24 Aug 2012
Paralysis sufferers could soon learn to talk again after scientists discovered how the brain allows humans to pronounce vowels, a new study has claimed. Scientists are investigating the use of brain waves to create a new form of communication which could return the power of speech to paralysis sufferers like Physicist Stepehen hawking.
Diagnosed with Lou Gehrig’s disease at 21, Hawking, now 70, relies on a computerised device to speak. The new research could pave way for prosthetic devices in the brain returning the power of speech to those paralysed by injury or disease.
Researchers followed 11 epilepsy patients who had electrodes implanted in their brains to pinpoint the origin of their seizures, with neuron activity as they uttered one of five vowels or syllables containing the vowels recorded. They found two areas, the superior temporal gyrus and a region in the medial frontal lobe, housing neurons related to speech and attuned to vowels.
Neurons in the superior temporal gyrus, responsible for processing sounds responded to all the vowels, whereas those that fired exclusively for only one or two vowels were found in the medial frontal region involved in memory.
FINDING VOICE: New brain study offers hope to patients like phycisist Stephen Hawking
"We know that brain cells fire in a predictable way before we move our bodies," Dr Itzhak Fried, of University of California, said. "We hypothesized that neurons would also react differently when we pronounce specific sounds. If so, we may one day be able to decode these unique patterns of activity in the brain and translate them into speech," Fried said.
"Once we understand the neuronal code underlying speech, we can work backwards from brain-cell activity to decipher speech. This suggests an exciting possibility for people who are physically unable to speak," said Fried.