Symbol Digit Substitution Test

Digit Symbol Substitution Task

Background Information

The Digit Symbol Substitution Task is a well established psychometric test paradigm which is used to measure general cognitive performance. Subjects must match symbols to digits and press the key which corresponds to the digit. The test is designed as a continous performance task in whcih the subject must accomplish as many as possible correct matches within a three minute test period.

Since the task instruction is rather simple, yet demanding, the task is very popular to measure continuous performance with high mental workload. Since subjects learn over time the assignment while they perform the task , this test also includes a memory component. Due to this mix of involved cognitive functions, effects are rather unspecific, but reliable.


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