http://scienceyear.net/2015/10/16/dreams-turned-off-and-on-with-a-neural-switch/At the flip of a switch, University of California, Berkeley, neuroscientists can send a sleeping mouse into dreamland. The researchers inserted an optogenetic switch into a group of nerve cells located in the ancient part of the brain called the medulla, allowing them to activate or inactivate the neurons with laser light. When the neurons were activated, sleeping mice entered REM sleep within seconds. REM sleep, characterized by rapid eye movements, is the dream state in mammals accompanied by activation of the cortex and total paralysis of the skeletal muscles, presumably so that we don’t act out the dreams flashing through our mind.
