Voxel-Based Brain-Behavior Mapping in Neurodegenerative Diseases

Over the last decades, sophisticated neuroimaging techniques have become a key methodology in defining brain areas affected by progressive illnesses, helping the identification of syndrome-specific anatomic patterns and/or the resulting changes in cognitive function and behavior. This chapter provides a review of the contemporary research on neurodegenerative diseases, spanning a variety of different clinical and brain atrophy patterns, along with the methodologies that helped to uncover them. We start by outlining the brain-behavior mapping method commonly used, followed by a direct comparison of automated techniques of brain morphometry, voxel- versus surface-based. We then present the results of seminal studies applying these techniques to investigate clinical group differences or brain-language relationships. These studies have improved our ability to identify clinical symptoms and perform differential diagnoses and greatly deepened our understanding of the neurobiology of language. We conclude by highlighting how, thanks to these methodological advances, the field can now tackle unresolved anatomical-functional questions embracing clinical neurodegenerative data.