Year: 1874

W INV hbE8ths


Dr. Brown-Sequard lectured, last week,
TO large audience in the lecture-rnoH' VI
Plymouth church. Rreohiyn, upon the sub
ject, "'Tbo Mechanism aud the Seat in the
Brain of the Volitional, Sensorial, and
Mental Phenomena" Many prominent
physicians of both cities were in the audi
euce, although the discourse was a popular
one. After briefly describing the make
mp OF the nervous system and brain, the
lecturer said in substance:


Certain irritAtions of the brain not only,
but of many parts of the nervous system,
may arrest activity or excite morbid activi-
ty with greater variety OF phenomena.
The brain itself may act upon itself in this
way. Many parts of the nervous system
have especial power in this respect, and a
very slight irritation may produce tre-
mendous activity. Strong convulsions
have been ended by pairing away bit of
flesh wherein the irritation existed. The
causes are sometimes extremely slight in
deed. Frederick the Great (so-called), of
Prussia, ate his dinner one day-tlat was
all. There were some dozen dishes, among
the lighter OF which were beef, stewed in
brandy, potenta, aud a We Il pie, so hot and
highly seasoned that it seemed to have
been baked in-in a place very far from
this lecture room and he was thrown in
TO convulsions. Irritation of certain
muscle Of the eye may produce the catalyp-
tic state. What is the kind OF irritation by
which activity can be arrested? Respira-
tion can be stopped by an act of will, or by
pressure Of a certain nerve. Coughs, sneez-
ing, ana nic-cougns by the VIII, or by pres
sure of certain nerve in the face. Con-
sciousness ceases during sleep, but its ces-
sation is caused by an active irritation.
have had thirteen cases wherein convul-
sons Of the lower limbs have been stopped
by pressure upon the big toe. The con-
conyulsion which draws the head around
to one side can be stopped if, before con-
sciousness goes, the head is pulled around
10 the other side. 4 jet of carbonic acid
forced through the larynx will stop the
convulsions caused by strychnine or fol-
lowing loss of blood. A disease or injury
of the brain, even when slight, may pro-
duce great variety of phenomena of great
intensity, while it may again extend over
one entire side of the brain without pro-
ducing any phenomena whatever. The
two sides OF the brain are exactly alike in
function, and either of them is perfectly
competent TO perform the functions COM
monty attributed 10 both. Our education
OF the body is unfortunate in that II is one
sided. 1fthe left hand and the left side
were as good as the right hand and right
side il is extremely probable that two sides
g,ft ha NJ
and it would be a great gain If we had two
brains instead OF one. Some who are now
dumb would certainly gain the power of
speech in that case. The mind does not
play on the nerves as a man on the piano,
or receive sensations by ret urn vibrations.
In the first place the number of fibres of
communication with the body is extreme
ly small as compared with the number of
absolutely different motions we can per-
form or sensations we can receive. In the
second place the bond Of union may be al
most entirely affected. We cannot infer,
either, that the seat of irritation is the seat
| OF the mental act causing the activity which
the irritation produces. For irritation of
the bowels may produce aphasia, and
we should be unwilling to seat the mental
act in speaking In tho bowels. Tickle the
feet and the muscles of the face contract,
but we do not ass ume that the seat of will
for those muscles is in The feet. We know
| generally that the base OF the brain con-
trolls the muscles. The seat of vital force
has been placed in the medulla oblongata,
but animals live when their medulla is re-
moved. The mind has little power over
tho body as regards acts of will. What can
be done without the will is sometimes inn
mense. The will is no great power. Its
function consists only in pointing an end,
aud not at all in performing the movements
1t has indicated. A great many facts go TO
show that when the will has given an or
gan something 10 do that thing is done
without further trouble to the will, as
telegraphic dispatch had been sent and
done with. And the fact that when almost
all the fibres of the medulla oblongata are
destroyed sense and motion may be per.
feet seems 10 indicate that the communica-
tion has been by kind of telegraph fol
which one wire is as good as many, and
not by vibration of fibres wherein a sep


arate fibre is needed to transmit each order


from the will for each sensation to it.