The Worcester spy. [volume] (Worcester, Mass.) 1898-1904, 1899-07-18
REACTION TIME.
Dr. lindley Performs Interesting Expert
ments illustrating This.

ments Illustrating This.
DIR. Lindley lectured on Memory, "
and began with several experiments
with chronoscope, illustrating reac-
t1on time. When a word is called out,
the subject makes electric connection
| by means of a key with the machine,
ana as soon as he receives an associa-
tlon, breaks the circuit and the time
IS read off on a dial. The first asso-
cation time showed 2S4 of a second.
Man reacted to boy" "cat" to
cog, courage" to bravery" etc.
The name of a concrete thing takes
the shortest time, verbs come next, then
abstract terms. Another experiment
is made without apparatus A list of
typewriter words is given out. When
the time is called, each subject writes
opposite each word the first associa-
tlon which comes to him. After so
seconds the writing is stopped and the
tlme OF each association may be deter
mined by dividing the time occupied by
the number of associations. About two
seconds was the average time in the
experiments tried yesterday.
Memory is defined by Prof. James as
lhe knowledge of thought or act
when we are conscious of having be-
Iofe Something is recalled The re-
qulsltes for an active memory are:
production of an image. This must
recall something; we must be able to
locate 1t IN place and time, recognize it
ny certain landmarks in our mind Ami
lildls perhaps do not recall time but
there are stories of animals chastising
those who tease them, and from this
we may be sure that there are images
formed and perhaps some associations
Most of us have our own individual
landmarks. As our experiences become
more complicated, there comes a need
oI common landmarks for society such
as the calendar
The rentention of an image is a MIRO
ly physical act. The brain is like wax
that will take an impression and hold
II; II is like the cylinders of a pho1o-
graph. There must be a recall before
we can De sure of retention The first
theory of why thing was retained is
that there are vibrations set up that
continued all the time, growing less as
TIME advances, but which may be re-
gained to certain degree. Second, that
the nerve cells become modified BY
these impressions, and some imagine
certain shiftings in the molecules of
the cells. Third, the theory of dispo-
sltlons is perhaps part of both the
others, that there is a change brought
about by the vibrations.
This is, in fact the law of habit. like
the visual process in which an impress
sion will remain for time afterward.
This retentfveness varies greatly. In
some cases it is hereditary. Some peo-
pie have brains like wax, others like
Jelly, which vibrate but do not hold
impression. These men of marvellous
memory, these idiot savants, as they
are called, have this, due to inborn te-
nacity. This retentive memory varies
greatly in different bodily conditions.
man remembers better in the morn
ing than in the evening This probably
is caused by fatigue. This retention va
ries with age. AS the man gets older,
the brain gets harder and harder and
holds impressions longer.
Prof. James says that probably no
one was ever efficient who had not this
retentiveness. There comes a time in
our life, however, when we forget as
fast as we learn, and in old age there
is no reception, and very old men re-
member the acts of their childhood
better than things that happen from
day to day. This shows that the dying
away of retention is the very root of
memory, like man multiplying two
by four and dividing by three; he must
remember the multiplication before he
performs the division. If he let's the
first slip, he is at loss.
We do not remember those things
which do not interest us. The after
image will not only hold for a second,
but will recur again, then falls and re-
turns again, and if one does not attend,
it dies away, not to return. There is
no proof of this physiological condition
of memory, for We know nothing of
retentiveness until we begin TO recall
the images.
Ebbinghaus took a number of nom
sense syllables, which he memorized.
He found he could memorize in one
reading seven syllables, and it took
nine readings to memorize y. He found
also some interesting things about the
curve Of forgetting. He first found how
many times he would have to read
those syllables to memorize them, then
in reading them half an hour later, and
a day later he found that at the half
hour he had to read them one-half the
number of times of the first, and two
thirds times after a day.
pupil often says that he knows
something and cannot remember 1t, and
Prof James says that this pupil should
be treated differently from the one
who does not know. Men never forget
such things as swimming and bicycle
riding, which are very simple things to-