How to “Read” the Brain Signals Underlying Human Speech

Recommendable! This research has the potential to rewrite textbooks!


"“We’ve laid the groundwork for synthesizing speech from neural activity,” "

"There’s an idea that’s literally in textbooks that certain regions along the motor cortex strip relate to different parts of the body. High up on the head, you’ve got the leg, and lower down, you have voice.
Stavisky: The canonical textbook picture is of a human body draped over the brain.
Shenoy: It’s called the homunculus. It dates back over 70 years and has become indoctrinated – Sergey directly questioned it. He said maybe a brain area for the hand and arm is also related to speech."

"[the researchers] wondered if the hand knob brain area [of the motor cortex] might be active during more than just attempted hand and arm movements. Previous studies, for example, had hinted that the neural circuits for manual gestures might be interlinked with those for speech. ...

[researcher] recorded neural activity when participants repeated short words like “beet” and “seal.” The words sparked different brain activity patterns, his team found. ... could then “read” the patterns to decipher which words or syllables had been spoken.

“We’ve found that this part of the brain is active when moving your tongue, mouth, and face,” ... There’s some evidence in the literature that there’s a close relationship between our neural circuits for hand gestures and speech gestures – movement of the tongue, the lips, the jaw ... 

We know very little about speech because, until now, we’ve had very little access to it at single-neuron resolution. People have studied speech using other methods – like ECoG [electrocorticography], where electrodes are placed on the surface of the brain. But that averages together the activity of thousands of neurons. Our study is the first time activity from over a hundred electrodes – each recording from one or just a handful of individual cells from motor areas of the brain – has been studied in relation to producing speech. That’s the key distinction. ... The participants in this study have tetraplegia caused by spinal cord injury – they can’t use their arms or legs – but they can still talk."

How to “Read” the Brain Signals Underlying Human Speech | HHMI.org: Scientists have discovered that a brain region that controls hand and arm movement also offers a window into studying speech. The work brings researchers a step closer to building medical devices that help people who cannot speak.