A Multi-Scale Feature and Dual Self-Attention Mechanism for Enhanced Alzheimer’s Disease Classification

Magnetic resonance imaging (MRI) technology shows significant potential in predicting early pathological changes associated with Alzheimer's disease (AD). However, the complexity of MRI and their multidimensional characteristics pose challenges in model classification tasks, and single-scale features often fail to capture subtle changes in lesion areas effectively. To improve the accuracy of AD predictions, we propose a network model based on multi-scale features and a dual self-attention mechanism (MSDA). This model integrates depthwise separable convolutions with an improved self-attention mechanism, thereby enhancing the classification ability for AD. First, MRI undergo head motion correction, image alignment, and skull stripping to enhance the model's capability to extract features related to AD lesions. Second, we designed a multi-scale convolutional network structure that utilizes depthwise separable convolution kernels of varying sizes, allowing the network to effectively capture multi-scale feature information from MRI and accurately identify lesion areas. Finally, we introduced a dual self-attention module, which includes channel self-attention and spatial self-attention, further augmenting the model's ability to extract lesion features by learning the differences in features across different categories of MRI in both channel and spatial dimensions. Experimental results indicate that the MSDA network model demonstrates exceptional performance in classifying normal controls (NC) and AD within the ADNI dataset, outperforming existing models in classification accuracy, performance, and generalization capability. The accuracy, sensitivity, and specificity of the model reached 97.8%, 96.3%, and 99.4%, respectively.