An experimental, non-invasive approach that aims focused sound waves through the skull, switched on and off forty times a second, to strengthen the brain's fast rhythms, clear sticky plaques, and calm inflammation as the brain ages. Direct proof comes almost entirely from mice; it has never been tested in people, and benefits in healthy adults remain unproven. (Full Review)
| Marker | Target | Why |
|---|---|---|
| EEG 40 Hz gamma response | Robust, reproducible 40 Hz steady-state response | Confirms the brain is actually entraining to the stimulation |
| Cognitive composite (e.g., MoCA) | 26–30 (MoCA) | Tracks memory and thinking over time |
| Plasma p-tau217 | Low / stable (assay-specific) | Blood marker tracking Alzheimer's-type pathology |
| Plasma Aβ42/40 ratio | Higher / stable (assay-specific) | Reflects amyloid-β burden |
| Neurofilament light (NfL) | Low for age (assay-specific) | General marker of nerve-cell injury |
| hs-CRP | < 1.0 mg/L | Tracks systemic inflammation |
| Homocysteine | < 7–8 µmol/L | Elevated levels are linked to brain atrophy |
| Vitamin D (25-OH) | 40–60 ng/mL | Supports brain and immune health |
Cadence: Baseline, then reassess at ~4–8 weeks after starting a course, and every 6–12 months thereafter; brain-rhythm and cognitive checks around each course.