For by Him were all things created, that are in heaven, and that are in earth, visible and invisible,...For the invisible things of Him from the creation of the world are clearly seen, being understood by the things that are made, ...so that THEY ARE WITHOUT EXCUSE: Col 1:16 / Rom.1:20

Saturday, August 17, 2024

Finely Detailed Cortical Organization of Semantic Representations

 I will praise Thee; for I am fearfully and wonderfully made:
marvellous are Thy works;
Psalm 139:14
"New techniques that can track brain activity down to a single neuron are now revealing exactly where this sound translation takes place within our minds.

"Humans possess an exceptional ability to extract nuanced meaning through language – when we listen to speech, we can comprehend the meanings of up to tens of thousands of words and do so seamlessly across remarkably diverse concepts and themes," says Harvard University neuroscientist Ziv Williams.

The recordings revealed words that share similar meanings like noodles and pizza create similar patterns of activity within participants' brains and that these patterns differ substantially when hearing words that have disparate meanings such as duck and coffee.

"We found that while 
--certain neurons preferentially activated when people heard words such as ran or jumped, which reflect actions, 
--other neurons preferentially activated when hearing words that have emotional connotations, such as happy or sad," explains Williams.

"
When looking at all of the neurons together, we could start building a detailed picture of how word meanings are represented in the brain."

What's more, the patterns of neuron activity in response to a word sound depends on what came before and after too.
"Rather than simply responding to words as fixed stored memory representations, these neurons seemed to adaptively represent word meanings in a context-dependent manner during natural speech processing," the team writes in their paper.
--This is what allows us to distinguish between homophones – words that sound the same but have different meanings like 'I' and 'eye'.

Together, these findings reveal a finely detailed cortical organization of semantic representations at the neuron scale in humans and begin to illuminate the cellular-level processing of meaning during language comprehension." 
ScienceAlert