The Scientist special topic: Sleep

Nice four articles:

The Gears of the Sleep Clock By Allan Pack:

When people have trouble sleeping--such as, in extreme cases, shift workers--those problems are not always rooted in disturbances in circadian rhythm, argues the University of Pennsylvania's ALLAN PACK. Instead, his studies of sleep have shown that the master clock is only one player in the molecular control of sleep.

Sleep adjusts fly synapses by Bob Grant:

New findings support a controversial hypothesis about the biological role of sleep: Snoozing may be a way for the brain to clear clutter accumulated after a hard day of synapse forming and strengthening. Two Science studies published today suggest that the brains of sleeping Drosophila undergo an overall depression in synaptic strength and number, eliminating some minor neuronal connections while merely weakening stronger ones.

Disappearing Before Dawn By Kelly Rae Chi:

Gene expression studies are lending support to a new, somewhat counterintuitive hypothesis for why every animal sleeps. KELLY RAE CHI visits the University of Wisconsin-Madison, where scientists are gathering evidence suggesting that we need sleep to prune back synapses, which tend to increase in strength throughout the day.

Why sleep?:

Sleep takes up around a third of our lives, and is an object of fascination during the other two thirds. "I dreamt that..." is surely among the top 10 conversation topics of all time. Given this, it is surprising how little attention is paid to the anthropology of sleep. Intriguing (but too little) work has been done on sleep practices in nonindustrialized societies, 1 and there has been some engaging speculation about sleep patterns; 2 it all points to our Western conventions as being a behavioral outlier.

How to catch a fly sleeping:

John Zimmerman at the Center for Sleep and Respiratory Neurobiology explains a new technique for determining when a fly is sleeping or awake - a prerequisite for fly-based sleep research: