Did your mother ever tell you to stop making
a funny face because it might "freeze"
that way? Well, in a way, she was right. New
research shows that facial expressions may
be "frozen" by your genes.
Comparing the expressions of blind people
to other family members, Israeli researchers
discovered there's probably a genetic component
to facial expressions and that human faces
may be programmed from the start to look,
and act, the same as those of their parents
and siblings.
"There is evidence for a hereditary
basis for facial expressions," said the
study's lead author, Gili Peleg, a doctoral
candidate at the University of Haifa in
Israel. "This study paves the
way for discovering genes that influence facial
expressions, understanding their evolutionary
significance, and elucidating repair mechanisms
for syndromes characterized by lack of facial
expression, such as autism," the researcher
said.
"This is an interesting study that raises
yet another question about those qualities
that we have thought of as having a purely
emotional basis," commented Dr. Charles
Goodstein, a psychoanalyst and professor of
psychiatry at New York University Medical
Center. "Many more qualities may be based
on physiology and genetics than we've realized."
He said that having families share similar
facial expressions might perform some evolutionary
function. "If you have the genetically
linked capacity to emulate the facial expressions
of your parents, in terms of evolution, you'd
probably be the most likely to survive,"
he said. "There's evolutionary value
to having similar facial expressions; you
may be more likely to gain the care, love
and attention of your parents."
Results of the study were published in this
week's issue of the Proceedings of the
National Academy of
Sciences.
Peleg, under the supervision of professors
Eviatar Nevo and Gadi Katzir at the International
Graduate Center of Evolution at the University
of Haifa, compared the facial expressions
of 21 people who were blind from birth to
the expressions of 30 of their relatives.
The facial expressions of congenitally blind
people could not have been influenced by their
environment, the researchers pointed out,
since they remain visually unaware of their
relatives' faces.
Each study volunteer was interviewed individually
and all experienced sadness, anger and joy
at some point during the interview. Facial
expressions were photographed and indexed.
In most cases, families did exhibit a unique
family facial expression "signature,"
according to the researchers. In fact, in
about 80 percent of cases, family members
could be accurately linked to individual participants,
based on their range of facial expressions.
"We found that the frequency of a facial
movement of a congenitally blind subject in
his family is significantly higher than that
outside his family," said Peleg.
"There will always be debate about what
traits are nature vs. nurture," said
Goodstein. "This study eliminates an
important consideration, however: What could
have been envisioned by the child."
Environment could still play a role in the
development of facial expressions, even in
blind children, he added. Goodstein theorized
that when a child first smiles, a parent might
recognize the expression and be pleased by
it.
"What if the parent rewards the baby's
smile and pats the baby? That smile is more
likely to become a habitual smile," noted
Goodstein.
"Facial expressions may be hardwired
at birth, but they may not," he added.
