Perception of the supernatural and what science says about it
Even though different scientific methods have been employed to prove the nonexistence of ghosts, when it comes to the supernatural, a strong belief often trumps over science.
Take a recent incident at a village in Lopburi province, where people wholeheartedly believe that "krasue" exists even though it was revealed later that what they thought was the ghost was actually a chicken thief wearing the mask of an old woman with long greying hair and fangs for teeth.
Several scientists like Albert Einstein and the inventor Thomas Alva Edison introduced a variety of methods to test the existence of ghosts.
For instance, the first law of thermodynamics refers to the soul as a form of energy, an infrasonic and electromagnetic field that could have an impact on people's physical and mental health.
Even though those methods were later called "pseudoscience" due to lack of conclusive evidence, they are widely used among audiences of ghost-hunting TV shows.
There are many more hypotheses showing how and why people experience supernatural phenomena:
This condition arises when fear takes over people's minds, and gives them the illusion of being engaged with ghosts, and they could influence other people who do not believe in them.
Brandon Alvis, founder of the American Paranormal Research Association, said phasmophobia could enable people to see illusions, especially when living in scary places.
People with this symptom develop shortness of breath, unstable heart rhythm, sweating, nausea and vomiting, he said.
It is a condition that happens due to insufficient oxygen, which could disrupt people's sense and perception, and give rise to illusions.
This symptom causes seriously ill patients to experience supernatural phenomena or feel that their souls are leaving their bodies, said Alvis.
He added that people could develop cerebral anoxia while entering old or abandoned buildings with lots of fungi and toxins.
This is a condition in which the body is conscious but unable to move like it is possessed. It usually happens when people are half-asleep and half-awake.
Joe Nickell, a senior research fellow at the Committee for Sceptical Inquiry, a private agency that investigates supernatural phenomena with science, said sleep paralysis allows people to see fear in their hearts, such as deceased persons or aliens.
This symptom happens when your mind messes with you, he said, adding that it usually happens when people do not have enough sleep or live in lonely places.
Exposure to carbon monoxide
Carbon monoxide has been involved with haunted houses since the 1920s as it explains many of the occurrences there, such as feelings of being watched, hearing footsteps or voices, and seeing ghosts.
Exposure to this poisonous gas causes dizziness, nausea, shortness of breath, fatigue, and confusion as it does not have smell or colour. Some people could develop symptoms for years.