The influence of timbre and loudness on the localization of sounds / by Charles S. Myers.

  • Myers, Charles S. (Charles Samuel), 1873-1946.
Date:
[1914?]
Catalogue details

Licence: In copyright

Credit: The influence of timbre and loudness on the localization of sounds / by Charles S. Myers. Source: Wellcome Collection.

    10/22 (page 274)
    have termed incidence. Laterality can only concern whether the sound is placed to the right or left of the subject or somewhere in the median line; and, as I have already said, errors in laterality were never found in these experiments, provided that the auditory acuity of the subject’s two ears was normal and that the position of the sounds relatively to the two ears was such as to produce the required binaural difference (or equality) of loudness. On the other hand, whatever factors are responsible for the determination incidence should hold for the horizontal, as well as for the median sagittal, plane. Experiments carried out on five subjects with variator sounds given in the horizontal plane reveal just the same inaccuracies as have been described for the median sagittal plane. The first of these subjects localised all sounds— whether fore (45° h.), side (90° h.), or aft (135° h.)—behind his ear, the second localised them all in front of his ear, the third localised fore and aft sounds in front of his ear, while the fourth and fifth subjects gave too variable a localisation to allow of any more general statement than that they showed total inability to distinguish fore, side, and aft sounds from one another. Two questions naturally arise :—How is it that previous observers, while recognising a liability to err in the localisation of such sounds, have not laid stress on the initial grossness of the errors of localisation revealed under the conditions of these experiments ? How is it that these errors do not play an equally prominent part in our everyday life ? We are all aware of occasional errors in fore and aft localisation, but it is relatively seldom that they are brought to our notice. Now, one important factor consists in familiarity with the sound. As we shall see, with practice every subject learned to localise correctly. Another important factor employable in everyday life, but eliminated to a very large extent in these experiments through the use of a head rest, consists in head movement. On several occasions in the course of these experiments I expressly instructed my subjects to move the head while they were listening to the sound, whereupon their errors in localisation were immediately and often quite accurately corrected. In some experiments, moreover, performed in the open air, in which I acted as subject, where the vowel E was spoken by an assistant and his position had to be ascertained, I localised both fore and aft positions forward, but when the experiments were repeated with a small head movement carried out during the production of the sound, I at once changed the localisation of the rearward sounds from fore to aft. Obviously, by turning the head, the sound is alterable in intensity; for,