How Your Brain Cleans Itself—Mystery Solved? Thanks to a blood-brain barrier—a natural wall that protects the brain tissue—the organ never touches blood, thus protecting it from microbes, viruses, and other pathogens.
To get nutrients to brain tissue and remove its waste, the brain makes a liquid called cerebrospinal fluid. But exactly how the fluid removes gunk generated by brain cells wasn't certain until now. Experiments in the 1950s and '60s hinted that diffusion—the passive method by which, say, food coloring spreads out in a glass of water—moved cerebrospinal fluid around the brain. Yet this process is too slow to explain the brain's lightning-fast activity and immaculate cleanliness. It turns out that, while studying brain tissue, the researchers in the 1950s and '60s unwittingly turned off the plumbing that washes the tissue. How the Brain Stops Time.
One of the strangest side-effects of intense fear is time dilation, the apparent slowing-down of time. It's a common trope in movies and TV shows, like the memorable scene from The Matrix in which time slows down so dramatically that bullets fired at the hero seem to move at a walking pace. In real life, our perceptions aren't keyed up quite that dramatically, but survivors of life-and-death situations often report that things seem to take longer to happen, objects fall more slowly, and they're capable of complex thoughts in what would normally be the blink of an eye. Now a research team from Israel reports that not only does time slow down, but that it slows down more for some than for others. Psychopaths Get Time Off For Bad Brains.