What does science say about ghosts?

Christine Simmonds-Moore, Ph.D., is a professor of psychology at the University of West Georgia who specializes in parapsychological research.

According to Simmonds-Moore, ghosts are found in every single culture and have been recorded throughout history.

“Ghosts come from experience,” she tells TODAY.com. “So, human beings have had experiences with spirits — and we can be neutral on whether some of those are genuine spirits, or whether they are explained more normally. But irrespective of that, people have had experiences because it’s a big part of being human.”

Whether those experiences are related to more earthly things like a near-death experience, loss of a loved one, or occur in an altered state such as a dream, deep relaxation or are chemically induced, in trying to understand them, they can change our perception or beliefs.

From there, those beliefs can lead to other experiences, including seeing ghosts. Bottom line? If you think there are ghosts, then you’re more inclined to think you’ve seen one.

“There’s a whole hierarchy of different types of ghost experiences,” Simmonds-Moore says, “and some of them are much more easy to explain using normal psychology than others.”

That said, Simmonds-Moore says that there are incidences in which people have paranormal encounters and inexplicably gain “access to information that they didn’t have access to” prior to those encounters. And those are somewhat less easy to explain.

Examples include things like people traveling to a location they’ve never been to, yet they “seem to know things what they shouldn’t know,” including events that occurred there or what a person they’ve never met was wearing, and other unexplainable circumstances.

“It doesn’t mean that it’s the media idea of a ghost, that there’s something persisting and haunting. It could be that it’s information that is tied to a place ,and some people who are in these different states are more able to notice that information and have access to than others,” she says.

According to Simmonds-Moore, some people believe they’ve had encounters with deceased loved ones, which is understandable given feelings of bereavement and loss, she says.

“But sometimes they might know that somebody’s going to pass before they do, or they might an encounter with an apparition, and they don’t know that the person has actually passed away and they see the apparition at the point of death and dying,” she says.

More than that, they might know how the person died even before the information has been relayed.

“I think that there are probably some extremely strong cases that are very rare, where you can’t always apply the normal explanation,” Simmonds-Moore says. “But the fact that they occur at all is interesting.”

So does all of this information make the case that ghosts are real?

“I think it’s probably more like information that has aspects of somebody’s life that might persist, and then other people might be able to access that field of consciousness," Simmonds-Moore says.

Whether they exist in the traditional sense or not, Simmonds-Moore says that there are many, very rare experiences that are difficult to explain.

In those cases, normal explanations don't necessarily fit.

"This implies that there are some experiences that are more intriguing, so there is a big question mark for those."

Science views ghosts as products of perception biases, hallucinations, or environmental factors. No empirical evidence supports the existence of supernatural entities. Ghostly encounters are often explained by psychology, neurology, and environmental influences rather than paranormal phenomena.

So does all of this information make the case that ghosts are real