Word meaning encoding across neurons (in humans)

Reading: Ultra-detailed brain map shows neurons that encode words’ meaning (Nature, news, 3 July 2024,) and the source article Semantic encoding during language comprehension at single-cell resolution (Jamali et al., Nature, same date).

Thank you to those ten people who allowed electrodes to be implanted into their brains during their epilepsy surgery!

When these people listened to sentences, some of their individual neuronal activity was recorded. After analysis, it looks like this:

It’s not “one brain cell encodes one word”. Some cells respond to one kind of thing (one “semantic domain”), some respond to two, and this varies by context. It’s the population of cells together than are encoding semantics of what you hear, in real time.

We’ve known for some time that neurons in the visual cortex can detect features, but I love that we now know there are neurons that respond to the meaning of words.