Instruction (2 of 2)
Overall, you will have to do 20 consecutive arithmetic operations per trial. Beware that the correct result always has a value between 1 and 9.

A small "+" displayed in the center of the screen indicates that the next trial is about to start.

Try to be as accurate and as fast as possible.

Before the test starts, you will first do some practice trials to get used to the task.
Please press the right arrow key on your keyboard to proceed with the practice trials.