Education 2.0 & 3.0

The National Sleep Foundation recommends an average of eight hours of sleep per night for adults, but sleep scientist Matthew Walker says that too many people are falling short of the mark.

“Human beings are the only species that deliberately deprive themselves of sleep for no apparent gain,” Walker says. “Many people walk through their lives in an underslept state, not realizing it.”

Walker is the director of the Center for Human Sleep Science at the University of California, Berkeley. He points out that lack of sleep — defined as six hours or fewer — can have serious consequences. Sleep deficiency is associated with problems in concentration, memory and the immune system, and may even shorten life span.

“Every disease that is killing us in developed nations has causal and significant links to a lack of sleep,” he says. “So that classic maxim that you may [have] heard that you can sleep when you’re dead, it’s actually mortally unwise advice from a very serious standpoint.”

Via John Evans, Miloš Bajčetić

The reason we sleep goes far beyond simply replenishing our energy levels every 12 hours - our brains actually change states when we sleep to clear away the toxic byproducts of neural activity left behind during the day.

Weirdly enough, the same process starts to occur in brains that are chronically sleep-deprived too - except it's kicked into hyperdrive. Researchers have found that persistently poor sleep causes the brain to clear a significant amount of neurons and synaptic connections, and recovering sleep might not be able to reverse the damage.

A team led by neuroscientist Michele Bellesi from the Marche Polytechnic University in Italy has examined the mammalian brain's response to poor sleeping habits, and found a bizarre similarity between the well-rested and sleepless mice.

Like the cells elsewhere in your body, the neurons in your brain are being constantly refreshed by two different types of glial cell - support cells that are often called the glue of the nervous system.

The microglial cells are responsible for clearing out old and worn out cells via a process called phagocytosis - meaning "to devour" in Greek.

The astrocytes' job is to prune unnecessary synapses (connections) in the brain to refresh and reshape its wiring.

We've known that this process occurs when we sleep to clear away the neurological wear and tear of the day, but now it appears that the same thing happens when we start to lose sleep.

Via Wildcat2030, Miloš Bajčetić