Wisconsin Card sorting test

I also tried the Wisconsing Card Sorting test myself. 

This is test with cards. The cards can have three different attributes: Color, Shape, Number. For each attribute, there are four different possibilities:

• Red, Green, yellow, Blue for Color
• Triangle, Star, Cross, Circle for Shape
• One, Two, Three, Four for Number.

The test starts with four cards with all three attributes with different values:

Then, one by one, new cards are presented. The objective is to add each new card to one of the four decks according to a "matching criterion". This criterion (Color, Shape or Number) is unknow in advance so you have to guess. The software tells you if you are correct or incorrect. It takes very few trials to learn that the matching criterion doesn't change randomly and that you doesn't need to gamble on each trial. For example, the matching criteria would be color, then they would maintain the same criteria for about 20 consequtive trials, until you get an "incorrect". If you pay attention, then you would try for any of the other two criteria until you get a "correct". Then you can adopt the new criterion for the next 20 or so trials.