On the Within-class Variation Issue in Alzheimer's Disease Detection
This work addresses the challenge of heterogeneity in Alzheimer's Disease classification for medical diagnosis, but it appears incremental as it builds on existing detection frameworks.
The paper tackles the problem of within-class variation in Alzheimer's Disease detection by proposing Soft Target Distillation and Instance-level Re-balancing methods, which improve detection performance on ADReSS and CU-MARVEL corpora.
Alzheimer's Disease (AD) detection employs machine learning classification models to distinguish between individuals with AD and those without. Different from conventional classification tasks, we identify within-class variation as a critical challenge in AD detection: individuals with AD exhibit a spectrum of cognitive impairments. Therefore, simplistic binary AD classification may overlook two crucial aspects: within-class heterogeneity and instance-level imbalance. In this work, we found using a sample score estimator can generate sample-specific soft scores aligning with cognitive scores. We subsequently propose two simple yet effective methods: Soft Target Distillation (SoTD) and Instance-level Re-balancing (InRe), targeting two problems respectively. Based on the ADReSS and CU-MARVEL corpora, we demonstrated and analyzed the advantages of the proposed approaches in detection performance. These findings provide insights for developing robust and reliable AD detection models.