A residual connection creates a shortcut around one or more neural-network layers, combining earlier node information with transformed neighborhood information. In graph neural networks, it preserves node features, improves gradient flow, and helps prevent over-smoothing as message passing becomes deeper. section 11.6 section 11.6.4
In a GNN update, a residual connection can:
- Preserve access to original node features while incorporating aggregated neighbor features. section 11.6.4
- Provide additional backpropagation paths that support deeper architectures. section 11.6
- Reduce feature homogenization caused by repeated message passing. section 11.6
GraphSAGE-style update
Concatenate each node’s current features with its aggregated neighbor features, transform the combined vector with a linear layer, and apply ReLU. This preserves both information sources for the next representation.











