Reading Without a Reader: Large Language Models Collapse Reading and Writing into a Single Entangled Code

תקציר מקורי באנגליתarXiv:2607.24797v1 Announce Type: cross Abstract: In the literate human brain, reading and writing are two doubly-dissociable systems: a ventral decoding route (impaired in pure alexia) and a fronto-parietal encoding route (impaired in pure agraphia), sharing a partial orthographic core. A decoder-only large language model (LLM) instead drives both from a single autoregressive path optimized on text, a recent cultural invention rather than an evolved instinct. We ask how entangled that one mechanism is, comparing an input-side "reading code" $W_E$ with an output-side "writing code" $W_U$ via an entanglement index $E \in [0,1]$ (CKA, Procrustes residual, mutual $k$-NN) calibrated against an independent-init floor and a tied ceiling. Across nine probes on GPT-2, OPT, Pythia (14M--1.4B), T5,