Evening star., 1940-12-21
Of Stors, Men
And Atoms
Notebook Of Science Progress
In Field, Laboratory
And Study
BIZ Thomas r. Henri.


Rough trails in the brain are blazed
before birth.
This is the finding reported by Drs.
Marion Hines and E. P. Boynton, Car
negie Institution of Washington SCI
entists, from a seven-year study of the
functions of monkey brains in their most
primitive states.
Stretching across the brain little in
front of the mid-line is a narrow strip
known to neurologists as the pre-cen-
trail cyrus. In adult life every point on
this strip controls the movements of
some specific point on the body. When
one point is stimulated by an electric
current, for example, there is movement
of the first joint of the little finger An
other point closely connected with the
speech area in humans, controls move
ments of the tongue. These are the CEN
ters of voluntary motion. Without the
little finger point, for example, one could
/ not move that digit merely by willing
to do so.
Quite different, Drs. Hines and Boyn-
ton found. are the conditions just before
birth Then electrical stimulation of
points on the pre-central cyrus brought
forth not specific but general motions
suggesting inherent racial patterns of
behavior. Stimulation of the facial area,
for example, brought forth whole COM
al nf nc IF
or licking When other spots were stimu-
lated they brought forth general pat
tern of movements suggestive of moving
forward.
Only a few points were found that
could be stimulated at all. They were
separated by silent areas" which were
not yet wired" to their respective
muscles on the outside of the body.
Other areas were found which they call
"chalistic points" stimulation of which
produced general relaxation of the body
muscles.
Almost Immediately after BIRTH they
discovered, these conditions began to
change. The points on the brain one
after another became tied up with their
respective muscles, the silent areas grew
smaller and smaller.
after BIRTH" they report, "the move
ments elected by stimulation Of the pre-
central cyrus at each stage of growth
followed a definite pattern correlated
with the type of posture. progression and
general behavior characteristic of the
animal at the same stage. 1t is note
worthy fact however that certain COM
plexly integrated muscular reactions were
elected by electrical stimulation before
the animal exhibited them spontaneously.
This hints that in the nervous system
anatomical connection precedes func-
tional use.
The threshold of sensitivity to the
electrical current became lower with age.
The stability of sensitive point, the
regularity with which a response could
be obtained increased"
What happens, Drs. Hines and Boyn-
ton believe, is an hitherto unsuspected
phenomenon in brain development-th
establishments of inhibitions. Large
areas of the brain, especially of the pre-
central cyrus, work originally as units.
Gradually influences of an unknown
nature develop which prevent center
of movement from acting upon anything
but the muscles of the little finger, the
big toe, etc.
The Division of Reptiles of the Smith
sonian Institution received from Florida
the other day fossil snake" black and
about yard long, which had been found
under about Is feet of mud in some
dredging operations.
1t obviously however, was not fossil
but an animal which had died quite
recently-perhaps killed in the dredging
work which had brought it to the sur
face. Also it was obvious, once the ex-
perts had started work on it, that it was
not a snake since it had rudimentary
legs, almost microscopic in size. What
ever it might be, it was most loath-
some creature.
After little study the reptile experts
found that they had perhaps the least
known of North American animals. the
amphiuma, sometimes known as Congo
snake. 1t is a salamander member of
the amphibian family to which frogs and
toads belong 1t spends most of its life
buried in the mud where it lives on
larvae of other salamanders and on fish
eggs An breathing creature, it must
come to the surface for air every few
hours.
Late each summer the females leave
their dark mud graves and come on
land to lay. their eggs, coiling themselves
around these until they hatch.
The amphiuma is seldom encountered,
is rare in collections and is barely men,
toned in standard text books of natural
history. Confined to the Southeastern
United States, it is considered highly
poisonous snake although actually it is
harmless. Very rarely one is caught on
fish hook. 1t is probably the slimiest
of living animals and so slippery that
it is impossible to hold one in the hand
1t has some close relatives which are
much better known, but which much
more obviously are not snakes and are
not so secretive in their habits. One is
the giant salamander of China and
Japan, the largest and most active of
the race. It makes its home in crevices
under rocks in running streams. The
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