A Survey on Mechanistic Interpretability for Multi-Modal Foundation Models

Zihao Lin; Samyadeep Basu; Mohammad Beigi; Varun Manjunatha; Ryan A. Rossi; Zichao Wang; Yufan Zhou; Sriram Balasubramanian; Arman Zarei; Keivan Rezaei; Ying Shen; Barry Menglong Yao; Zhiyang Xu; Qin Liu; Yuxiang Zhang; Yan Sun; Shilong Liu; Li Shen; Hongxuan Li; Soheil Feizi; Lifu Huang

arXiv · 2502.17516

A Survey on Mechanistic Interpretability for Multi-Modal Foundation Models

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Abstract

The rise of foundation models has transformed machine learning research, prompting efforts to uncover their inner workings and develop more efficient and reliable applications for better control. While significant progress has been made in interpreting Large Language Models (LLMs), multimodal foundation models (MMFMs) - such as contrastive vision-language models, generative vision-language models, and text-to-image models - pose unique interpretability challenges beyond unimodal frameworks. Despite initial studies, a substantial gap remains between the interpretability of LLMs and MMFMs. This survey explores two key aspects: (1) the adaptation of LLM interpretability methods to multimodal models and (2) understanding the mechanistic differences between unimodal language models and crossmodal systems. By systematically reviewing current MMFM analysis techniques, we propose a structured taxonomy of interpretability methods, compare insights across unimodal and multimodal architectures, and highlight critical research gaps.

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Zihao Lin, Samyadeep Basu, Mohammad Beigi, Varun Manjunatha, Ryan A. Rossi, Zichao Wang, Yufan Zhou, Sriram Balasubramanian, Arman Zarei, Keivan Rezaei, Ying Shen, Barry Menglong Yao, Zhiyang Xu, Qin Liu, Yuxiang Zhang, Yan Sun, Shilong Liu, Li Shen, Hongxuan Li, Soheil Feizi, Lifu Huang. 2025-02-22. A Survey on Mechanistic Interpretability for Multi-Modal Foundation Models. https://arxiv.org/abs/2502.17516

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