Scientists use sound waves and tiny bubbles to temporarily open a gate in the brain’s protective barrier, letting the brain’s own cleanup crew remove harmful gunk called amyloid-beta plaques.

Scientists used a special sound wave treatment on mice with Alzheimer’s-like brain changes, and after four weekly sessions, they saw fewer and smaller clumps of harmful protein in the memory area of the brain—but the loose, floating version of that protein didn’t change much.