Cognitive Process in Performing the Milwaukee Card Sorting Test

1. what executive processes are needed for good performance on the test,
2. how deficits in these processes are related to individual scores, and
3. how scores make up the three factors of the MCST

The figure should be read from the top (Error Occurs, Feedback Given). Moving to the left, the next three processes (boxes) reflect the cognitive abilities necessary for recognizing that an error has occurred and for changing the mental set. If any one of these processes does not occur, then a perseverative type of error (PR or APR) or a Verbal-Behavior Discord (VBD) error will take place, at which point the process returns to the top of the figure to begin again. When all three cognitive processes occur successfully twice in a row, then the person establishes a mental set (see EstSet diamond). If the person continues to repsond accurately for 10 trials in a row, then a Category is achieved (see Category diamond). The three factors found in the factor analysis are indicated in the figure by the bold, shaded boxes surrounding the corresponding score loadings.