Diego, CA. (5/5/00)- Did the dog really eat that student's homework?
New research presented at the annual meeting of the American Academy of Neurology
suggests we often miss obvious facial clues that might help distinguish fact
Researchers from the University of Oklahoma Health Sciences Center presented
a study indicating that most people focus on the lower part of the face when
dealing with others. Yet the person's true feelings were far more likely to
be 'telegraphed' through the upper face.
"Perhaps the old adage 'the eyes are the windows to the soul' may be correct,"
said Calin Prodan, MD, a neurology resident at the University of Oklahoma
Health Sciences Center in Oklahoma City and lead author of the study.
"Humans learn in early childhood to manipulate facial emotions to make them
appropriate to a given social situation which, in time, allows them to engage
in deceitful behavior," said Prodan. "For example, a person who is angry with
their superior may display a 'social' smile rather than an angry scowl when
asking for a raise."
The Oklahoma researchers are studying the ways in which the brain recognizes
nd processes facial emotion. They conducted study in which 30 volunteers were
briefly shown line drawings of a human face displaying different emotions
on the upper versus lower face. Depicted emotions included happiness, sadness,
anger, fear, surprise and neutrality. The volunteers were asked to view the
drawings in either their right or left visual fields. This allowed the researchers
to evaluate which side of the brain was processing the information contained
in the illustrations.
The study participants were far more likely to identify the more easily
simulated lower face emotions, regardless of visual field. When asked to focus
on the upper face, they did so best when the pictures were shown to their
left visual field (processed by the right side of the brain). However, most
continued to identify the lower facial emotion when viewing in their right
visual field (processed by the brain's left side).
"Recognition of emotional displays on the lower face appear to be processed
by the brain's left hemisphere as part of the social -- or learned -- emotional
system, whereas emotional displays on the upper face appear to be processed
by the brain's right hemisphere as part of the primary -- or inborn -- emotional
system," said Prodan. "These findings help us to gain a better understanding
of the neurologic basis for affective communication, which will increase a
physician's ability to assess how diseases, such as stroke and dementia, alter
People may naturally focus on the lower face to aid in speech comprehension
during conversation, especially in noisy environments. Social conventions
may also play a role as many cultures consider it unacceptable to look someone
directly in the eye -- the "evil eye" belief. This may be interpreted as aggressive
or threatening behavior, similar to those observed in some animal species.
"There is a natural learning curve starting in early childhood for acquiring
the skills to read facial displays of emotion," Prodan said. "We certainly
can train ourselves to pay more attention to upper facial displays, which
can help us read a person's true emotional state. However, this can have a
downside because of social conventions."
Professional interrogators such as FBI investigators have known for some
time that people who are lying tend to exhibit numerous physical and verbal
cues. Neurologists and psychiatrists have only recently begun to devise methods
that might help measure these cues objectively.