You Do Not Fully Utilize Transformer’s Representation Capacity

Gleb Gerasimov, Yaroslav Aksenov, Nikita Balagansky, Viacheslav Sinii, Daniil Gavrilov


Abstract
In contrast to RNNs, which compress their history into a single hidden state, Transformers can attend to all past tokens directly. However, standard Transformers rely solely on the hidden state from the previous layer to represent the entire context. We show that this design creates pressure toward representation collapse and can degrade performance. To address this issue, we introduce Layer-Integrated Memory (LIMe), a lightweight extension that leverages existing key–value buffers and learns per-head, per-layer routing weights to integrate representations from previous layers. Across language modeling, synthetic reasoning, and deep architectures, LIMe improves perplexity per FLOP in the studied regimes and yields strong gains on synthetic tasks while preserving higher value-vector entropy and token separability. Finally, learned routing weights reveal systematic reuse of local and long-distance features, showing how LIMe enriches attention-time memory without increasing hidden-state size. Code is available at https://github.com/corl-team/lime.
Anthology ID:
2026.emnlp-main.2641
Volume:
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
EMNLP
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
60080–60100
Language:
URL:
https://aclanthology.org/2026.emnlp-main.2641/
DOI:
Bibkey:
Cite (ACL):
Gleb Gerasimov, Yaroslav Aksenov, Nikita Balagansky, Viacheslav Sinii, and Daniil Gavrilov. 2026. You Do Not Fully Utilize Transformer’s Representation Capacity. In Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing, pages 60080–60100, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
You Do Not Fully Utilize Transformer’s Representation Capacity (Gerasimov et al., EMNLP 2026)
Copy Citation:
PDF:
https://aclanthology.org/2026.emnlp-main.2641.pdf