Intelligibility of interaurally alternated speech

Cherry and Taylor (JASA, 1954) investigated the effects of alternating speech between the left and right ears
and showed that intelligibility is disrupted when the alternation rate is high.

The effects of speech alternation are illustrated with audio examples below. You will need headphones or a
pair of spatially separated loudspeakers. The first example is of a male voice saying "The watchdog gave a
warning growl." This is followed by several processed versions in which 50% of the speech waveform is
alternately played to the left and right channels. The audio examples illustrate alternation rates of
1, 2, 4, 8, 16, 32, 64, 128, 256, and 512 Hz. The figure shows the waveform of the sentence processed
with a 2-Hz interruption rate. 


           .WAV format                           .AU format

  1. Original sentence                                    Original sentence
  2. 1 Hz interruption rate                              1 Hz interruption rate  (see figure)
  3. 2 Hz interruption rate                              2 Hz interruption rate
  4. 4 Hz interruption rate                              4 Hz interruption rate
  5. 8 Hz interruption rate                              8 Hz interruption rate
  6. 16 Hz interruption rate                           16 Hz interruption rate
  7. 32 Hz interruption rate                           32 Hz interruption rate
  8. 64 Hz interruption rate                           64 Hz interruption rate
  9. 128 Hz interruption rate                         128 Hz interruption rate
  10. 256 Hz interruption rate                         256 Hz interruption rate
  11. 512 Hz interruption rate                         512 Hz interruption rate


  


   

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