Organizations: Speech and Hearing Research Center, School of Intelligence Science and Technology and the Center for BioMed-X Research, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China · Speech and Hearing Research Center, School of Intelligence Science and Technology, Peking University, Beijing, China, and also with the National Key Laboratory of General Artificial Intelligence, Beijing, China · Center for BioMed-X Research, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
Decoding perceived speech from non-invasive brain recordings has garnered significant attention in recent years due to its wide range of potential applications. However, existing methods face considerable challenges in cross-subject decoding, primarily due to limited generalizability and the absence of explicit mechanisms for extracting subject-consistent information. These limitations result in high training costs and suboptimal decoding performance. To address these challenges, we propose an innovative Cross-Subject Perceived Speech Decoding (CPSD) framework, which comprises two training stages: source model pre-training and personal specialization. In the source model pre-training stage, contrastive learning is employed to capture shared representations across multiple source subjects. Subsequently, personal specialization initializes the model for the target subject by extracting consistent components from the source model and fine-tuning it using target subject data. Additionally, we introduce the Positional Encoding-based Spatial Attention (PESA) module, which remaps MEG/EEG data into a standardized reference space, thereby enhancing cross-subject consistency and facilitating model training. We evaluate the proposed CPSD framework on three perceived speech neural datasets encompassing different modalities and languages. The results demonstrate that our framework outperforms baseline methods by more than 6.8%, 15.4%, and 15.8% in Top-10 accuracy on the Armeni 2022, PKUEEG 2025, and Broderick 2018 datasets, respectively. Further analyses confirm the effectiveness, efficiency, and robustness of the proposed approach.
Figures & tables
Fig. 1: Different settings for perceived speech decoding include: (a) intra-subject decoding, which involves decoding exclusively within the target subject; multi-subject decoding, where the model is trained on data from all subjects simultaneously and then evaluated on the target subject; and (b) cross-subject decoding, which entails pre-training the model on source subjects followed by generalization and evaluation on the target subject.
Fig. 2: Illustration of the CPSD framework. (a) During the source model pre-training stage, the model output is aligned with the wav2vec representation. (b) In the personal specialization stage, the subject layer for the target subject is first initialized, and then the representation from the MEG/EEG data of the target subject is realigned with the corresponding wav2vec representation.
Fig. 3: Motivation for the PESA module. Different shapes within the large circle represent the MEG/EEG features of subjects under various stimuli.
Dataset
Language
Modality
Sensors
Sampling rate
Subjects
Folds for CV
Duration
Test samples
Armeni 2022
English
MEG
275
1200
3
3
30.0 h
1024
PKUEEG 2025
Chinese
EEG
64
1000
25
25
68.1 h
128
Broderick 2018
English
EEG
128
512
19
19
19.2 h
128
TABLE I: A brief description of the neural datasets related to speech perception. The test samples indicate the size of the retrieval set for each sample.
Armeni 2022
PKUEEG 2025
Broderick 2018
Methods
Top-10(%)
Rankacc(%)
Top-10(%)
Rankacc(%)
Top-10(%)
Rankacc(%)
Random
1.3 ± 0.4
50.6 ± 0.5
7.3 ± 1.2
49.4 ± 2.2
7.6 ± 1.6
50.8 ± 0.3
ATM-S [ 33 ]
4.2 ± 1.4
68.8 ± 4.8
9.2 ± 3.2
52.7 ± 2.1
9.0 ± 2.8
51.9 ± 3.3
iTransformer [ 38 ]
15.0 ± 12.3
76.6 ± 16.4
11.5 ± 3.5
56.3 ± 3.1
9.3 ± 2.9
52.1 ± 3.3
VLAAI [ 1 ]
14.7 ± 13.2
75.0 ± 19.4
14.6 ± 12.4
55.9 ± 11.3
10.5 ± 4.9
55.5 ± 6.5
Brainmagic [ 14 ]
17.4 ± 13.8
83.1 ± 7.7
20.8 ± 8.1
65.7 ± 7.0
17.7 ± 7.1
63.0 ± 5.5
TABLE II: Perceived speech decoding results across various datasets. We averaged the decoding results across different subjects and evaluated the robustness of performance improvements using statistical tests.
Armeni 2022
PKUEEG 2025
Broderick 2018
Top-10(%)
Rankacc(%)
Top-10(%)
Rankacc(%)
Top-10(%)
Rankacc(%)
Base
17.4 ± 13.8
83.1 ± 7.7
20.8 ± 8.1
65.7 ± 7.0
17.7 ± 7.1
63.0 ± 5.5
Base+PESA
25.7 ± 25.5
84.7 ± 9.8
27.7 ± 8.5
70.7 ± 5.7
18.1 ± 8.3
62.6 ± 6.9
Base+PS
50.3 ± 12.8
95.1 ± 2.2
29.2 ± 10.9
72.2 ± 6.3
35.3 ± 11.8
75.2 ± 7.0
Base+PESA+PS
61.3 ± 12.4
96.9 ± 1.5
43.0 ± 13.6
80.0 ± 6.7
39.9 ± 15.3
77.7 ± 8.0
TABLE III: Ablation study of the CPSD framework across different datasets. (PS stands for personal specialization.)
Armeni 2022
PKUEEG 2025
Broderick 2018
Methods
Latent
Final
Latent
Final
Latent
Final
Brainmagic
0.011 ± 0.001
0.230 ± 0.012
0.003 ± 0.001
0.093 ± 0.022
0.001 ± 0.001
0.157 ± 0.009
CPSD(Ours)
0.016 ± 0.002
0.274 ± 0.012
0.002 ± 0.001
0.129 ± 0.010
0.002 ± 0.001
0.227 ± 0.010
TABLE IV: Evaluation of neural representation consistency.
Fig. 4: The correlation between model performance and neural representation consistency ( corr=0.66 , p<0.001 ).
Fig. 5: Training times under different settings.
Fig. 6: Zero-shot decoding performance across various perceived speech datasets.
Fig. 7: Decoding results using various hyperparameters on the Broderick 2018 dataset. The triangles in the box plot indicate the mean values.
Armeni 2022
PKUEEG 2025
Broderick 2018
Methods
Top-10(%)
Rankacc(%)
Top-10(%)
Rankacc(%)
Top-10(%)
Rankacc(%)
Brainmagic
17.4 ± 13.8
83.1 ± 7.7
20.8 ± 8.1
65.7 ± 7.0
17.7 ± 7.1
63.0 ± 5.5
Brainmagic-MD
52.7 ± 15.5
95.6 ± 2.1
39.1 ± 10.3
78.8 ± 5.3
39.2 ± 12.4
77.4 ± 7.1
CPSD
61.3 ± 12.4
96.9 ± 1.5
43.0 ± 13.6
80.0 ± 6.7
39.9 ± 15.3
77.7 ± 8.0
CPSD-MD
63.0 ± 11.8
97.1 ± 1.3
45.5 ± 11.5
81.5 ± 5.5
46.0 ± 14.5
81.0 ± 6.6
TABLE V: Comparison with Multi-Subject Settings. (MD stands for Multi-Subject Decoding.)
Fig. 8: Verification of the validity of sensor locations as input. The performance improvement of CPSD compared to the Shuffle setting in both figures is statistically significant ( p<0.01 ).
Fig. 9: Visualization of channel weights from the PESA module across various datasets.
School of Intelligence Science and Technology, Peking University, Beijing, China · Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China · National Key Laboratory of General Artificial Intelligence, Beijing, China
HiTZ Center, University of the Basque Country – UPV/EHU, Spain · Basque Center on Cognition, Brain and Language – BCBL, Spain · Laboratory of Functional Anatomy, Faculty of Human Motor Sciences, Université libre de Bruxelles (ULB), Belgium +3