If mum is happy and
you know it, wave your fetal arms
New Scientist,
Marec 2010, by Jessica
Hamzelou
FOOD and oxygen pass easily from mother
to fetus. Now it seems that fleeting sadness
or happiness is also transmitted to an
unborn baby.
Stress or depression in pregnancy can harm a
fetus, but less is known about the effect of
transient emotions. To investigate, Kazuyuki
Shinohara and colleagues at Nagasaki
University in Japan showed 10 pregnant
volunteers a cheery 5-minute clip from the
musical The Sound of Music. Another 14
watched a tear-jerking 5 minutes from The
Champ. Each clip was sandwiched between two
"neutral" samples so that the team could
measure any changes in fetal movements
against a baseline.
The women listened to the films through
headphones to ensure that only the effect of
their emotions, not the sounds, were being
measured. "Fetuses can hear by the last
trimester," says Shinohara.
The team counted the number of arm, leg and
whole body movements via ultrasound and
found that during the happy film clip the
fetuses moved their arms significantly more
than when the pregnant women watched a
neutral clip. Meanwhile, the fetuses of sad
women moved their arms less (The Journal of
Physiological Sciences, DOI:
10.1007/s12576-010-0087-x).
What makes the fetuses of happy mothers wave
isn't clear. However, such movement is an
indicator of a working nervous,
cardiovascular and musculoskeletal system,
says Alexander Heazell at the University of
Manchester, UK. He says the study offers us
insight into how external influences affect
fetuses.
Shinohara suggests that sadness releases
more of the "fight or flight" hormone, which
redirects blood away from the uterus. The
fetus diverts the reduced blood supply to
its brain and heart and away from its limbs.
But Janet DiPietro of the Johns Hopkins
Bloomberg School of Public Health says it's
too early to use the study to advise women.
Fetal Recall
? Memory in Utero
Fetuses demonstrate a primitive form of
memory
New
Scientist, January 2010, by Karen Springen
When does memory begin? We
can’t consciously call up images from our
infancy, but we surely learn important,
lasting associations at very early ages. New
work suggests this type of memory begins
even in the womb.
In a study published in July in Child
Development, researchers from the
Netherlands reported short-term memory in
30- to 38-week-old fetuses. First they put a
vibrating, honking device on the abdomens of
93 pregnant women. The fetuses quickly
“habituated”—that is, they figured out that
the noise was not dangerous. When they heard
it again 10 minutes later, they did not
squirm and their heart rates did not
escalate. “It’s like getting used to a New
York train station,” says lead author J. G.
Nijhuis, a professor of obstetrics at
Maastricht University in the Netherlands.
“It is a learning capability to distinguish
safe from unsafe stimuli. It is a primitive
form of memory.”
The 34-week-old fetuses even recalled the
sound four weeks later. “What this study
clearly says is at least beginning at 30
weeks and possibly before that, the fetal
brain is starting to lay down short-term
memories and might even be laying down some
long-term memories,” says Rahil Briggs,
director of Healthy Steps at Montefiore
Medical Center and assistant professor of
pediatrics at Albert Einstein College of
Medicine. “This is a sensitive period of
development.”
Fetuses habituate in other ways, too.
Substance-abusing moms give birth to
drug-addicted babies. A study found that the
babies of mothers who watch a popular
Spanish-language soap opera while pregnant
calm down when they hear the show’s theme
music. And anecdotally, some dads who read
to fetuses in the womb think their babies
are born recognizing their voices, says
pediatrician Tanya Remer Altmann, a
spokesperson for the American Academy of
Pediatrics.
The bottom line: be conscientious around the
baby-to-be. “The environment in utero, and
extra utero, is very important,” says
pediatrician Dimitri Christakis, director of
the Center for Child Health, Behavior and
Development at Seattle Children’s Hospital.
After all, the brain triples in size in the
first two years of life. And perhaps even
younger fetuses develop memories—researchers
will investigate that possibility next.
Early Scents
Really Do Get 'Etched' In The Brain
Science Daily,
November 2009
Common experience tells us that
particular scents of childhood can leave
quite an impression, for better or for
worse. Now, researchers reporting the
results of a brain imaging study online on
November 5th in Current Biology, a Cell
Press publication, show that first scents
really do enjoy a "privileged" status in the
brain.
"We found that the first pairing or
association between an object and a smell
had a distinct signature in the brain," even
in adults, said Yaara Yeshurun of the
Weizmann Institute of Science in Israel.
"This 'etching' of initial odor memories in
the brain was equal for good and bad smells,
yet was unique to odor." Sounds did not have
the same effect, the research showed.
In the study, the researchers presented
adults with a visual object together with
one, and later with a second, set of
pleasant and unpleasant odors and sounds
while their brains were imaged by functional
magnetic resonance imaging (fMRI). A week
later, the researchers presented the same
objects inside the fMRI and tested
participants' associations of those images
with the scents and smells.
The researchers found that people remembered
early associations more clearly when they
were unpleasant, regardless of whether they
were smelled or heard. The images, however,
revealed a unique activation in particular
brain regions in the case of their first
olfactory (but not auditory) associations.
That signature held regardless of whether
the odors or sounds were pleasant or
unpleasant. The researchers even found that
they could predict what a person would
remember later based on the activity in
their brains on day 1.
Yeshurun explained that it makes good sense
to remember unpleasant memories as a kind of
evolutionary "risk management." But the
findings show that there is also something
particularly special about early memories of
smells.
That wasn't really unexpected, Yeshurun said
-- it is after all a phenomenon that has
long fascinated authors, poets, and
scientists alike. Still, the results did
hold some surprises.
"We expected a unique representation of
initial or 'first' olfactory associations
but did not expect that it would materialize
even in cases where the behavioral evidence
did not indicate a stronger memory,"
Yeshurun said. "In our paradigm, initial and
later olfactory associations were remembered
equally well, but only first associations
had the unique brain representation."
In terms of understanding the brain, the
findings suggest that activity in two brain
regions, known as the hippocampus and
amygdala, together can render a memory
"special."
Although any application of the findings
would be far off, Yeshurun said the results
could suggest ways to strengthen particular
memories. "Perhaps more importantly, it may
help us generate methods to better forget
early and powerful memories, such as
trauma," she said.
The researchers include Yaara Yeshurun,
Hadas Lapid, Yadin Dudai, and Noam Sobel, of
the Weizmann Institute of Science, in
Rehovot, Israel.
When Do
Dreams Begin ?
Science Daily,
April 2009, by
Christie Nicholson
Recent research from the American
Institute of Physics has found that the our
dreaming sleep begins much earlier than
previously thought.
Why we dream continues to elude us.
Scientists have proven we need to dream.
When robbed of their dreams, rats die within
four weeks. We also know that at seven
months a fetus is dreaming, its muscles and
eye movements giving the tell-tale signs of
REM (or rapid eye movement) sleep and
non-REM sleep. But what happens before seven
months? When do our dreams begin?
Research published in Chaos, a journal of
The American Institute of Physics, provides
the first attempt at an answer.
Mathematicians analyzed the brainwaves of a
fetal sheep in utero, at 15-weeks. The brain
signals at that stage are quite complex, set
against noise that is difficult to dampen.
But using sophisticated mathematics,
scientists discerned a pattern of cortical
activation and deactivation, cycling every
five to ten minutes — this, the scientists
note, is a crude precursor to the longer
cycles of REM and non-REM sleep.
We can only guess at the content—do sheep
dream of electric androids? But the study
shows that dreamlike sleep develops before
rapid eye movements. And the discovery may
give researchers new insight into the
purpose of sleep and dreams.