summary: Researchers have made a breakthrough about how the human brain forms words before we speak them. Using Neuropixels probes, they uncovered how neurons represent and assemble sounds into language.
This research not only reveals the complex cognitive stages involved in speech production, but also opens up possibilities for the treatment of speech and language disorders. This technology could lead to prosthetics for synthetic speech, potentially benefiting people with neurological disorders.
Important facts:
- This study uses advanced Neuropixels probes to record neuron activity in the brain to show how we think and produce words.
- Researchers have discovered neurons specialized for both speaking and listening, revealing separate brain functions for language production and comprehension.
- The discovery could help develop treatments for speech and language disorders and lead to brain-machine interfaces for synthetic speech.
sauce: Harvard University
A new study led by researchers at Harvard Massachusetts General Hospital uses advanced brain recording techniques to understand how neurons in the human brain work together and what words we say. It has been demonstrated that children can think and vocalize their thoughts.
The findings provide a detailed map of how sounds such as consonants and vowels are represented in the brain long before they are uttered, and how they are linked during language production. Offers.
The works published in Naturewhich could lead to improved understanding and treatment of language disorders.
“Speaking usually seems easy, but our brains go through a lot of effort to produce natural speech, including coming up with the words we want to say, planning articulatory movements, and producing the intended utterance. perform complex cognitive steps,” said senior author Jib Williams. Associate Professor of Neurosurgery at MGH and Harvard Medical School.
“Our brains perform these feats incredibly quickly, at around three words per second in natural speech, with surprisingly few errors. But how exactly do we perform these feats? Whether this will be achieved remains a mystery.”
Using a cutting-edge technology called a neuropixel probe to record the activity of single neurons in the prefrontal cortex, the frontal region of the human brain, Williams and his colleagues found that it is involved in language production and that language production ability identified cells that may underlie the talk. They also discovered that the brain has separate groups of neurons specialized for speaking and listening.
“The use of Neuropixels probes in humans was first pioneered at MGH,” Williams said. “These probes are remarkable; despite being smaller than the width of a human hair, they also have hundreds of channels that can record the activity of dozens or even hundreds of individual neurons simultaneously.”
Williams worked to develop the recording technology in collaboration with MGH and Sidney Cash, a professor of neurology at Harvard Medical School who also helped lead the research.
This research explores how neurons represent some of the most fundamental elements involved in the construction of spoken language, from simple sounds called phonemes to collections into more complex strings of letters such as syllables. It shows whether there are any.
For example, producing the word dog requires the consonant “da” produced by touching the tongue to the hard palate behind the teeth. By recording individual neurons, the researchers found that specific neurons activated before this phoneme was spoken out loud. Other neurons reflect more complex aspects of word construction, such as the specific assembly of phonemes into syllables.
The researchers showed that their technique could reliably determine the sounds an individual makes before they speak. In other words, scientists can predict what combinations of consonants and vowels will be produced before the word is actually spoken. This capability could be used to build prosthetics and brain-machine interfaces that can generate synthetic speech, potentially benefiting a variety of patients.
“Disruptions in speech and language networks are observed in a variety of neurological disorders, including stroke, traumatic brain injury, tumors, neurodegenerative disorders, neurodevelopmental disorders, and more,” said Williams Institute Postdoctoral Fellow and lead author of the study. Co-author.
“Our hope is that a deeper understanding of the fundamental neural circuits that enable speech and language will pave the way to developing treatments for these disorders.”
The researchers are expanding their research by studying more complex language processes, including how people choose the words they say and how the brain assembles words to convey an individual’s thoughts and feelings. I would like to be able to investigate questions about how to write texts that can be communicated to others. .
About this language phonetic research news
author: MGH Communications
sauce: Harvard University
contact: MGH Communications – Harvard University
image: Image credited to Neuroscience News
Original research: Open access.
“Single neuron components of human speech production” by Jib Williams et al. Nature
abstract
Single neuron components of human speech production
Humans can generate a wide variety of combinations of articulatory movements to produce meaningful speech. This ability to adjust specific speech sequences and their syllabification and inflection on his subsecond timescale allows us to generate thousands of word sounds and is a core element of language. . However, the basic cellular units and structures by which we plan and generate words during speech remain largely unknown.
Now, using acute, ultra-dense neuropixel recordings that can sample entire cortical columns in humans, we have encoded detailed information about the phonetic sequence and organization of words planned during natural speech production, controlling language. discovered neurons in the prefrontal cortex.
These neurons represented a specific order and structure of prespeech articulatory events and reflected the division of the speech sequence into individual syllables. They also accurately predicted the phonetic, syllabic, and morphological components of upcoming words, demonstrating temporally ordered dynamics.
Collectively, we show how a mixture of these cells is broadly organized along cortical columns and how their activity patterns shift from joint planning to production. We also show how these cells reliably track the detailed organization of consonants and vowels during perception, and specifically how they distinguish between processes associated with speaking and those associated with listening.
Taken together, these findings reveal a strikingly structured organization and coding cascade of speech representation by human prefrontal neurons and demonstrate cellular processes that can support speech production.
