Masato Hasegawa is a Japanese neuroscientist and head of the Brain and Neuroscience Research Division at the Tokyo Metropolitan Institute of Medical Science. Hasegawa started to work on Alzheimer's disease in 1988, and became independent as head of the Division of Molecular Neurobiology at the Tokyo Metropolitan Institute of Psychiatry in 2001. He contributed to the identification of phosphorylated TDP-43 in FTLD and ALS in 2006, as well as the production of antibodies to phosph-TDP, and elucidation of the structure of TDP-43 in ALS brains. Hasegawa was awarded the Tokizane award 2022 and the Citation Laureate 2022.