Horror movie trailers often use infrasound frequencies that human ears cannot consciously detect but will absolutely cause physical feelings of anxiety.

A closer look

Horror movie trailers often use infrasound frequencies that human ears cannot consciously detect but will absolutely cause physical feelings of anxiety. These extremely low-frequency bass tones trick your primitive lizard brain into thinking there is a massive earthquake or a dangerous predator nearby, triggering a completely involuntary flight or fight response. The terrifying dread you feel while watching a two-minute advertisement for a supernatural slasher film is literally just audio engineers manipulating your biological survival instincts for corporate profit. It is essentially legal psychological warfare deployed in the middle of a crowded multiplex, ensuring that you will buy a ticket just to figure out why a simple thirty-second commercial about a haunted porcelain doll made your stomach drop into your shoes