' Elizabeth A. Towne and Christopher K. Murphy weren't thinking about ghosts when they moved with their two young children into their circa-1790 house in Upton in 1996. To the contrary, both Ms. Towne and Mr. Murphy are scientists. Ms. Towne's background is in immunology and Mr. Murphy has a Ph.D. in microbiology and works in the biotechnology field.

But after years of unexplained events occurring in their home, and an encounter last fall with a paranormal investigator making a presentation at Stone's Public House in Ashland, the family thought it might be interesting to see if there was

any documentable evidence of haunting.

"The first I heard about our house's (reputation) was when the neighbors moved in and said, `I guess your house is haunted.' They had talked about it with the town clerk," Ms. Towne said. "I was kind of intrigued and thought it was funny. Weird things happen in old houses."

Weird things had been happening since the family moved in. "The kids had always said there was something upstairs," Ms. Towne said, explaining that the children's bedrooms were in the house's renovated former attic.

Their daughter, Samantha, now 16, had frequently complained, as a child, that there was an unfamiliar little boy bothering her in her bedroom. But when she'd point to where she had seen him, there was nothing there.

Samantha also clearly remembers seeing a man in an old military uniform going through her sock drawer, according to Ms. Towne.

Their son, Ian, now 13, wouldn't sleep in his own bedroom. Ms. Towne said she went upstairs to help him get to sleep one night, several years ago.

"As soon as we lay down I had this really weird feeling, a pressure," she said, demonstrating hands on her upper chest. "I distinctly heard `grrrrr,' like an exasperated sigh. Ian heard it too and asked what it was," she said.

Ms. Towne has heard unusual pounding on a wall. She's heard sounds like somebody choking or crying, when no one else was in the house. She saw the latched attic door swing open so violently that it slammed shut. A visiting relative heard approaching footsteps in a basement room, but no one was there.

"I'm really skeptical, but a little open-minded," Ms. Towne said about the possibility that their house was haunted. "Several times a year something odd happens that nobody can explain."

Mr. Murphy maintains a skeptical stance. He said, "It's not that I'm not open to it; I'm a scientist and need different levels of evidence."

The opportunity to collect hard data came last December when Ms. Towne and Mr. Murphy invited David F. Francis Jr. and his team of two paranormal investigators - the preferred term for ghost hunters - to study their home while the family was away for the holidays.

Mr. Francis, an Upton resident, works in the auto-shipping field but has investigated potential paranormal activity at a dozen or so homes, inns and libraries, including the Charlemont Inn in the Berkshires, the Millicent Library in Fairhaven and Stone's Public House, where he conducts ongoing research.

Popular television shows like "Ghost Hunters" have raised awareness of paranormal investigation, although Mr. Francis said he prefers a less flashy, more methodical approach.

"I don't like using all those meters you see on TV; they're so easy to trip and manufacture evidence," Mr. Francis said. "Face it: Paranormal investigation is boring.

"We approach it as scientifically as we can. What the family has been able to offer is almost a controlled environment," he said.

Mr. Francis first checked out the background of the house with the Upton Historical Society.

The structure, known as the Palmer Wood House, is considered to date back to around 1790, according to a structural architect who worked with the family, although the Historical Society estimates it as being from around 1830.

It had been a minister's home and is thought to have served as a tavern and trolley repair facility at various times. An addition was built in the 1950s.

With the family away, Mr. Francis and his co-investigators brought in two home surveillance cameras with infrared imaging, which they set up in the upstairs bedroom area and the basement playroom.

They connected the cameras to DVD recorders and ran them for eight hours a night, continuing after everyone left the house. Each investigator had a digital audio recorder to capture electronic voice phenomena, or EVP.

Mr. Francis said that he's never heard with his ears a response to a question he's asked during an investigation, such as "What year is this?" but he has heard distinct responses on EVP recordings at Stone's Public House.

The investigators recorded the house under various light conditions, adjusting window shades that might cause shadows, and recorded normal baseline sounds such as pipes clanging and wood creaking.

They tested for drafts that might cause objects to move. They even compared ambient noise and call logs from the nearby police and fire stations to see whether transmissions from those facilities might cause interference.

"As far as video, we didn't get anything the first few nights," Mr. Francis said.

"We shifted the cameras to Samantha's room - she had seen the door handle lift up." Here he captured something minute, but to his eye, noteworthy: Two round paper lanterns hanging from the ceiling started rotating.

Mr. Francis ran the recording at different speeds and noticed they moved independently, in opposite and then synchronized rotations.

"I can't say it's a sign of a haunt, but I can't explain it," Mr. Francis said.

The audio recordings detected sounds in the basement that weren't similar to the house's usual background noise.

In the last 10 minutes of a recording, a noise sounds like a female shouting. There's a loud boom, like something slamming on a tabletop. Then the recorder inexplicably shut off, even though it had been set to run for another two-and-a-half hours.

At a later date, Ms. Towne detected what sounds like a male whispering after she left a recorder running upstairs.

"I won't say they're EVPs - they're anomalies," Mr. Francis said. "We won't say it's proof until we get the same results over and over again."

Mr. Francis explained that there are two types of hauntings. Paranormal investigators call "intelligent hauntings" those in which intelligent response or purposeful actions are observed - the poltergeists that rearrange the china cabinet, for instance.

Then there's "residual hauntings," which pick up and relay random events such as a radio broadcast from the 1930s. "If I were to venture, that's what I'd say is here," Mr. Francis said.

Mr. Francis won't say definitively that the family's house is haunted, but he's got findings that he'd like to confirm.

And as paranormal investigators gather more evidence, developments in scientific theory may move toward an explanation for it all.

For example, string theory, a mathematical model of theoretical physics, suggests the possibility that the universe comprises up to 10 dimensions, instead of the four recognized dimensions of height, width, length and time. The theory excites Mr. Francis.

He said, "It's going to take some serious science to figure this out. Right now, it's so fringe that no one's going to be looking seriously at it."

"It has to be something someone can repeat independently," Mr. Murphy said. "I think it's intriguing. If you put serious effort to figure out what it is, maybe you get something you can hang your hat on."

The family isn't perturbed by their house's mysterious occurrences. "You either take it with a sense of humor or you scream," said Ms. Towne.