Automatic Speech Recognition for Child Reading: A Phonemic Approach using Isolated Words in Brazilian Portuguese

Aline N. Rodrigues, Carlos H. C. Ribeiro


Abstract
Automatic assessment of reading in children who are learning to read is challenging due to the lack of data and the high variability of children’s speech. This work investigates the improvement of Automatic Speech Recognition (ASR) models for the analysis of reading decoding of isolated words in Brazilian Portuguese. We propose a methodology based on fine-tuning Wav2Vec2.0 models, with a paradigm transformation from orthographic to phonemic transcription. Using a novel corpus of 5,400 audio word samples from children in the 2nd and 3rd grades of Elementary School, we compare pre-trained models in Portuguese and multilingual. Results reveal that the phonemic approach, combined with fine-tuning strategies, data augmentation, and adapted tokenization, significantly reduces the Phoneme Error Rate (PER). This overcomes the limitations of commercial tools and validates the use of ASR for the detailed diagnosis of decoding errors and phonological acquisition.
Anthology ID:
2026.propor-1.98
Volume:
Proceedings of the 17th International Conference on Computational Processing of Portuguese (PROPOR 2026) - Vol. 1
Month:
April
Year:
2026
Address:
Salvador, Brazil
Editors:
Marlo Souza, Iria de-Dios-Flores, Diana Santos, Larissa Freitas, Jackson Wilke da Cruz Souza, Eugénio Ribeiro
Venue:
PROPOR
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
974–979
Language:
URL:
https://aclanthology.org/2026.propor-1.98/
DOI:
Bibkey:
Cite (ACL):
Aline N. Rodrigues and Carlos H. C. Ribeiro. 2026. Automatic Speech Recognition for Child Reading: A Phonemic Approach using Isolated Words in Brazilian Portuguese. In Proceedings of the 17th International Conference on Computational Processing of Portuguese (PROPOR 2026) - Vol. 1, pages 974–979, Salvador, Brazil. Association for Computational Linguistics.
Cite (Informal):
Automatic Speech Recognition for Child Reading: A Phonemic Approach using Isolated Words in Brazilian Portuguese (Rodrigues & Ribeiro, PROPOR 2026)
Copy Citation:
PDF:
https://aclanthology.org/2026.propor-1.98.pdf