The task would be as follows: two numbers (e.g. -10 and 10) mark the extremities of a line, which is constant from trial to trial; a series of numbers appear one by one in the upper part of the screen, and the participant has to click on the line where they think that number should be (so, for instance, the number 1 would require a click a little to the right of the line's midpoint, if the line goes from -10 to 10).