Researcher

Hitomi Yanaka

Hitomi Yanaka researches language reasoning and explainable AI. Her early papers used natural-deduction proofs to compare sentence meanings and find corresponding phrases. Later shared work tested systematic inference in neural language models, including the SyGNS testbed and Japanese entailment evaluation. Papers from 2024 and 2025 examined language-specific neurons and Transformer behavior during compositional generalization. She directs RIKEN’s Explainable AI Team as of October 2026.

Works
109
Citations
288
h-index
8

Publication numbers from OpenAlex, as of 14 October 2026.

Photo of Hitomi Yanaka

Timeline

  1. 2017–2018

    Reasoning with formal proofs

    Yanaka coauthored research that used natural-deduction proofs to measure sentence meaning and find corresponding phrases. These papers connected formal reasoning methods with practical language tasks.

  2. 2020–2022

    Testing systematic language understanding

    With collaborators, she studied whether neural models learn rules for language inference. The group introduced the SyGNS testbed in 2021 and published a Japanese textual-entailment and similarity evaluation in 2022. The work gave researchers concrete tasks for testing how models generalize.

  3. 2024–2025

    Examining model internals

    Yanaka coauthored research on language-specific neurons in multilingual models in 2024 and the internal operations of Transformers in compositional generalization in 2025. These studies connected outward behavior with mechanisms inside the model.

  4. As of October 2026

    Explainable AI at RIKEN

    Yanaka directs RIKEN’s Explainable AI Team. The team studies how AI acquires meaning and performs inference, with the aim of providing explanations that help people make decisions. Its program draws on both humanities and science.

Sources and credits

Photo: www.riken.jp; creator not stated. License: Not stated by source. Source: riken.jp. Cropped to a square and resized. Ask us to remove or replace this photo.

  1. RIKEN AIP: Hitomi Yanaka riken.jp. Checked 13 October 2026.
  2. RIKEN AIP: Organization riken.jp. Checked 13 October 2026.