834 - 827 - 820 - 813 - 806 - 799 - - - - -

There are several automated version of this test. We use one with a Yes-No choice. 

First you see a number, and memorise it

834

Then the next number appears. 827 is 7 less than 834, so you tap YES

827

Then the next number. 818 is not 7 less than 827, so you tap NO

818

Then the next number. 811 is 7 less than 818, so you tap YES

811

We record the reaction times averaged over the test, and the total number of errors.

This test can be run on a tablet computer or a Java-enabled mobile phone.