Learning to be in control involves response-specific mechanisms

Conflict adaptation refers to our ability to modulate our attention in line with changing situational demands, so we can engage in goal-directed behavior. While there is ample evidence demonstrating that such adaptation in conflict tasks can be captured using different response modalities, it remains unknown whether these effects rely on domain-general mechanisms applied to different response modalities, or are the result of more inherently response-specific processes. Here, we used an individual-differences approach to evaluate whether conflict adaptation in two highly similar tasks using different response modalities are related. Specifically, participants performed two versions of a Stroop task, one in which they responded via key presses and one in which they responded via mouse movements. In both tasks, we manipulated the item-specific proportion of (in)congruent trials (80% vs. 20% congruent). This allowed us to evaluate the item-specific proportion congruency (ISPC) effect, a hallmark indicator of conflict adaptation. ISPC effects were observed in both response modalities. However, we found no indications that individual differences in the ISPC effects of the two response modalities were related. This raises the question whether findings from studies on conflict adaptation measured by different modalities can reliably be compared. Furthermore, these results suggest that response modality plays a more integrative role in these adaptive processes, rather than being the mere output of a domain-general control mechanism. This is consistent with contingency learning accounts of the ISPC effect and associative learning models of cognitive control.