The sympathetic nervous system is your body's built-in alarm system. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. The sympathetic nervous ...

Shimmering, gelatinous comb jellies wouldn’t appear to have much to hide. But their mostly see-through bodies cloak a nervous system unlike that of any other known animal, researchers report in the ...

The sympathetic nervous system was thought to have evolved with jawed vertebrates. But lampreys—jawless, parasitic fish that suck out the blood of their hosts—have a simple one, per recent research.

When a person is at rest, meditating or reading a book, the parasympathetic nervous system is at work. Also known as the "rest and digest" system, the parasympathetic nervous system is responsible for ...