Grammar acts as a biological compression tool that keeps the human brain from being overwhelmed by the uncertainty of language.
Analysis of twenty different languages shows that sentence structure exists primarily to reduce the mental load of processing information. Standard linguistics usually treats grammar as a set of arbitrary rules for decoration or clarity. This research reveals that grammar is actually a physical process mapped into specific neural pathways. People with schizophrenia and dementia lose this ability to compress meaning, making every word feel dangerously ambiguous. Language is less about sharing ideas and more about managing the sheer chaos of human thought.
The grip of grammar on meaning uncertainty: cross-linguistic evidence, neural correlates, and clinical relevance
arXiv · 2605.01537
Isolated word meanings are inherently uncertain. This uncertainty reduces when they are combined and anchored in context. We propose that grammar compresses meaning uncertainty cross-linguistically, which is reflected in brain and selectively disrupted in disorders. Compression was operationalized as the relative difference between non-contextual surprisal estimated from lexical frequency, and contextual surprisal from grammar-sensitive models. In narratives from 20 languages, contextual surpris