In 1999, Glen Lord's 4-year-old son died from complications of a
tonsillectomy. Not long after that, Mr. Lord began having dreams in
which Noah, his son, had grown into a healthy young man.

Mr. Lord felt comforted by these "visits." But in 2002, he had a dream
in which Noah introduced him to two boys. "He explained that he had to
go, but these boys would be staying with me," recalls Mr. Lord. "When I
woke up, I told my wife that I knew I'd never dream about him again. And
I haven't."

Mr. Lord, who runs a manufacturing firm in Nashua, N.H., believes that
final dream was a reassurance from Noah that he was OK, and that there
were other children who needed to be loved. In late 2002, Mr. Lord and
his wife adopted two brothers through a Russian adoption program.

Every night, millions of people are visited by deceased loved ones. In
dreams, the living and the dead embrace, converse and reach
understandings. What are we to make of these encounters? Are they merely
emotional responses to dreamers' grief? Or, as research suggests, are
there patterns to these dreams that could explain the inexplicable?

I met Mr. Lord last month in Dearborn, Mich., at the annual conference
of the Compassionate Friends, a support group for parents whose children
have died. About 1,100 parents attended, and the sessions on dreams and
"after-death communication," or ADC, were standing room only.

Attendees learned that basic "grief dreams" tend to be fragmented and
filled with symbolism. There are often common themes, such as travel:
Dreamers get off an airplane or train, and their late loved ones travel
on without them.

"Visitation dreams," on the other hand, are usually more vivid, with
less need for interpretation. In these dreams, those who died of serious
illnesses are often healthy; if they were in a wheelchair, they can
walk. These dreams can feel "sacred" to those who've had them, says Bill
Guggenheim, a co-founder of the ADC Project, an independent research
group.

Women are more open to potential messages in dreams, while men may
underreport dream experiences, researchers say. Mr. Guggenheim theorizes
that men fear being perceived as weird or too grief-stricken. "They
wonder what friends and bosses will think of them," he says.

In U.S. surveys, about 60% of women and 40% of men say they've dreamed
about late loved ones, says Kelly Bulkeley, former president of the
International Association for the Study of Dreams, and a visiting
scholar at the Graduate Theological Union in Berkeley, Calif.

Humans have been chronicling visitation dreams since the days of
prehistoric cave paintings, and many cultures today embrace the concept.
Americans, however, are more inhibited, researchers say. Our lifestyles
-- shortened sleep patterns, late-night TV viewing, alarm clocks --
limit opportunities for the deep-sleep dreaming that leads to dream
recall. And a lot of us discount anything that can't be proven by
science. "The scientific skeptical tradition in the U.S. says that
dreams are random nonsense," says Dr. Bulkeley.

This is a "tragedy," because people who have these dreams feel
belittled, says Jeffrey Long, an oncologist who founded the After Death
Communication Research Foundation. He has collected testimonies from
more than 1,000 people. His Web site, adcrf.org, allows the bereaved to
share dream experiences.

Brain-imaging research suggests that the prefrontal cortex -- the part
of the brain engaged in rational thinking -- basically goes offline when
we sleep. The parts of the brain that then become active are more
engaged in imagination and emotions, which could explain visitation
dreams.

Many people were grateful to discuss their dreams at the Compassionate
Friends conference. I sat in the audience, surrounded by parents who
lost children. I had put my cellphone on vibrate, and two of my kids
kept calling. (Nothing important, it turned out.) Normally, I'd be
annoyed; the kids knew I was working. But on that day, I felt blessed.
All around me, people spoke of how they yearned to go to bed at night,
in the hope they'd be contacted by their kids again.

The session was led by Carla Blowey of Montrose, Colo. In 1991, her
5-year-old son, Kevin, was hit by a truck while riding his bike. He died
in Ms. Blowey's arms.

Since then, she has kept a dream journal, and she finds the process
healing. Dreams of Kevin have been a respite from the grief of her
waking hours, and even painful dreams have brought clarity. Once she
dreamed of entering a house and seeing Kevin on the stairs, crying
because he'd been left alone. She sat on the stairs and comforted him.

She asked the attendees for words conjured up by the dream. They called
out: "guilt," "love," "helpless." She told them her interpretation: This
was the house of death, and she should have died first, so Kevin
wouldn't be alone there. The dream allowed her to recognize how heavily
this weighed on her.

Some at the session said they were unable to dream about loved ones.
Sarah Brummel, a 26-year-old attendee from Santa Cruz, Calif., offered
advice. Since her brother, Gregory, died in his sleep in 2003, she has
been dreaming about him easily. Her mother, however, longed to dream
about Gregory but couldn't. Ms. Brummel encouraged her mom to stop
watching TV before bed and instead spend a few moments in quiet
reflection. "After that, dreams started coming," Ms. Brummel said.

Researchers can't say whether such dreams are visitations or merely
"expressions of our deepest wishes," says Dr. Bulkeley. "It's an
unanswerable debate."

But as Ms. Blowey told that crowded room of grieving parents, a dream
about a late loved one is often a gift. "Don't overanalyze it. Accept it
with gratitude."

Write to Jeffrey Zaslow at