Page 76 - For Men of Understanding

muscle sac

4
stimulation the message reaches the spinal
2 The message is cord and a locomotion controller
1 called the motor neuron swings
Muscle sac transmitted from the 3 The nerves carry into action
receptors in muscles
contracts to the nerves the message

The spinal cord

5 The instruction is given
to muscles to take their
6 The location where motor neuron new position
8 contacts the muscle
The muscle
cells con-
tract
7 The muscles move upon the instruction given
locomotion by the motor neuron

The scheme illustrates the transmission of information from sensors in the muscles to the
spinal cord, which in turn gives the muscles new instructions. Each second while you read
these lines, billions of pieces of information transmitted by billions of receptors are evaluated
and the same number of instructions are given. Man finds himself born into this miraculous
system. He, however, has no share either in its creation or even in its operation.

be bent, the front and rear arm muscles - called "triceps" and "biceps" - should
be contracted and relaxed, and the muscles between elbow and wrist have to
twist the wrist. In every part of the act, millions of receptors in the muscles pass
on information immediately to the central nervous system about the position of
the muscles. In return, the central nervous system tells the muscles what to do
in the next step. Of course one is not aware of any of these processes, but just
wishes to lift one’s hand, and does it right away.

For instance, to keep your body straight, many pieces of information
derived from billions of receptors in your leg muscles, feet, back, abdomen,
chest and neck are evaluated and a similar number of commands are given to
the muscles each second.
Nor do we spend extra effort to speak. Man never plans how far apart the
vocal cords should be, how often they should vibrate, in which sequence, how
often and which of the hundreds of muscles in mouth, tongue and throat
should be contracted and relaxed. Nor does he calculate how many cubic cen-
timetre of air should be inhaled into the lungs, and how fast and in which fre-
quency this air should be exhaled. We could not do this even if we wanted to!
Even a single word uttered from the mouth, is an outcome of the collective
working of many systems stretching from man’s respiratory system to the ner-
vous system, from the muscles to the bones.
What happens in case of a problem in this co-ordination? Different expres-

sions might appear on our faces when we want to smile, or we might not man-

74 For Men of Understanding