London: Parents, please note - make sure that your teenage children get adequate sleep daily, for a new study has claimed sleep deficiency could affect their brains later in life.

Researchers at the University of Wisconsin-Madison have carried out the study and found that sleep-deprived teenagers are at risk of long-term damage to wiring of their brains reports said.

They found that short-term sleep restriction prevents the balanced growth and depletion of brain synapses, which are the connections between nerve cells where communication occurs.

"One possible implication of our study is that if you lose too much sleep during adolescence, especially chronically, there may be lasting consequences in terms of the wiring of the brain," said lead researcher Dr Chiara Cirelli.

Mental illnesses such as schizophrenia tend to start during adolescence but the exact reasons remain unclear, say the researchers.

"Adolescence is a sensitive period of development during which the brain changes dramatically. There is a massive remodelling of nerve circuits, with many new synapses formed and then eliminated," she said.

For their study, the researchers analysed the brains of mice. They wanted to see how alterations to the sleep-wake cycle affected the anatomy of the developing adolescent brain in the animals.

Using a two-photon microscope, the researchers indirectly followed the growth and retraction of synapses by counting dendritic spines, the elongated structures that contain synapses and thus allow brain cells to receive impulses from other brain cells.

They compared adolescent mice that for eight to 10 hours were spontaneously awake, allowed to sleep or forced to stay awake. The live images showed that being asleep or awake made a difference in the dynamic adolescent mouse brain – the overall density of dendritic spines fell during sleep and rose during spontaneous or forced wakefulness.
"These results using acute manipulations of just eight to 10 hours show that the time spent asleep or awake affects how many synapses are being formed or removed in the adolescent brain," Prof Cirelli said.

She added, "The important next question is what happens with chronic sleep restriction, a condition that many adolescents are often experiencing. It could be that the changes are benign, temporary and reversible or there could be lasting consequences for brain maturation and functioning."

The findings have been published in the latest edition of the 'Nature Neuroscience' journal.