The closest thing I have seen that may explain ghost encounters is that many ghost sightings that cannot be explained from physical things tend to be in places with a stronger magnetic field, and there is evidence that a small number of people are extremely sensitive to magnetic fields and can be affected by strong fields by seeing or hearing things that aren’t there, so it is possible that many ghost encounters are just people overly sensitive to magnetic fields hallucinating.

Such as with certain specific ghost, alien, or demonic encounters that can be explained by hallucinations during sleep paralysis.