Mitigating Confounding in Speech-Based Dementia Detection through Weight Masking

Zhecheng Sheng, Xiruo Ding, Brian Hur, Changye Li, Trevor Cohen, Serguei V. S. Pakhomov


Abstract
Deep transformer models have been used to detect linguistic anomalies in patient transcripts for early Alzheimer’s disease (AD) screening. While pre-trained neural language models (LMs) fine-tuned on AD transcripts perform well, little research has explored the effects of the gender of the speakers represented by these transcripts. This work addresses gender confounding in dementia detection and proposes two methods: the Extended Confounding Filter and the Dual Filter, which isolate and ablate weights associated with gender. We evaluate these methods on dementia datasets with first-person narratives from patients with cognitive impairment and healthy controls. Our results show transformer models tend to overfit to training data distributions. Disrupting gender-related weights results in a deconfounded dementia classifier, with the trade-off of slightly reduced dementia detection performance.
Anthology ID:
2025.acl-long.514
Volume:
Proceedings of the 63rd Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Month:
July
Year:
2025
Address:
Vienna, Austria
Editors:
Wanxiang Che, Joyce Nabende, Ekaterina Shutova, Mohammad Taher Pilehvar
Venue:
ACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
10419–10434
Language:
URL:
https://preview.aclanthology.org/ingestion-acl-25/2025.acl-long.514/
DOI:
Bibkey:
Cite (ACL):
Zhecheng Sheng, Xiruo Ding, Brian Hur, Changye Li, Trevor Cohen, and Serguei V. S. Pakhomov. 2025. Mitigating Confounding in Speech-Based Dementia Detection through Weight Masking. In Proceedings of the 63rd Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers), pages 10419–10434, Vienna, Austria. Association for Computational Linguistics.
Cite (Informal):
Mitigating Confounding in Speech-Based Dementia Detection through Weight Masking (Sheng et al., ACL 2025)
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PDF:
https://preview.aclanthology.org/ingestion-acl-25/2025.acl-long.514.pdf