Limited-capacity identity processing of multiple integers

The architecture of the numerical cognition system is currently not well understood, but at a general level, assumptions are made about two core components: a quantity processor and an identity processor. The quantity processor is concerned with accessing and using the stored magnitude denoted by a given digit. The identity processor is concerned with the recovery of the corresponding digit’s identity. Blanc-Goldhammer and Cohen (2014) established that the recovery and use of quantity information operates in an unlimited capacity fashion. Here, we assess whether the identity processor operates in a similar fashion. We present two experiments that are digit identity variations of Blanc-Goldhammer and Cohen’s (2014) magnitude estimation paradigm. The data across both experiments reveal a limited capacity identity processor whose operation reflects cross-talk with the quantity processor. Such findings provide useful evidence that is used to adjudicate between competing models of the human number processing system.