HEARING LOSS FROM LISTENING WITH HEADPHONES
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.
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.