The aim is to deliver pharmacologically-relevant molecules and nanoparticles that can modulate brain activity and physiologic states at the substructure level as well as to image these effects noninvasively and in real-time with functional magnetic resonance imaging (fMRI) and other methods. Focused ultrasound is employed to phase transition perfluorocarbon microdroplets into gas bubbles. We have shown that vaporization of 5 micron droplets, loadable up to 90% (v/v) with hydrophilic or lipophilic agents including nanoparticles, can be achieved readily in an approximately 3 mm3 volume through the adult rat skull. This delivery should aid transport through the blood brain barrier much as with ultrasound contrast agent cavitation. The methods should be scalable to delivery across the intact human skull in an ~4 mm diameter sphere throughout most of the brain with existing ultrasound transducer arrays and image guidance. Unprecedented localized treatments and studies of brain function could result from this start.