Is there a human bobblehead in your life?

While sitting with a group of family members, the only male in the group said, “You all look like a bunch of bobbleheads.” Apparently, we would all nod when someone else was talking. It has had me curious about this phenomenon ever since.

In a class on reading body language, the instructor said that this was relatively common in women. It means that they are listening, but not necessarily in agreement with what is being said.

Is it really true? Does this happen all over the world, or is it just a cultural habit in the US? Is it only seen being done by women? Do you do it?