Ghosts and the paranormal, explained
Hauntings, poltergeists — and the surprising science of why we feel them.
Belief in ghosts is one of the oldest and most widespread of human ideas. People across every culture report the sense of a presence, cold spots, footsteps and figures. Whatever their ultimate cause, these experiences are real to those who have them — and science has learned a lot about why they happen.
Hauntings and poltergeists
A 'haunting' usually means repeated strange experiences tied to a place; a 'poltergeist' (German for 'noisy ghost') traditionally involves noises and objects seeming to move. Investigators have found that many classic cases trace back to draughts, settling buildings, pipes, pets, or, occasionally, deliberate pranks.
Why we feel a presence
Researchers have identified several ordinary triggers for 'paranormal' feelings. Sleep paralysis can produce a vivid sense of an intruder in the room. Very low-frequency sound (infrasound), below the range of hearing, can cause unease and shivers. Carbon-monoxide poisoning can cause hallucinations. And our brains are wired to see faces and patterns — pareidolia — even where none exist.
How we treat these stories
We report ghost stories as stories — the experience, the setting, the folklore — without asserting that a spirit caused them. Where a natural explanation is known, we say so. It takes nothing away from a good ghost story to understand where the chill really comes from.