Studies in Short Duration Auditory Fatigue. V. An Investigation of the Spread of Fatigue within Narrow Frequency Limits

摘要

If a tone is sounded in one ear and immediately a second tone is sounded, there is a decrease in sensitivity to the second tone. A 1000 cps. tone was presented to five observers for 435 msec. followed by a silent interval of 35 msec., then a test tone of 50 msec. was presented. The first tone was given at sensation levels of 30-90 db. in 10 db. steps. Frequencies of the second tone were varied randomly from 900-1100 cps. The greatest decrement in sensitivity was found for test tones from 990-1010 cps. in the form of a broad spread at the higher sensations levels. At the lower sensation levels only a slight effect was found. (Author)