Switch costs reveal vocal-specific executive demands during flexible action selection in crows

Abstract

Crows and other corvids exhibit remarkable cognitive flexibility, exercising volitional control that allows them to select, initiate and withhold actions based on deliberate decisions rather than reflex. Among these behaviours, vocalizations are especially demanding, yet crows perform them with exceptional precision, paralleling core building blocks of human speech. Despite this, the executive mechanisms supporting intentional vocal control, and how they differ from those governing other voluntary actions, remain largely unknown. We trained carrion crows to produce either vocalizations or pecking responses to arbitrary visual cues presented in randomized, alternating or blocked sequences that controlled how often response modalities switched across trials. While crows performed both actions with high accuracy, vocalizations were consistently slower and more variable than pecking. Notably, vocalizations showed clear switch costs; transitions into vocal responses caused slower reaction times and occasional errors, whereas pecking was largely unaffected. These results show that crows can flexibly switch between motor modalities and that volitional vocalizations carry specific cognitive control demands, previously undescribed in birds. Crows thus stand out as a rare non-primate species in which volitional vocalizations integrate speed, accuracy and executive control.