Divergent Longitudinal Propagation of White Matter Degradation in Logopenic and Semantic Variants of Primary Progressive Aphasia. Tu S, Leyton CE, Hodges JR, Piguet O, Hornberger M J Alzheimers Dis. 2016; 49(3):853-61. PMID: 26484929. Abstract Comment Bookmark Recommend Follow Comment | Bookmark | Recommend | Follow