REM sleep

He famously contradicted Sigmund Freud’s views on the meaning of dreams.

Dreamers answered experimenters’ questions or solved simple math problems, showing that complex two-way communication between the dreaming and waking world is possible.

Researchers are experimenting with a variety of tools, from brain stimulation to audiovisual equipment, to try to take control of the sleeping brain.

Technologies such as noninvasive brain stimulation and virtual reality gaming offer insights into how dreams arise and what functions they might serve.

The activation of young brain cells in adult mice is necessary not just for forming memories, but consolidating them during rapid eye movement sleep, a study shows.

An unusual experiment suggests that interrupted REM sleep can interfere with the amygdala’s ability to process emotional memories overnight—in this case, the distressing memories of listening to oneself sing out of tune.

Pupil constriction during sleep may protect the murine brain from being awakened by sudden flashes of light.

Brain-derived neurotrophic factor affects onset and duration of REM in the animals, but not other phases of sleep.

Humans can remember new sensory information presented during REM sleep, but this ability is suppressed during deep, slow-wave slumber.

By examining brainwave patterns in a posterior cortical area, scientists can predict when people are dreaming.

Autonomic nervous system activity during sleep may help explain variation in the extent to which the behavior aids memory consolidation, a study shows.

An overview of the human sleep cycle

Mapping the dreaming brain through neuroimaging and studies of brain damage

Once believed to be unique to birds and mammals, sleep is found across the metazoan kingdom. Some animals, it seems, can’t live without it, though no one knows exactly why.

People who read from light-emitting electronic devices before bedtime may suffer poorer-quality sleep, researchers show.

Changing neural activity in the frontal and temporal lobes of the brain can cause a sleeper to become aware of her dreaming state, a study shows. 

Inducing certain brain patterns extends non-REM sleep in mice.