The locus of dual-task interference: psychological refractory effects on movement-related brain potentials.

We sought to measure separately the motor potentials for each of 2 concurrent tasks and to use these measurements to identify the locus of dual-task interference. Lateralized readiness potentials (LRPs) were measured in the psychological refractory period paradigm, in which a separate response is required to each of 2 successive signals. As the interval between the signals decreased, the 2 reaction time (RT) tasks increasingly overlapped and the...