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Organization on Fetal Alcohol Syndrome
page on FAS
Despite warnings, some women still drink alcohol while pregnant, and each year
thousands of babies are born brain damaged.
As this ScienCentral News video reports, new research suggests there may be
Your baby's brain on drugs
The amount brain damage that results from a mother drinking during pregnancy
can vary. But the most
severe cases can lead to much smaller brains and profound loss of structures
within. In fact, alcohol is the most damaging of any substance during pregnancy.
“The effects of cocaine do not appear to be as devastating as the effects
of alcohol,” says Ann Streissguth, director of the Fetal
Alcohol and Drug Unit at University of Washingtonâ€™s School of Medicine.
“Itâ€™s generally considered that alcohol is the most severe and
has more impact on the developing fetus in the life of the offspring than
any of the other drugs that have been studied. And thatâ€™s hard for a
lot of people to understand, because itâ€™s legal.”
And aside from size and weight, the brains of children with fetal alcohol syndrome
(FAS) do not work as efficiently.
“The connections between different parts of the brain may also be impaired,”
says Streissguth. “So it isnâ€™t just structural differences in
the brain. There also appear to be real differences in the effectiveness with
which information is transmitted from one part of the brain to another.”
For a long time brain scientists have assumed this damage was irreversible,
and that there was little hope for recovery in children with FAS. But recent
research on brain
“plasticity” has changed the way we look at the ability of
our brains to change and repair themselves. And a new animal study on FAS
suggests there may be a chance for rehabilitation.
Forced intervention spurs the brain
Klintsova, psychology professor at SUNY Binghamton, exposed premature
rat pups to alcohol in order to mimic FAS, and let them mature into adults.
Compared to normal (control) rats, they had 30 percent fewer Purkinje
cells, neurons in the cerebellum which help control their movements, according
All rats were then forced to learn how to complete an obstacle course. The
alcohol-exposed rats had difficulty getting through the course, but over time
learned to complete it just as well as control rats. Whatâ€™s more, having
to learn the course increased the number of connections between Perkinje cells
in their brains.
This is the first time research has shown brain plasticity in alcohol exposed
(AE) rats. Previous studies placed AE rats in “enriched environments”,
in which, for instance, there were toys and obstacles as opposed to an empty
cage. While control rats experienced brain plasticity in these environments,
the AE rats did not. Klintsova says this is because “they were not interested
in exploring the enriched environments,” and likened them to kindergarten
children sitting in the corner rather than playing with toys and other children.
She and her colleagues believe it was the forced motor training that made
the difference for the AE rats. She thinks that something like physical therapy
for FAS might be a way to apply this work to humans.
Klintsova stresses that prevention of FAS (i.e., not drinking during pregnancy)
is still the most important message, but she feels that her work suggests
that kids born with brain damage might still be helped: “It gives us
the hope that with the appropriate targeted intervention, we can increase
The study—published in the journal Brain
Research and funded by the National
Institutes of Health—was a collaborative effort that also included
researchers at the University of Illinois at Urbana-Champaign, and Purdue