A vectorial code for semantics in human hippocampus

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 23, 2025

ABSTRACT As we listen to speech, our brains actively compute the meaning of individual words. Inspired by success large language models (LLMs), hypothesized that brain employs vectorial coding principles, such is reflected in distributed activity single neurons. We recorded responses hundreds neurons human hippocampus, which has a well-established role semantic coding, while participants listened narrative speech. find encoding contextual word simultaneous whose selectivities span multiple unrelated categories. Like embedding vectors models, distance between neural population correlates with distance; however, this effect was only observed (like BERT) and reversed non-contextual Word2Vec), suggesting depends critically on contextualization. Moreover, for subset highly semantically similar words, even embedders showed an inverse correlation distances; attribute pattern noise-mitigating benefits contrastive coding. Finally, further support critical context, range covaries lexical polysemy. Ultimately, these results hypothesis hippocampus follows principles.

Language: Английский

Power and reproducibility in the external validation of brain-phenotype predictions

Nature Human Behaviour, Journal Year: 2024, Volume and Issue: 8(10), P. 2018 - 2033

Published: July 31, 2024

Language: Английский