An additive model for relations between AQT single- and dual-dimension naming speed.

Color-form naming in A Quick Test of Cognitive Speed (AQT) is used to assess processing speed on three rapid automatic naming tasks, two of which measure single-dimension and the third of which measures dual-dimension naming speed. These tests have been used to identify changes in processing speed associated with normal aging. The present study evaluated whether a simple additive model could explain the normally expected relation between scores on measures of single- and dual-dimension naming speed.