What's easier: doing what you want, or being told what to do? Cued versus voluntary language and task switching.

The current study contrasted cued versus voluntary switching to investigate switching efficiency and possible sharing of control mechanisms across linguistic and nonlinguistic domains. Bilinguals switched between naming pictures in Spanish versus English or between reading numbers aloud versus adding their digits, either without or with repetition of stimuli and with fewer requirements as to when and how much they had to switch relative to previous instantiations of voluntary switching. Without repetition (Experiment 1), voluntary responses were faster than cued responses on both stay and switch trials (especially in the nonlinguistic switching task), whereas in previous studies the voluntary advantage was restricted to switch-cost reduction. Similarly, when targets were presented repeatedly (Experiment 2), voluntary responses were faster overall for both linguistic and nonlinguistic switching, although here the advantage tended to be larger on switch trials and cross-domain similarity appeared to reflect nonoverlapping switching strategies. Experiment 3 confirmed the overall voluntary speed advantage for the read-add task in monolinguals and revealed a reduction in switch costs only for a different nonlinguistic task (size-parity judgments). These results reveal greater overall advantages for voluntary over cued switching than previously reported but also that the precise manifestation of the voluntary advantage can vary with different tasks. In the linguistic domain, lexical inaccessibility introduces some unique control mechanisms, and repetition may magnify cross-domain overlap in control mechanisms. Finally, under some limited conditions, cost-free switches were found in both linguistic and nonlinguistic domains; however, suspension of top-down control may be restricted to language or highly automatic tasks.