Pro-saccade task: Subjects are asked to look at a green light in the centre of the screen and then look to the white spot on the right or left side. This is an automatic response.
Anti-saccade task: Subjects are asked to look at a red light in the centre of the screen and then, when the white spot appears, look in the opposite direction. This is NOT easy to do because you must first inhibit the automatic response and then make a movement to a location with no visual stimulus.