Two independent, but complementary, studies on premature births, indicated that pre-term babies are not necessarily disadvantaged mentally, says New Scientist (26 January, 2013).
Stephen Back at the
Oregon Health & Science University in Portland, America, studied brains of
sheep fetuses because they are similar to the brains of human fetuses. His team
studied the cerebral cortex to determine the number of neurons. A small
cerebral cortex in premature babies was assumed to reflect a lack of neurons,
because some of the cells die when there is a reduced blood flow to the brain
tissue (called ischemia) that often happens to premature babies.
Back’s team compared
neuron numbers in sheep brains that had experienced ischemic injury with
non-injured sheep brains. The numbers were the same, indicating that the
neurons were intact and not damaged. However, the team noted that the cells
were “all squished together” and differed in shape in the injured brains of the
premature sheep. They lacked the branches (called dendrites) that radiate from
healthy neurons. “Instead of oak trees [in shape], we saw saplings,” Back said.
In a similar study,
Steven Miller at the Hospital for Sick Children in Toronto, Canada, studied the
links between neonatal care and brain development in 95 pre-term babies. Miller’s
team noted that the whole brain was not influenced, only the cerebral cortex.
The team took MRI scans on babies 32-40 weeks old, which showed the same
situation as Back’s team: the neurons were damaged, but not dead.
The two research teams
think they are witnessing the same results. They show that premature babies do
not have dead brain cells, just damaged ones – which means that they have a “disorder
of maturation, not loss.”
Miller’s study indicated
that the damaged cells might be nurtured back to health with the right
nutrition or cognitive stimulation that could stimulate brain growth. Zoltan
Molnar of the University of Oxford in England thinks the work is
groundbreaking, but the studies could have assessed other brain regions too, or
a more complete picture, reports New Scientist. David Edwards at the University
College London says it might be premature to get too excited – although the
damaged cells appear to be repairable, he wonders by how much.
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