Influences of presentation mode and time pressure on the utilisation of advance information in response preparation.

An important approach to the investigation of movement selection and preparation is the precuing paradigm where preliminary information about a multidimensional response leads to reaction time benefits which are positively related to the amount of precue information. This so-called precuing effect is commonly attributed to data-limited preparatory motoric processes performed in advance of the response signal. By means of recording the lateralised readiness potential (LRP), the present experiments investigated whether the precuing effect could be explained also by variables that affect strategic utilisation of stimulus-conveyed information. Experiment 1 presented fully and partially informative precues either in mixed or blocked mode. Experiment 2 exerted various degrees of time pressure to the different precue conditions. In both experiments, the precuing effect on reaction times and the LRP was fully preserved, refuting the notion that the sensitivity of the LRP to the amount of preliminary information merely reflects differential precue utilisation. As a major finding, time pressure increased the LRP amplitude during response preparation which is consistent with the view that response strategies generally influence movement preparation on a motoric level.