Sushane Dulloo
Author directory2026
TextNCA: Neural Cellular Automata for Language Modeling via Hierarchical Local Attention
Avni Mittal | Avinash Anand | Ashutosh Kumar | Dikshant Kukreja | Kritarth Prasad | Sushane Dulloo | Erik Cambria | Timothy Liu | Zhengkui Wang | Rajiv Ratn Shah
Findings of the Association for Computational Linguistics: EMNLP 2026
Avni Mittal | Avinash Anand | Ashutosh Kumar | Dikshant Kukreja | Kritarth Prasad | Sushane Dulloo | Erik Cambria | Timothy Liu | Zhengkui Wang | Rajiv Ratn Shah
Findings of the Association for Computational Linguistics: EMNLP 2026
Neural Cellular Automata (NCAs) generate complex spatial patterns in vision by repeatedly applying a shared local rule to persistent cell states, combining local perception, weight-shared iteration, and gated in-place updates. We test this principle in language modelling with TextNCA, a 1D causal model in which token positions act as cells, windowed attention provides local perception, and a GRU-style gate updates their states. Its hierarchical variant cascades increasingly wide attention windows w ∈ 8,32,128 and reuses each stage’s parameters for T_s iterations. We train roughly 30M-parameter models on SlimPajama for 60k steps and evaluate on WikiText-103. TextNCA trails a similarly sized Transformer-6L (60.3 versus 52.8 best-run PPL), so we study it as an analytical probe rather than a performance alternative. Reordering or flattening the windows raises PPL by 16.7–70.8, whereas a non-iterating sliding-window Transformer preserving the staged order performs comparably across three seeds. These results identify the narrow-to-wide schedule as the dominant factor and provide no reliable evidence that iterated weight sharing improves perplexity at this scale. Intermediate-state analyses support a prepare-then-decode account in which early stages reorganise representations and the final wide stage performs most next-token loss reduction.