Abstract: Methods and compositions for treating neurodegenerative diseases are provided. In one embodiment, the method includes administering gangliosides into the brain of a mammal in need of such treatment. The gangliosiges are preferably GM1 and GD3 gangliosides. The gangliosides are intranasally administered in an amount effective to delay and/or prevent disease progression, and to increase the resilience of brains by promoting adult neurogenesis by gangliosides.