Cursor out of Control

As I type while on the Internet, I lose control of the cursor completely. It slides slowly across the screen from bottom left to the middle top of the screen and then slides across the top of the screen to the right corner. I have no control until it finishes this cycle.

I have looked at “mouse” settings under “control panel”, but don’t see anything unusual. I’ve also scanned with Microfoft Anti-spy, Adaware and Norton Internet Security without any effect.