Constant exposure to the lights in neonatal intensive
care units could upset the development of premature
babies' biological clocks, a new study suggests.
The study found that exposing baby mice to constant
light prevented the master biological clock in
their brains from developing properly. That could
have long-term behavioral consequences, the U.S.
researchers say.
They noted that about 14 million low-weight babies
are born worldwide each year and are exposed to
artificial lighting in hospitals.
"We are interested in the effects of light
on biological clocks, because they regulate our
physiology extensively and also have an important
effect on our mood. This study suggests that cycling
the lights in NICUs may be better than constant
lighting for premature babies from the perspective
of developing their internal clocks," study
head Douglas McMahon, professor of biological
sciences at Vanderbilt University in Nashville,
Tenn., said in a prepared statement.
The study was expected to be published Monday
in the journal Pediatric Research.
The findings in this study of baby mice help
explain the results of several previous studies,
the researchers said. One of those studies found
that babies in neonatal units with day/night cyclic
lighting tended to begin sleeping through the
night more quickly than babies in units with constant
lighting.
Other studies found that babies in units with
day/night cyclic lighting gained weight faster
than babies in units with constant lighting.
