We studied the effect of high frequency hypersonic inaudible sound on brain activity in young middle-aged people and cognitively normal elderly people using PET and EEG. The participants were average 36.8 years of age SD ± 7.7 years of age (27 years old to 48 years old), 3 males, 5 females, is healthy volunteers of a total of eight people and mean age 77.6 years old SD ± 4.1 years (72 years to 88 years), 5 males, 10 females, is the healthy elderly of a total of 15 people. The sound stimulation to young middle-aged people and elderly people was shown to activate their brainstems and increase the α wave in the occipital lobe,