Yet another neurotic behaviour

Sarai (my furry debacle of a cat) is fairly neurotic. The one thing I can't figure out though is the following:

We have wall sconces in both the bedroom and living room of the apartment (this is instead of having ceiling lights). At various points in the evening, usually after a nap, Sarai will jump up on the desk right under one of the sconces in the living room and start hitting at it as if she sees a bug (even though we're pretty much bug-free). When the person who gets most annoyed at it stands up or says something to her, she will stop, but whine over and over until she decides to start hitting it again.

Sometimes playtime will stop it, or putting her in the darkened bedroom to nap, but often she will start over within a couple minutes. It's come to a point where it's not just irritating, but probably dangerous, as she could theoretically hit the bulb or socket, or maybe even break off a piece. Nothing seems to deter her from it, and nothing predicts when she'll start messing around again.

Any thoughts?

When I look at lights like that I sometime see "spots" before my eyes. I wonder if they could have the same effect on your cat and he thinks they are bugs. I know cat eyes are quite different but this is just a thought.

I tell you, I have a cat that insists on trying to break down my bedroom door. She will start at the end of the kitchen, run through the livingroom and throw herself at the door.

I'll trade with you.