ate these organs (at
least in an inchoate and partial way)--that is, we sound the note to
ourselves--when trying carefully to judge of its pitch." (_Elements of
Physiological Psychology._)

Much more important in the study of the problem of tone-production are
the adjustments of the hearer's vocal organs which were named the
sympathetic sensations of tone. This peculiar auxiliary to the sense of
hearing calls for the closest attention.

Sympathetic sensations of tone are awakened in the hearer through the
mere listening to the sounds of the human voice. Vocal tones impress the
listener's ear in a manner entirely different from any other sounds. Not
only are the tones of the voice heard, just as other sounds are heard;
in addition to this, every vocal tone heard is mentally imitated, and
this mental reproduction of the tone is referred in imagination to the
hearer's own vocal organs. Besides hearing the vocal tone as a sound
pure and simple, the listener is also informed of the manner of throat
action by which the tone is produced.

This mental imitation and judgment of vocal tones is not a voluntary
operation. On the contrary it cannot even be inhibited. It is impossible
for us to listen to the voices of those about us, even in ordinary
conversation, without being to some extent aware of the various modes of
tone-production.

This idea of the mental imitation of voices may impress us at first as
highly mysterious. Sympathetic sensations of tone have been felt and
noted, probably ever since the human voice and the human ear were
developed. Yet the process is purely sub-conscious. It is performed
involuntarily, without thought on the part of the hearer, even without
any consciousness of the process. The hearer simply knows how the voices
to which he listens are produced. A throaty voice simply sounds throaty;
the hearer feels this, and pays no attention to the source of the
information. We take it as a matter of course that a nasal voice seems
to come through the speaker's nose. Why a certain quality of sound gives
this impression we never stop to inquire. The impressions of throat
action conveyed by other people's voices seem so simple and direct that
nobody appears to have thought to analyze the psychological process
involved.

This psychological process is found on analysis to be highly complex. In
addition to the actual physical exercise of the sense of hearing, three
distinct operations are performed in imagina