Sleep less, have a weak memory

London: Sleeping less may cause the brain to stop producing new cells that help in the formation of memories, according to a new study.

Researchers at Princeton University compared rats that were deprived of sleep for 72 hours with others that were not, reported the online edition of BBC News.

The study on rats found that lack of sleep affected the hippocampus - a brain region involved in forming memories.

The research, published in the journal Proceedings of the National Academy of Science, showed that a stress hormone caused the effect.

"People who experience lack of sleep are often faced with concentration problems, apart from other difficulties," said lead researcher Elizabeth Gould.

The study's findings could not be directly applied to humans because people did not go without sleep for 72 hours unless they were in extreme circumstances, said Neil Stanley, a sleep expert at the Norfolk and Norwich University Hospital.

"It is an interesting finding. It would be interesting to see if partial sleep deprivation - getting a little bit less sleep every night that you need - had the same effect,” Stanley added.