Automatic speech recognition (ASR) for pathological speech remains underexplored, especially for Huntington's disease (HD), where irregular timing, unstable phonation, and articulatory distortion challenge current models. We present a systematic HD-ASR study using a high-fidelity clinical speech corpus not previously used for end-to-end ASR training. We compare multiple ASR families under a unified evaluation, analyzing WER as well as substitution, deletion, and insertion patterns. HD speech induces architecture-specific error regimes, with Parakeet-TDT outperforming encoder-decoder and CTC baselines. HD-specific adaptation reduces WER from 6.99% to 4.95% and we also propose a method for using biomarker-based auxiliary supervision and analyze how error behavior is reshaped in severity-dependent ways rather than uniformly improving WER. We open-source all code and models.
Figures & tables
Figure 1: Overview of our adapter-based HD-ASR framework. A frozen Parakeet-TDT encoder is augmented with trainable PEFT adapters. Standard ASR supervision is retained, while a masked mean-pooled encoder representation is used to predict one auxiliary biomarker family per run (prosody, phonation, or articulation).
Model
Architecture Family
Parameters
WER (%)
Whisper-small
Encoder-decoder
244M
19.78
Whisper-medium
Encoder-decoder
769M
26.91
Whisper-large-v2
Encoder-decoder
1.55B
18.44
Parakeet-TDT 0.6B
TDT / Transducer
600M
6.99
Meta Omnilingual 300M
CTC
300M
30.46
Table 1: Zero-shot ASR performance across model families on the HD test set. Results are reported on 47 scored test utterances.
Model
Substitution Share (%)
Deletion Share (%)
Insertion Share (%)
Whisper-small
17.99
9.35
72.66
Whisper-medium
13.29
6.68
80.04
Whisper-large-v2
16.56
9.18
74.27
Parakeet-TDT 0.6B
41.90
29.68
28.43
Meta Omnilingual 300M
43.30
22.85
33.85
Table 2: Error composition across zero-shot ASR baselines on HD speech. Values are reported as percentages of each model’s total errors (S+D+I) .
Model
WER (%)
Substitutions (%)
Deletions (%)
Insertions (%)
Parakeet-HD
4.95
2.09
1.29
1.57
Parakeet-HD-Prosody
6.11
2.13
2.53
1.45
Parakeet-HD-Phonation
6.07
1.92
2.77
1.38
Parakeet-HD-Articulation
6.44
1.94
3.21
1.29
Table 3: ASR performance for biomarker-auxiliary Parakeet variants.
Model
Stage
Δ WER
Δ Sub.
Δ Del.
Δ Ins.
Parakeet-HD-Prosody
Control
-0.26
-0.05
+0.16
-0.37
Parakeet-HD-Prosody
Pre-HD
-0.22
-0.11
+0.00
-0.11
Parakeet-HD-Prosody
Prodromal
-0.24
+0.00
-0.24
+0.00
Parakeet-HD-Prosody
Manifest
+3.59
+0.19
+3.35
+0.05
Parakeet-HD-Phonation
Control
-0.05
-0.16
+0.37
-0.26
Parakeet-HD-Phonation
Pre-HD
-0.11
+0.00
+0.00
-0.11
Table 4: Cohort-level change relative to Parakeet-HD for biomarker-auxiliary variants. Values are percentage-point differences; negative is better. Best Δ WER in each cohort is bolded.
End-to-end Automatic Speech Recognition (ASR) systems hallucinate on natural speech, yet existing mitigation methods are typically evaluated on non-speech or artificially corrupted audio. We introduce HALAS, the first human-annotated dataset of naturally occurring hallucinations from seven state-of-the-art ASR models on real unprocessed earnings call recordings. HALAS provides span-level labels, enabling analysis of hallucination patterns and their severity. Our analysis reveals strong cross-model vocabulary overlap and confirms that hallucinations also occur for almost correctly transcribed speech (characterized by a low Word Error Rate). The proposed benchmark with HALAS shows that the character and semantic-level metrics used as a proxy for hallucination detection reach 81% ROC-AUC, while state-of-the-art detection methods achieve an F1 score of only 53.1%. As such, HALAS establishes the first rigorous non-artificial benchmark for the detection and mitigation of ASR hallucinations.
Mateusz Barański, Jan Jasiński, Julitta Bartolewska +2
Signal Processing Group, Institute of Electronics, AGH University of Krakow, Poland
Automatic speech recognition (ASR) has advanced remarkably for standard speech, yet speech affected by neurological conditions remains a challenge. We present S-DiverSe (Spanish Diverse Speech), a corpus of 3.2 hours of in-the-wild Spanish speech from 22 speakers with amyotrophic lateral sclerosis, Parkinson's disease, and stroke. The dataset contains 444 manually transcribed audio segments with metadata on speaker sex, disease type, and intelligibility. S-DiverSe is designed to support ASR evaluation and development for neurologically affected Spanish speech. We describe the dataset, analyze its composition, and report baseline ASR results alongside initial adaptation experiments. Our findings reveal that heuristic text post-processing is more robust than fine-tuning for out-of-domain neurological Spanish speech. This underscores the need for dedicated in-the-wild Spanish benchmarks.
Fernando López, Fernando Ibañez, Ana Martínez +4
Scientific Research, Telefónica Innovación Digital, Spain · Universidad Autónoma de Madrid, Spain · Brno University of Technology, Czech Republic
Automatic speech recognition (ASR) systems often perform poorly in dysarthric speech, limiting their usefulness to affected speakers in everyday communication. This paper presents a personalized ASR system for a dysarthric speaker, built by adapting a foundation ASR model to speaker-specific data. Using the TEQST tool, we collected 92 hours of read speech and later added 8.8 hours of user corrections gathered through a deployed mobile application. Starting from Whisper, fine-tuning reduced word error rate to 15.8% with only 1.4 hours of adaptation data, reached 10.7% with 22.5 hours, and achieved the best result of 9.7% when using all available data including the corrections. Using LoRA adaptation and/or Qwen3-ASR as foundation model performed worse in this setting. The results show that personalized fine-tuning can make foundation ASR models substantially more effective for dysarthric speech and suitable for practical deployment.
Christian Huber, Laura Kernahan, Alexander Waibel
Interactive Systems Lab Karlsruhe Institute of Technology Karlsruhe, Germany · Interactive Systems Lab Carnegie Mellon University Pittsburgh PA, USA