...the Wisconsin card-sorting task, which requires the patient to sort a special deck of cards into two piles.
“I had that one. All cards with red symbols were supposed to be placed in the right-hand pile, all other colors in the left-hand pile.”
But of course the patient has to figure this out from the responses elicited from the neuropsychologist. The patient is not given any specific instruction. He just starts sorting the cards into two piles and the neuropsychologist says yes or no after each card, depending on whether the correct criterion for sorting was used — in the example, yes if a card with a red symbol was placed on the right pile. Patients catch on to the criterion after a short while and soon are hearing a yes after each card. But that’s not the hard part.
Partway through the deck, the neuropsychologist changes the criterion without any warning. Now it’s yes if cards with three symbols are placed on the right pile, regardless of color. Since the neuropsychologist doesn’t mention that the criterion has changed, the patient’s only clue is hearing no. Over and over. A normal person soon realizes that the rules have changed and tries another sorting pattern and eventually discovers the new criterion by a string of yes responses.
“So that’s what was going on. It was rather fun, actually. But maybe that’s because I caught on each time she changed signals on me.”
The patient with damage to one frontal lobe catches on to the original sorting strategy and gets the string of yes answers. But, when the needed strategy changes, he keeps on sorting the cards the way he started out, red on right, despite the string of no answers that this elicits. He seems unable to adapt his behavior to the new game. So it’s the same problem as in Luria’s patients, an inability to adapt behavior to contingencies.