Skip to main content
. 2025 Sep 13;15(9):985. doi: 10.3390/brainsci15090985
Algorithm 1 Process of proposed NGRMTE model for reproducibility.
Input—Raw physiological signals (EEG, EMG, EOG)
Output—Detected sleep disorder class
Pre-processing
For each modality in (EEG, EMG, EOG)
  Segment signals into 30-s epochs
Feature Extraction
For each 30-s segment in each modality
  Extract time-domain features such as Mean, Standard deviation, Skewness, Kurtosis, and ZCR
Extract frequency-domain features using FFT, such as Spectral centroid, Spectral entropy, and Spectral band power using Equations (1)–(6).
Modality Embedding using 1D-CNN
For each modality
  Input extracted features into modality-specific 1D-CNN using Equation (7)
  Obtain modality-specific embeddings (fixed dimension)
Modality-wise Residual Gated Cross-Attention Fusion (MRGCAF)
For each modality pair (EEG-EOG, EEG-EMG, EOG-EMG)
  Compute cross-attention between modality embeddings
  Apply the forget gate to filter redundant or noisy interactions using Equations (8) and (9)
  Add a learnable residual path to preserve essential signal features
  Fuse actual modality and filtered cross-modality features using Equation (10)
Multi-Modal Transformer
  Stack fused features from all modality pairs
  Apply feed-forward networks
  Positional encoding
Classification
  Flatten transformer output
  Pass through linear layers with a learnable residual path using Equation (11)
  Apply SoftMax activation for multi-class classification using Equation (12)
  Use focal loss to address class imbalance using Equation (13)
  Optimize using the Adam optimizer
Return—Detected sleep disorder class for each epoch