: Chills down the spine, "shivering on the wrist," and an "odd feeling in the stomach". The "Ghost Frequency" (18.9 Hz)
: Tandy’s research showed that standing waves at this frequency can cause a sensation of chest pressure and a "feeling of a presence" in the room. Mechanism of Anxiety Induction
: Sudden feelings of sorrow, intense anxiety, and "nervous feelings of revulsion or fear".
: Scientists from the National Physical Laboratory used a 7-meter pipe to generate the tone, playing it during specific pieces without the audience's knowledge.
The study of infrasound and anxiety often references the work of , who identified 18.9 Hz (very close to 17 Hz) as a frequency capable of causing "hauntings".