Beyond Transcription: Mechanistic Interpretability in ASR
Authors: name: Neta Glazer; name: Yael Segal-Feldman; name: Hilit Segev; name: Aviv Shamsian; name: Asaf Buchnick; name: Gill Hetz; name: Ethan Fetaya; name: Joseph Keshet; name: Aviv Navon
Published: 2025-08-21 15:42:53

Abstract: Interpretability methods have recently gained significant attention,
particularly in the context of large language models, enabling insights into
linguistic representations, error detection, and model behaviors such as
hallucinations and repetitions. However, these techniques remain underexplored
in automatic speech recognition (ASR), despite their potential to advance both
the performance and interpretability of ASR systems. In this work, we adapt and
systematically apply established interpretability methods such as logit lens,
linear probing, and activation patching, to examine how acoustic and semantic
information evolves across layers in ASR systems. Our experiments reveal
previously unknown internal dynamics, including specific encoder-decoder
interactions responsible for repetition hallucinations and semantic biases
encoded deep within acoustic representations. These insights demonstrate the
benefits of extending and applying interpretability techniques to speech
recognition, opening promising directions for future research on improving
model transparency and robustness.