A model for two-digit number processing based on a joint garner and system factorial technology analysis

As a vital part of our daily lives, number processing has received much attention in current cognitive research. Most adults perceive with ease the numerical magnitude of a two-digit number and also the individual magnitudes of the component digits, yet the relation between the 2 is poorly understood. Application to two-digit numbers of Garner's speeded classification paradigm (Experiment 1) and of system factorial technology (Experiment 2) jointly reveals phases of independent and of coactive processing within a well-defined time-course. A new model, the interactive race coactive model, explains various facets of two-digit number processing.