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 behavioural consequences, the US researchers say.
They noted that about 14 million low-weight babies are born worldwide each year and are exposed to artificial lighting in hospitals.
Important effect on mood
"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, Tennessee, said in a prepared statement.
The study was expected to be published Monday in the journal Pediatric Research.
Previous studies explained
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. - (HealthDayNews, August 2006)
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