Lately, I've noticed that my teenage niece has been frequently posting to Facebook at 2 a.m. Her nighttime behavior wasn't particularly surprising, considering previous research that suggests adolescents are biologically programmed to go to bed later and wake up later. But I grew more concerned about her nocturnal Facebook habits after reading a new study showing that lack of sleep during adolescence could affect synapses needed for communication and inhibit normal development of the brain.
During the study (subscription required), researchers at the University of Wisconsin-Madison completed a series of experiments involving young mice to better understand how alterations to the sleep-wake cycle affected the anatomy of the developing adolescent brain. The experiments involved using a two-photon microscope to indirectly observe brain impulses in three groups of mice: those that were spontaneously awake for eight to 10 hours, others forced to stay awake and some allowed to sleep. Researchers determined being asleep or awake made a difference in the growth and depletion of the connections between nerve cells called synapses. Results showed overall density of dendritic spines, the elongated structures that contain synapses and thus allow brain cells to receive impulses from other brain cells, fell during sleep and rose during spontaneous or forced wakefulness.
Chiara Cirelli, MD, PhD, a co-author of the study commented on the significance of the findings in a university release:
Adolescence is a sensitive period of development during which the brain changes dramatically. There is a massive remodeling of nerve circuits, with many new synapses formed and then eliminated... 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.
Previously: Teens and sleep: A Q&A, Sleep deprivation may increase young adults’ risk of mental distress, obesity, Districts pushing back bells for the sake of teens’ sleep and Lack of sleep may be harmful to a teen’s well-being
Photo by Alyssa L. Miller