HEARING LOSS FROM LISTENING WITH HEADPHONES
or
THE ROLE OF THE BODY IN HOW WE ARE AFFECTED
BY SOUND
©1983 The Anstendig Institute
I.
A SHARP INCREASE IN HEARING IMPAIRMENT HAS BEEN TRACED TO THE USE OF HEADPHONES
It
has long been known that listening to loud recorded music can endanger one's
hearing. Audiologists, however, have observed a sharp increase in hearing
impairment since the introduction of personal stereos that use headphones.
Many
reasons for the increase in hearing impairment due to headphone listening have
been offered, but the most important question has not yet been fully addressed.
That question is: why is there a distinct tendency to adjust the volume so that
the music is considerably louder when listening with earphones than when
listening with loudspeakers? The usual answer is that the listener turns up the
volume to drown out extraneous noises. While that might possibly be part of the
reason, the results of The Anstendig Institute's research into how we hear
indicate that it is not the main reason.
II.
THE BODY PLAYS A CRUCIAL ROLE IN EXPERIENCING THE EMOTIONAL -CONTENT OF MUSIC
The
Anstendig Institute has spent a great deal of time studying the role the body
(i.e., the torso) plays in the musical experience (or in any other type of
sound experience). This has been accomplished by isolating the subjects' torsos
from sound waves1 while they listened to recorded musical
performances that were familiar to them. Before the experiment, enough time
(over a period of days) was taken for the subjects to become familiar with
their reactions to the emotional-expressive content of the test recordings
under normal listening circumstances. With their bodies shielded from the sound
waves, the subjects did not have the same quality of emotional experience;
either they did not experience the music emotionally at all, or the experiences
were less intense, more sporadic, and more difficult to sustain. Because of the
known undependability of our memory for sensory perceptions, emphasis was
placed mainly upon whether or not the subject had an experience and how intense
the experience seemed to that person. Fine differentiation of the experiences
was not stressed. We recognize the scientific questionability of subjective
impressions. But we believe that the results lead to the insight that the body
does play a crucial role in how we experience sound and that, in music, it
plays the greatest role in the way we experience the emotional-expressive
content.
There
are no abstract, i.e., purely mental, emotions; an emotion is a physical
experience that is produced by the body and it cannot be experienced unless
one's body is in the physical state or attitude that is characteristic of the
particular emotion (one cannot be sad, for example, with the corners of the
mouth turned up and the face in the attitude of a smile, nor can one be jovial
with the corners of the mouth turned down and the face in an attitude of
dejection). Emotions can be externalized, in which case they are experienced
when the body is allowed to assume the attitude of that emotion (grief, horror,
sadness, supplication, etc., are all attitudes). It is also possible for
emotions to be internalized, especially when they are caused by external
stimuli, such as music, that contain the vibrational characteristics of the
emotion. In this case, the emotions are experienced internally without the body
assuming the whole outward attitude of the emotion, although some outward
physical indications of the emotion can remain, such as tears in the eyes. One
cannot, however, experience one emotion with the body in the attitude of
another, different, emotion, and even when internalized, the emotions still are
physical processes (quickenings or calming of the breath and heart-beat,
agitation, internal sensations, poignant pains in the chest, etc.).
Understanding the fact that emotions are physical--not mental--processes is
essential to an understanding of why people tend to listen to music louder with
headphones than when listening with their whole bodies exposed to the sounds.
III.
WITH HEADPHONES IT IS IMPOSSIBLE TO DUPLICATE THE EXPERIENCE ONE HAS WHEN
LISTENING TO MUSIC THAT FILLS THE ROOM
People
listen to music to have a physical-emotional experience, whether it is the
exhilarating experience of dancing to rock music, the bittersweet sadness of
listening to "Where Have All The Flowers Gone", the overwhelming fear
of judgment in the Dies Irae of a Mozart or Verdi Requiem, the
jokingly nasty irony of Mahler's two settings of Saint Anthony and the
Fishes, or the compelling sweep of a rumba or cha-cha-cha. These
physical-emotional experiences are what people want and are what they expect to
happen to them when listening to music that they like, at whatever volume level
they are used to hearing it. But when they put on headphones and start
adjusting the volume, something is missing when the volume reaches their usual
listening level. They are not experiencing the music the way they are
accustomed to experiencing it. So they keep turning the volume up higher until
something begins happening to them that is closer to the experiences that they
are used to. But with headphones, because the sound vibrations cannot reach
their bodies, they can never duplicate the musical experience that they have
when the music fills the room, affecting their bodies as well as their ears.
They therefore keep turning the volume up until it reaches ear-damaging levels
and mistake the excitation caused by that irritation for the physically
compelling effect that the whole-body experience provides.
With
headphones, the body is also usually out of synchronization with the music
because the listener's environment, which is also a source of vibrations and
affects the body, is not vibrating in the same way as the music. This is
especially true in relation to experiencing the emotional content of the music
since the body has to reproduce the emotions if the listener is to experience
them. Because the desired experience does not happen, the listener turns the
volume up louder in order to get into the "beat" (the rhythmical
flow) of the music. But there remains a dissonance between the rhythmic flow of
the music and that of the listener's body in its surroundings.
Since
the physically stimulating experience that most people are seeking by listening
to music is to a great extent caused by the musical vibrations hitting their
bodies, and since the principal reason why people turn the volume up louder
while listening with headphones is to compensate for that missing physical
stimulation, the first and most important step towards protecting people from
hearing loss due to listening with headphones is to wary them very strongly that
they will not be able to duplicate the experience they are used to when
listening live or with loudspeakers.
IV.
EQUALIZING THE RECORDINGS WOULD REDUCE MUCH OF THE DAMAGE INCURRED AT LOUD
VOLUME LEVELS
Even
with warnings, there will still be people who will not be satisfied listening
at lower volume levels. This brings up the question of whether anything can be
done to mitigate the dangers. It has long been proved that we are very much
more sensitive to certain frequencies than to others, and that those immense
differences in sensitivity become greater and greater the louder the music is
played. Also, the volume of sound produced by instruments and by the voice
peaks in these same frequency ranges to which we are most sensitive.3
Since we do not hear the sound source itself, but rather the vibrating of our
own hearing mechanism after it is stimulated by the vibrations from the sound
source, the fact that we hear some frequencies louder than others means that
our ears, which are more sensitive to these frequencies, are more easily
damaged by them. If the manufacturers of tapes would equalize recordings by
cutting down the volume in those frequency ranges to which we are most
sensitive (in proportion to the average sensitivity to them), much of the
hearing damage that occurs with and without headphones would be substantially
reduced and the sound would also be improved. This would not amount to a
precise equalization of the contents of the recording, since the equalization
has to be "fine-tuned" to the volume level at which the music is
played and to the listener's state of relaxation.3 But it would
definitely be an improvement that the the listener could further adjust when
listening in situations that allow the use of an equalizer.
To
recapitulate:
Because
listening with headphones cannot duplicate the experience of room listening,
people tend to play recordings at dangerously loud volume levels when using
headphones, and the louder they play the music, the more physically sensitive
they become to the frequency ranges that are loudest in the music itself.
In
order to avert a disaster of near epidemic proportions, it is essential that
the public be strongly warned that, when listening with earphones, they should
not attempt to reproduce the experiences they are accustomed to having when
listening with loudspeakers. It is also important that recordings be
pre-equalized, reducing the frequency ranges to which we are most sensitive.
1
The subjects were covered to their neck using both a wooden
construction with metal shielding and special clothing of reflective material
developed for NASA.
2
We want to make clear that we are speaking mainly of the body's
being subliminally affected by the physical sound waves whether or not they are
consciously perceived. In other words, this effect is not dependent upon a
threshold above which the subject consciously notices the effects of sound
waves on the body, the accepted values of which we question. (From our
experience, the accepted value of 120 dB for the threshold of feeling seems too
high, especially for sensitive people or people who are in a relaxed state
under familiar circumstances as opposed to a laboratory test-situation.)
3
Pertinent papers, explaining in detail the facts referred to in
this paper are available from The Anstendig Institute free of charge.
The
Anstendig Institute is a non-profit, tax-exempt, research institute that was
founded to investigate the vibrational influences in our lives and to pursue
research in the fields of sight and sound; to provide material designed to help
the public become aware of and understand vibrational influences; to instruct
the public in how to improve the quality of those influences in their lives;
and to provide the research and explanations that are necessary for an
understanding of how we see and hear.