Table 1.

The four component processes isolated and manipulated in the current research

Component	Function	Example use
Visual search	Used when the subject scans the digit–symbol pairing key to find the current probe symbol	“Where is the plus symbol?”
Spatial memory	May gradually be incorporated across the task duration as the subject learns the approximate location of a symbol in the digit–symbol pairing key, allowing faster location of the probe symbol and associated digit	“The plus symbol is toward the left side of the digit–symbol pairing key.”
Paired- associate learning	May also be gradually developed across the task duration as the subject learns the digit–symbol pairing, allowing faster responding through reduced need to consult the digit–symbol pairing key	“The plus is paired with the number 3.”
Motor action	Used when the subject moves the index finger of the dominant hand to press the desired number key on the top of the keyboard	Using the index finger of the dominant hand to press the number 3.