Contrastive Graph Pooling for Explainable Classification of Brain Networks
This work addresses the problem of generating effective and explainable features for brain network classification in neurodegenerative diseases like Parkinson's, Alzheimer's, and Autism, representing an incremental improvement in domain-specific GNN design.
The paper tackled the challenge of tailoring graph neural networks (GNNs) for functional magnetic resonance imaging (fMRI) brain network analysis by proposing ContrastPool, a method with a contrastive dual-attention block and differentiable graph pooling, which demonstrated superiority over state-of-the-art baselines on 5 datasets across 3 diseases and provided explainable features matching neuroscience knowledge.
Functional magnetic resonance imaging (fMRI) is a commonly used technique to measure neural activation. Its application has been particularly important in identifying underlying neurodegenerative conditions such as Parkinson's, Alzheimer's, and Autism. Recent analysis of fMRI data models the brain as a graph and extracts features by graph neural networks (GNNs). However, the unique characteristics of fMRI data require a special design of GNN. Tailoring GNN to generate effective and domain-explainable features remains challenging. In this paper, we propose a contrastive dual-attention block and a differentiable graph pooling method called ContrastPool to better utilize GNN for brain networks, meeting fMRI-specific requirements. We apply our method to 5 resting-state fMRI brain network datasets of 3 diseases and demonstrate its superiority over state-of-the-art baselines. Our case study confirms that the patterns extracted by our method match the domain knowledge in neuroscience literature, and disclose direct and interesting insights. Our contributions underscore the potential of ContrastPool for advancing the understanding of brain networks and neurodegenerative conditions. The source code is available at https://github.com/AngusMonroe/ContrastPool.