Blinks, Winks and Nods Reveal Infants Do Learn at an
Early Age
By Emil Venere

Scientist Marie Balaban is using sophisticated laboratory
techniques that measure how babies respond to everyday
stimuli like facial expressions and changes in a musical
melody.
    One fact is apparent: infants develop cognitive skills
at an astonishingly young age.
    Dr. Balaban, an assistant professor in the Psychology
Department, specializes in early perceptual and cognitive
development. In addition to observing infant behavior, she
studies the subtle, yet telling physiological reactions that
reveal how infants perceive and understand their
environment.
    The developmental psychologist uses "unobtrusive"
methods to probe the workings of the infant mind. "In other
words, measures that can be obtained while you're sitting
here talking to me," she said.
    For example, the babies are outfitted with headphones
for research on how they perceive changes in melody. In
another study, their blink reflex is monitored with sensors
attached to their cheeks as they are shown photographs of
angry, neutral and happy faces.
    "We can't ask the infant, do they know that an angry
face is negative," said Dr. Balaban, who arrived at Hopkins
in August after working five years at Harvard University.
    She has spent much of the summer and fall setting up
her laboratory. In addition to the usual scientific gear,
her lab has a few uncustomary features: a waiting room
equipped with suitable toys and a table for changing
diapers, another room with a one-way mirror that enables
researchers to make inconspicuous observations.
    While babies cannot communicate verbally, their
physiological reactions are often similar to those of
adults. By studying those reactions, scientists can draw
inferences about the things infants perceive.
    Research reveals that something happens early in the
development of infant brains that enables babies to
understand the difference between anger and joy.
    Dr. Balaban and researchers in her laboratory show the
babies a series of faces depicting anger, joy or neutrality.
The infants are monitored for their "startle reflex," which
is triggered by producing a brief, unexpected sound while
the babies are looking at pictures. Then the scientists
record the eye-blink response to the sound.
    The strategy is to draw parallels between how adults
and infants respond physiologically when looking at an angry
face, compared with a happy face.
    "Even if you hardly move at all, you will blink," said
Dr. Bala-ban, who recently received a two-year grant from
the National Institute of Mental Health to further her
research.
    "If you are looking at a picture that is negative in
terms of its affective component, then your reflex response
to, say, an unexpected sound is heightened during that
negative theme," she said. "Whereas, if you are looking at a
positive picture your reflex response to that same kind of
sound is reduced.
    "Our evidence seems to show that by five months they
are showing some kind of physiological discrimination," Dr.
Balaban said.
    She also is studying how the infant brain recognizes
changes in melody. Scientists know that, in certain types of
perceptual tasks, the right side of the brain is best at
recognizing an overall outline, such as the relation of the
features on a face, or the general structure of a melody.
The left side specializes more in analysis, or picking out
smaller pieces of the puzzle.
    One of her recent studies strives to determine how an
infant perceives change in melody, specifically, whether the
brain's left hemisphere is better at detecting minute
changes in notes and intervals and whether the right
hemisphere is best at perceiving alterations to the overall
melody.
    "We know that they can detect changes in melody fairly
early, probably around five months," Dr. Balaban said. She
studies older infants--between eight and nine months--to
determine how they distinguish change in melody.
    The right ear sends more information to the brain's
left hemisphere, and the left ear sends more information to
the right hemisphere. By placing headphones on the infants,
Dr. Balaban said, researchers can study the brain's
perception of melody change.
     "We vary it so that sometimes the melody changes only
in the left ear, and sometimes it's only in the right ear,"
she said. Preliminary findings show that infants use the
right hemisphere more for perceiving the overall contour of
the melody.
    Between 24 to 36 babies will enroll in the studies,
said Dr. Balaban, who located the infants by looking up
birth records in newspapers and sending query letters to the
parents. She also took out ads in publications specializing
in baby care.
    Parents are a vital component in the research. They
generally are not paid but sometimes receive a small travel
reimbursement or stipend. 
    "One of the reasons we know as much as we do is because
parents bring their babies in," Dr. Balaban said.
    Heather Jackson is one of those parents. Shortly after
receiving a letter from the Hopkins researcher, Jackson
brought her son Joshua to the lab, where he was enrolled in
the melody study.
     "He's my baby and I watch him, but I really don't sit
there and study how he learns," said the Hanover woman, a
secretary in the engineering and fabrication branch at the
Applied Physics Laboratory.
    "Even though they explained it to me over the phone, it
was very different than what I had imagined," she said. "I
thought it was very interesting."