What is the origin of the idiom "one's eyes on stalks" and when to use it?

The idiom "one's eyes on stalks" is a colorful expression that conveys extreme surprise, confusion, or amazement. It is believed to have originated from the idea that when someone is utterly shocked or fascinated by something, their eyes appear as if they are extended on long stalks, like those of a snail or certain insects. This idiom is primarily used in informal and spoken language.