brain

Research scientists say they want to define Alzheimer's by the biological changes it causes in the brain, rather than by symptoms like memory loss.

High School athletes often raise money door-to-door for their teams. In Newton, Mass., a football player rang the doorbell of a leading brain injury researcher. Instead of money, he got a talk.

The brains of birds and mice continue to produce new nerve cells in the hippocampus throughout life. But research now suggests the human brain stops doing this around adolescence.

Thirst is what compels us to start hydrating. Now scientists have found a brain circuit in mice that seems to switch off thirst when they've taken in enough fluid and before it gets dangerous.

A Valentine's music video from Skunk Bear explores the ways your brain and body change when you fall in love — and change again as love deepens and matures.

Technology that uses electrical stimulation to tweak the brain may eventually help people with memory problems caused by a brain injury or Alzheimer's disease.

Scientists are keen to figure out how diet influences aging, including brain health. A 5-year study of healthy seniors found those who ate a serving or two of daily greens had less cognitive decline.

Researchers say it takes a lot of brainpower to stop an action, once it's underway. A study found that when people have to change a planned movement, 11 different brain areas have to get involved.

We are still as ignorant about the "passage from the physics of the brain to the corresponding facts of consciousness" as John Tyndall and his Victorian colleagues were, says Marcelo Gleiser.

A comparison of brain tissue from monkeys, chimps and humans suggests that our brains produce the chemical messenger dopamine, which plays a major role in pleasure and rewards, far differently.

Acts of altruism — like saving swimmers caught in a riptide from drowning or donating a kidney to a stranger — are among the thorniest puzzles of human nature, says guest blogger Abigail Marsh.

People can't simulate realistic, internal sensations, like temperature change or pain — which is a reason why more people aren't terrified by climate change, says guest blogger Lisa Feldman Barrett.