Year: 1874

It


BY DIR. G. +. BROwN-sEQUARD.


The title of this address on the pretended
locaaion of the mental and the sensora functions OF
the BRAIN Dr. BrownSequard began by saying that the
subject has been rendered difficult by assumptions
OF Psychologists upon insufficient data. Among the
views which have been recently put forward upon the
locazation OF nervous power IN certain parts OF the
brain, there two OF Importance: One re-
lates to the seat Of power actuatng
muscles and the other is as 10 the seat OF
sensation for different In the latter particular


shall review especially the assumption IN respect 10
the old views respecting the ocalizat0n in the BRAIN
ward rd0 by Miller of Berlin which for time had great
popularity. IL was however. absolutely wrong IL
assumed that as regards the power OF me acton .,
the will on the muscles the brain must
be considered as the keys OF piano. When
the soul the will acted TO produce moyement II Was var
supposed act upon the nerves az the nger upon ne
keys OF piano. As regards sensation tue mechahls
supposed to be equally simple II was snpPOsse
transmitted through the whole system, WITHOUT aut
break. through the spinal cord to the brain.


DEFECTS OF THE MECHANICAL THEORY OF THE


NERVES.


This theory assumed that sensation was conveyed
through the body by tho the bells rung In
apy part OF a hotel have the sound conveyed along
wires to central Office, where the fact is recognized
from where the call may come. But TINS assumption
was Just false it simple There Is no such com
pact continuity Pathology shows that there Is no fou-
dation for such views. In the ,nrst place, the
spinal cord (which is the organ through which
ali the nerve hbers or conductors coming through
brain have pass, and also all the conductors com


ing from the periphery to the brain nave 10 pass can
be destroyed in great part without destroying either
the power of motion the power OF receiving sensa
tions There facts respecting the medtHta OMon'
oatI which as you know is between the brain and the
spnal cord which place this Ond the reach OF ques
tion, and prevent Miilers theory OF mechanism from
having our permanent acceptance. -


There are other facts relating to this question which
Without brain which still exercise the functions that
IN he
as tho AnphiOrus tdnceOtdtus In others we hhd tne
part that answers to tue brain Is hardly aIse enough
Now II you hold your arm upon table
and try to make dots with pencil IN IN your t,r
will be able to make perhaps 1000 points WeD snch
power as that exsts-and indeed tno numoer wnicn @
have given is not too large, as have counted 192
points made by myself, and am miserable draughts-
mali sueh po%er enstS h WIN 50 i'm aS nDmher nf


bers IL would require to establish communication be-
tween the brain and the periphery were all the noers
Again If we divide portion OF the spinal cord
movement or BOTH below the point of division; but the
communication Is not utterly severed thefe Is NOT NOT
always complete paralysis ther should be to satisfy
the conditions of the piano-wire theory.


In fact there Is no necessity or more than very rev
hbers to establish communication between the brain
and the spinal cord IL Is like telegraphc com
munication than movement along wire, by when
sensation is conveyed from the periphery 10 the brain,
or tho brain transmits Its orders 10 the periphery
Let me give an instance OF what mean. III piece
of ice is laid upon my foot, nave M az GMSe uae
the sensation OF the extent OF the surface that
touches me- the Of the weight of the ice, and,
il t Is left upon my foot the sensation OF pain, and tue
sensation the skin to which the Ice Is applied All
those forms Of knowledge communicated at once.


believe that all these Impressions communicated
to the spinal cord. which single wire transmits II To
the brain.


PERTINACIOUs ADHESION TO EXPLODED THEORIES.


Now as to the two sides Of the BRAIN the old view was
that the left side OF The brain the movements OF
right side OF the body aud the right side governs
the movements OF the left side of the body and that
there is similar view respecting perception and SEN
satlon. Facts oppose this view. L am sorry 10
say that physicians adhere TOO pertlnaclousiy
TO old views like this, without regarding more
recent discoveries. We are constantly holding on
to old clothing, wearing 1t when it Is worn out
am sorry TO speak thus severely Oh pioesslon which
my but the discoveries OF tne last ten years seem
scarcely to be recognized by the medical faculty
Younger members Of the profession should seize oppor
tunies TO make themselves familiar with the advances OF
discovery Take such facts as this for instance
Onehlrd one-nal the brain may be utterly destroyed
without any symptom of the injury; then one-thrd OF
OF either half be DESTROYED without any indication


OF Ier9 OF ees Sss or W OF the ne er But
Abercrombe and spicer relate still more remarkable
lady Of refinement had mad very slight symp-
OF any trouble with the BRAIN She had gone TO tea
party and enjoyed himself there had walked about and
talked as II ln her usual health Nothing IN her sensa
tions indicated serious trouble. she was found
dead in her bed the next morning. The autopsy re-
vealed that onehaf OF her brain was entirely DESTROYED
and moreover that this destruction had been OF long
standing. The account OF this is to be found in Aber
cromUe, page 1T. 4th edition.


Let consider the question CT the locality OF the
intelligence OF the BRAIN Most Psychologists are agreed
that this s the gray matter OF the upper parts 0f the
brain. But the method OF communication is still open
to research Here the lecturer went TO the blackboard
and drew figure somewhat like sheaf OF wheat without


band around IL the stalks representing the nerves the
heads OF wheat representing the cells. Now you may
subtract from hls Dy disease OF otherwlse say the
upper third and still you have the nerves and the nerve
cells and the processes be carried on but in the
progress or such destruction downward there would
eventually be reached point where the functions OF the
the facts as we ind them. But there is no case on
record where the gray matter beth sides OF the brain
has destroyed without the loss of intelligence aud
must regard that gray matter as the seat OF the in
tellgence But vast portions may be removed before
the loss Of intelligence becomes apparent Tnls nave
myself tested and proved oy YlYseetion OF the lower
animals,


the gray matter may be diseased on both sides Of the
brain In these the OF speech does not seem
diseased person has had the power Of speech restored
during delirium The speech is coherent though the
faculty OF speech is not actually lost in such
ana yet find that the third frontal conyoiution Is
deiruin But the most argument s found in
the cases that have seen, where the third frontal
DESTROYED and yet the patients have not lost the
power of speech. Therefore the theory is itself
S shOw that the question of rshhSndedness or left
handedness does not apply In these consideraons The
lecturer here OF Jacmet Of Montpelier and
Mr.. Prescott-Hewtt OF London In theatter case the
patient had suffered destruction OF that part OF the
brain for years, and yet for 10 years had spoken


THE LoCALIzATIoN OF CENTERs OF MOTION IN THE
BRAIN.


We shah now take up the question of the ocalizaton
OF motion in parts Of the brain surprised
at the avdy with which certain series Of facts have
been accepted as proof of this theory in England.
very eminent man. Of whom should not like TO say
ANYTHING severe, my friend Prof. Carpenter has ac
cepted those views. may say that all England has
accepted them. Prof, Huxley indeed has written Inc
that he oay accepted this view in part but cannot
! now he can accept part without accepting
the WHOLE where the part incorrect The famous
experpents OF Dr. Ferrer OF Guys Hospital must here
he Considered AS you will see they are not, however
concInsiye Nv the application OF gavansm TO certain