Parapsychology is a controversial form of science, involving the study of paranormal event events in the psychic sciences. It can be, for instance:
  • Near-death experiences
  • Clairvoyance (”clear sight or clear view”), and related events
  • Telepathy
  • Reincarnation
  • Precognition
The studies were formally studied by the philosopher Max Dessior in the 1880'ies. The biggest capacity in the parapsychology would still be the American J. B. Rhine.

The parapsychology fights against the demand, that events must be recreatable at any time, if just the setup of the experiment is rebuild.
As many of there phenomena are spontaneous, it is not possible to replicate under laboratory conditions. Even though many attempts are made.  Therefore many scientist view this subject to pseudo-science.

The parapsychology is only investigating subjects about the psyche of man. So, a parapsychologist does not investigate UFO-sightings.
A parapsychologist does not necessarily investigate ghost- or poltergeist-activity. It depends on the scientist's view on the subject: Is a ghost part of the psyche or not?

If these paranormal phenomenon are something different than the psyche, it is more correct to call the person “paranormal investigator”. Or "Phenomenologist", if the team tries to describe the phenomena with knowledge from other scientific areas.