- Scientists say they could one day decode the unique patterns of activity in the brain underlying speech
- They could potentially create a device that would communicate words as they were thought
Paralysis sufferers could learn to talk again after scientists discovered how the brain allows us to pronounce vowels, claims research.
Physicist Stephen Hawking, who suffers from motor neuron disease, is well known for relying on a computerised device to speak.
But the new research could pave the 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 – that housed 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.
The unravelling of vowels in the superior temporal gyrus reflected the anatomy that made speech possible – specifically the tongue’s position inside the mouth, the study says.
The research, published in Nature Communications was performed by Dr Ariel Tankus and Prof Shy Shoham who are both affiliated with the Technion, Israel Institute of Technology.
Dr Itzhak Fried, of the University of California Los Angeles, said: ‘We know that brain cells fire in a predictable way before we move our bodies.
‘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.
‘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.
‘In the future, we may be able to construct neuro-prosthetic devices or brain-machine interfaces that decode a person’s neuronal firing patterns and enable the person to communicate.’