I've always wondered if this is a nervous condition. I have a relative who will

say something that she thinks is funny, (maybe it is or not) and right after she lets out an almost spasmodic Uh Hah! It's almost guttural. One time when my mother told a joke that was against Democrats and she knew I was a big Democrat (she was a Republican) she did the same laugh - I had never heard her laugh like that before.

I've looked up nervous laughter but that doesn't seem to match as it seems to be a response to a nervous situation.

Anyone familiar with this? I've known her all her life and she didn't do this when she was young.

EDIT: I am not so much worried about this person so much as I find it irritating. She's been doing this for most of her adult life.