A tiger walks the same worn groove along the edge of its exhibit, like a broken record. A parrot methodically plucks out its own feathers until bare skin shows through. To a casual visitor, these can ...

Behaviors often include lying, impulsiveness and aggression. Many of those who've exhibited lifelong antisocial, aka sociopathic, behavior -- lying, impulsiveness, aggression, lacking concern for ...

The treatment of head lice might be worse than the actual lice. (Photo: Getty Images) A disturbing new study has linked a common chemical found in head lice treatments to behavioral difficulties in ...