The disclosure pertains to methods and compositions for treating disorders affecting the central nervous system (CNS). These disorders include neurometabolic disorders such as lysosomal storage diseases that affect the central nervous system, e.g., Niemann-Pick A disease. They also include disorders such as Alzheimer's disease. The disclosed methods involve contacting an axonal ending of a neuron with a composition containing high titer AAV carrying a therapeutic transgene so that the AAV vector is axonally transported in a retrograde fashion and transgene product is expressed distally to the administration site.