Researchers in the US have unveiled a non-invasive, drug- free approach to treating Alzheimer’s disease, based on flickering LEDs. Hannah Iaccarino of MIT and colleagues showed that levels of beta-amyloid plaque of the type associated with Alzheimer’s in mice are reduced by exposure to flickering LED light at frequencies of 40 Hz. This corresponds to the gamma-frequency range of brainwaves (25–80 Hz), which in normal brain function is associated with attention, perception and memory. One hour of exposure to the light reduced beta-amyloid plaque by an impressive 40–50%. Levels of abnormally modified Tau protein, also associated with Alzheimer’s disease, were also reduced. Other frequencies between 20 and 80 Hz were ineffective. Clinical trials with humans are now being planned.