Find Out How Your Brain Sleeps

Obviously, your brain never stops working. So how does it rest?

When you lose consciousness and enter the deepest part of the sleep cycle, your brain stops communicating with itself, according to a new study from researchers at the University of Wisconsin-Madison. The awake brain functions as chemicals and nerve cells chatter continually, but in the deepest part of sleep, all those cranial pieces and parts break down into little islands that can't communicate with one another, report LiveScience and HealthDay News.

Led by professor of psychiatry Giulio Tononi, the team used a noninvasive technique called transcranial magnetic stimulation to activate certain parts of volunteer subjects' brains. Electrodes were attached to each person's head to monitor how the stimulation triggered reactions in other parts of the brain and body. When the volunteers were dreaming in the early morning hours, brain signals were almost as active as when they were awake, but during deeper sleep, the brain was quiet. "During deep sleep early in the night the response is short-lived and doesn't propagate at all," Tononi told LiveScience managing editor Robert Roy Britt.

Find Out What Will NOT Wake You Up [Netscape] What IS Consciousness? [Wikipedia] An Online Guide to Dream Interpretation [DreamMoods] Why Some of Us Are Larks and Others Are Night Owls [Netscape] Dream Dictionary: The Meaning of Dreams [Dream Dictionary]

Research team member Marcello Massimini, a research associate at the Wisconsin university's Psychiatric Institute and Clinics, explains that the brain is compartmentalizing to allow the synapses--those areas in the brain that let us think--to take a break and rest. "This process would allow cortical circuits to eliminate noisy synapses and renormalize in order to be ready for the next day," Massimini told LiveScience. He added that this process may also explain the well-known phenomenon of improved performance and learning after sleep.

The study findings, which were published in the journal Science, help clarify scientific thought about consciousness. Tononi told HealthDay News that conscious thought depends on the ability of the brain to integrate information, and this research helps verify that belief.

http://cnn.netscape.cnn.com/news/package.jsp?name=fte/brainsleeps/brainsleeps&floc=wn-np