The herald., 1895-02-06
NJ ANS BRAIN.

A Photographic Plate, RetainIus Impe es
aud Yielding Thorn Under IS fiuence.
Journal des Dsbats: Tho nervous
system is enclosed in a bony case COM
posed of the bones OF tho head and the
vertsbrn; the encephalos is contained
in the crsnisl cavity, the spinal marrow
in the spinal canal. The marrow and
the brain do not completely fiji these
cavities, and the interstices are filled
with liquid, which prevents shocks and
com preesione. From the marrow
and the brain the sensitive
and motor nerves start, which
carry sensations to the two CEN
trail organs and take back the move
m ents. A sensation brought to the
brain by sensitive nerve generally
provokes o motion, q contraction. In
such cases the brain 10 center, Ia
which the impression is transformed
into action. But very often the i'm
preston is not followed by any action.
The nervous system then becomes q
central storehouse for Impressions. Mr..
Br;ssaud very aptly compares ths brain
to Photographic plate which rotains
thu image and only yields it under the
Influence OF developing body. The
brain. particularly in Infancy, stores
up numerous sensations, which late r
cause actions. The cerebral center
retains these images. that is, these
lasting rsmem brancss of outward ex-
elements.
The gray substance which forms the
outside covering Of the brain is q senei-
tive plate on which images OF the outer
world are impressed. The nerves con-
duct the electric, heat, light and so md
waves to this cerebral covering. whore
they are impressed no on the cylinder OF
a phonograpb. The i'm IMPRESSION is more
or less exact according to the nature oil
the cerebral instrument; it is more or
less profound according to the breadth
or the number Of tho vibrations OF the
waves. The impression thus formed
becomes q recollection; it tends to be-
come effaced with age IT submits to
alterations according TO notifications OF
the impressed surface. These images
may remain unused in the brain for
long tins, as the Photographic plates in
their box. The idss OF an objact is
thus always tho recollection OF an object.
The association OF idess often causes
an association OF movements, called at
tomato A little girl, Tor instance.
learns to knit. At first she Is very awk.
ward. but gradually she progresses and
the work almost does itself, until finally
she walks, talks, and learns her lessons
while knitting. The different automatic
centers occupy localized regions in the
brain. The mort celebrated is the CEN
ter OF language, localiz ID about 1925 by
Bouillaud in the front tote of the brain.
When any injury whateyer-rnpture OF
a blood vsssei. soitening OF the brain
tissue, etc.--attacks this lobe. the
faculty of language disappears AMI the
patient ia stricken with sphasia. There
ara several aspects of this dieesse.
Sometimes the patient cannot speak,
but is able to xpress his thought in
writing; this is aphasia Of articulation {;
others are able to epsak, but cannot even
write their own names; this ia graphic
aphssia; others, though not at all deaf,
have no idea that the name they
hear pronounced :s their own
name, although they may be able to
speak it, read it or write 1t; this 10 au.
ditive aphasis: others, finally. without
being blind, have Lost the faculty OF
reading. although they can still write /;
this ia visual aphasia. Right. han dsd
aphssics. unable to speak, have suffered
acme injury OF the shird left frontal
circumvolution, and left-handed ones OF
the corresponding right one. Those
who cannot write have some injury to
the second frontal circumvolution.
Those who have Loaf the faculty Of hear
ing have a wound in the first left frontal
accommodation, and those who cannot
see writing, one OF the second parietal
left oircnmvolution. CHARIOT has said
and M. Brissaud repeats: I'm studying
cerebral affections the nature OF the in
jury is almost matter of indifference
the localization 10 everything" One
may become sphasic in consequence of
an attack of spoplexy. q blow or shock
which causes an abscess of the brain, or
a cancer which pressed on that organ.
1t can even be produced by tubsrculo-
sic. Alas that the brain should be 60
deli cate an organ"