Biology

Exercise boosts the brain — and mental health
How you breathe affects your brain
When is the best time to exercise?
Good and bad memories are stored in different neurons, study finds
Injectable gel repairs severe spinal cord injuries and enables mice to walk
Brain implant translates neural activity into letters, letting a paralyzed man “speak”
Doctors may not be ready for blood tests that screen for multiple cancers at once
Chernobyl fungus could shield astronauts from cosmic radiation 
DNA-damaging molecules in the gut linked to colon cancer
Organ regeneration could overcome liver failure, without a transplant