Hearing in Advanced Age
1969 Volume 12 Issue 2 Pages 173-177
Details
1969 Volume 12 Issue 2 Pages 173-177
Hearing of the elderly people who showed almost normal pure tones thresholds below 1000Hz was discussed.
Filtered speech (1200Hz low pass) test, speech test using synthesizede vowels and directional hearing test were used for the analysis of the hearing.
These elderly people had good discrimination scores for the synthesized vowels of which the duration was only 16msec, 24msec (2 or 3 foundamental waves), or whose F1 and/or F2 was shifted from the original positions, on the other hand poorer results than those of the young people were obtained in the filtered resonants (1200Hz low pass).
It was suggested that those results were related to the decrease in number of ganglion cells of the central nervus system.
A coding and decoding system and its distortion seen in the retrocochlear lesion were demonstrated using a model.
