xbindkeys bind cursor move to right or left key press

I would like to program my mouse such that whenever the cursor is shifted right or left, the OS interprets this as a right key press or left key press. Which mouse events correspond to cursor right and left, and what would be the syntax to use in xbindkeys (as this seems like the right tool for it). Using xev -event mouse I see the cursor move gives MotionNotify events - can somehow cause the reception of this event to cause a right/left key press?