Stressed Rats Cast Doubt on Sleep's Ability to Produce New Neurons

New results challenge the view that a good night's sleep can leave behind a dense bloom of brain cells in the morning. Prior studies had found that sleep-deprived rodents grow fewer new neurons than well-rested animals, suggesting that sleep somehow promotes the birth of brain cells, called neurogenesis. But that might not be the case: researchers report instead that lack of sleep likely cuts into neurogenesis by triggering a harmful stress response.