voice
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Talking with the dead – how scientists resurrected a long-dead voice

Nesyamun was a priest from Thebes who lived during the reign of Pharaoh Ramses XI, 1099-1069BC. He died more than 3000 years ago, so he’s probably the last person you’d expect to be speaking in a lab in 2020. However, a team of academics at Royal Holloway, University of London, the University of York and Leeds Museum have managed to replicate his voice, using medical technology and 3D printing techniques to make the dead speak again.

Where does the voice come from? The voice box, or the larynx, as it’s technically known, is the reason that humans are able to speak. It’s a small, hollow tube that sits at the top of our windpipe, and it’s anchored to the bone that’s connected to our tongue. The larynx is made of cartilage, and it contains small bands of tissue (the vocal cords) that can expand and contract – the cords pull together, and the air that rushes through causes them to vibrate. These vibrations produce sounds, but this is not enough in itself – there’s also complicated interplay between the vocal cords and our oral and nasal cavities that helps to modify this sound into words.

He died more than 3000 years ago, so he’s probably the last person you’d expect to be speaking in a lab in 2020

This is where Nesyamun comes into the picture. To copy the sound produced by his vocal tract, the team needed to copy the exact dimensions and 3D-print a new one. This is normally only possible when the soft tissue of an individual’s vocal tract is intact and, in most corpses, the soft tissues decay quickly. The technique, then, will not work for someone that is long decayed. However, because Nesyamun was mummified and his body well preserved, a CT scan provided all the information the team needed.

They printed out a new vocal tract, and then generated a ‘voice’ using an artificial larynx sound, which approximated the lungs and vocal folds of an adult male’s body. This is the method commonly used in modern speech synthesis systems to emulate the human voice. Currently, the voice has been reproduced as a vowel-like sound (reminiscent of a sheep’s bleat), but the team are working on techniques to help turn that sound into full sentences. According to archaeology professor and study co-author, John Schofield, the next step will be to use computer models, “to generate words and string those words together to make sentences.”

Because Nesyamun was mummified and his body well preserved, a CT scan provided all the information the team needed

The obvious question is, how close is the sound to Nesyamun’s real voice? According to Daniel Aalto, a communication sciences and disorders researcher at the University of Alberta (who was not involved with the study): “Overall, I think it was a well-made study. But what makes a voice recognisable in humans – and what creates our unique voice – is not only the vocal tract shape but also how we are using our vocal folds.” How we move our lips, the shape of our tongue or how we breathe all alter how we sound. Importantly, too, the sound emerges from an artificial throat at rest, whereas a living person actively modifies their vocal tract to form any specific vowel sound. This can only ever be an approximation of a voice, extrapolating from the physical data and filling in the blanks where data (such as Nesyamun’s soft palate) is unavailable.

In case you feel that this procedure is somewhat ghoulish, Schofield explained that it was Nesyamun’s “express wish” to be heard in the afterlife – indeed, it was part of his religious belief system. “It’s actually written on his coffin – it was what he wanted,” Professor Schofield said. “In a way, we’ve managed to make that wish come true.”

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