Our senses tell us about the world, but they also reveal a lot about ourselves. On the latest installment of Clever Apes, we find that research into cochlear implants helps us understand how all hearing is really both mechanical and subjective, machine and mind. Then we meet a mathematical neuroscientist (or would that be neuro-mathematician?) who has solved the equations behind visual hallucinations (hint: it involves a fun romp into quantum field theory! Oh yeah, and it also may help explain cave art and religion … more on that in a future post.)
Meanwhile, as we discuss in the episode, cochlear implants work largely on the same principle as the vocoder (hear a fascinating history of the vocoder from our colleagues at Sound Opinions). This involves encoding sound – as in, ripples in air pressure – onto a piece of white noise. The result is that familiar robotic-type sound that lovers of Kraftwerk know so well. Dr. Valeriy Shafiro offers a fine demonstration of the effect at his lab's web site (heard only in Internet Explorer, I'm afraid). You can plainly hear how speech comes across much better than environmental sound.
Another Rush University researcher, Julia Cheng, is doing work on cochlear implant patients' ability to appreciate music. Incidentally, Mary Callahan, the patient in the story, says she can really only appreciate music that she remembers from when she had in-tact hearing. She laments that she went deaf when Cindy Lauper's "Girls Just Want to Have Fun" was topping the charts, leaving her musical palate very limited. Though I have to say that Lauper has worn better than I ever would have expected.
Also, you’ll notice Clever Apes is a tad shorter this month than in past episodes. This is part of what we hope will soon become the new-look, twice-monthly Clever Apes, heard regularly during Morning Edition and via a more robust podcast. So don’t hate.