Transfer of congruency effects between Stroop and multiplication tasks: Evidence that retrieval of multiplication facts requires inhibitory control.

Inhibitory control is classically considered a domain-general process, yet recent findings suggest it may operate in context-specific ways. This has important implications for theories in other cognitive domains, such as mathematics, in which inhibitory control is proposed to play a key role. Inhibitory control has been implicated in resolving interference between competing number facts when retrieving them from memory, yet clear evidence for this is lacking. Here we report two pre-registered experiments with adults that investigated transfer of inhibitory control between interleaved Stroop and multiplication fact retrieval trials. Experiment 1 (n = 450) measured the congruency sequence effect, where transfer of inhibitory control between trials leads to a reduced congruency effect following an incongruent trial. Experiment 2 (n = 370) measured transfer of the list-wide proportion congruency effect, where the congruency effect is reduced when incongruent trials are more frequent. We found evidence of transfer of the congruency sequence effect between Stroop and multiplication. This did not differ depending on whether the Stroop task used number or animal stimuli. There was no transfer of the list-wide proportion congruency effect. These results suggest that reactive, transient domain-general inhibitory control processes are involved in retrieving multiplication facts from memory. Our findings have implications for theories of cognitive control and mathematical cognition, but caution should be taken in interpreting implications for educational interventions.