Acoustocerebrography (ACG) is a medical test used to diagnose changes and problems in the brain and the central nervous system.[1] It allows for the noninvasive examination of the brain's cellular and molecular structure. It can also be applied as a means to diagnose and monitor intracranial pressure, for example as incorporated into continuous brain monitoring devices. ACG uses molecular acoustics,[2] in audible and ultrasound frequency ranges, to monitor changes. It may use microphones, accelerometers, and multifrequency ultrasonic transducers. It does not use any radiation and is completely free of any side effects. ACG also facilitates blood flow analysis as well as the detection of obstructions in cerebral blood flow (from cerebral embolism) or bleeding (from cerebral hemorrhage).