A favorite children’s game is to make a telephone out of two tin cans and a piece of string. Hobbyists with more advanced skills can make a functioning telephone with a relatively-simple electronics kit. It takes true skill, however, to do what two scientists did in 1929 when the turned a living cat into a working telephone.
Princeton University professor Ernest Glen Wever and his research assistant Charles William Bray were attempting to better understand the way the ear’s auditory nerve perceives sound. To do this, they needed an actual, functioning auditory nerve. The “volunteer” for their experiments was a cat.
With the cat well sedated, the researchers made a hole in the cat’s skull, located its auditory nerve, and attached one end of a telephone wire. The other end of the wire was connected to a telephone receiver.
With Wever holding the telephone receiver in a soundproof room 50 feet away, Bray spoke into the cat’s ear. Bray’s words came through on the other end of the connection. In other words, they had turned the cat into a working telephone.
The men made several modifications to their experiment by reattaching the wire to different parts of the cat’s brain and by regulating the blood flow to different portions of the brain. It was only when the wire was attached to the auditory nerve that it produced the desired effects. Not only did they confirm the role of the auditory nerve in sound transmission, but they also verified what was then only a theory — that the louder the sound, the higher the frequency.
Their experiments earned them no accolades from animal rights activists, but they did lead to several technological breakthroughs. Wever learned through the experiments that people with musical talent made the best sonar operators, owing to their ability to distinguish between nuanced sounds. The findings were put into practice during World War II’s submarine warfare.
The benefits of the cat telephone research are still being felt today. The research of Wever and Bray inspired the modern technology of cochlear implants. These technological marvels connect to the auditory nerves of the deaf, giving them the ability to hear.
No one advocates using your household cat as a replacement for an iPhone. Even so, the next time you see a friendly feline, whisper a word of thanks to its relative who unwillingly — but significantly — contributed to our understanding of the human ear.
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