PARTIAL ADVANCE INFORMATION AND RESPONSE PREPARATION - INFERENCES FROM THE LATERALIZED READINESS POTENTIAL

Response speed to a signal is faster when advance information about th e forthcoming movement is provided before signal onset. Although this precuing effect is well established, the location of this saving in re action lime (RT) in the information-processing system is controversial . Some authors have claimed that the precuing effect resides at a moto ric level, whereas others have suggested a nonmotoric locus. The prese nt experiments used onset latencies of the lateralized readiness poten tial (LRP) to locate the precuing effect. The results of 2 experiments with a highly compatible (Experiment 1) and with an incompatible (Exp eriment 2) stimulus-response mapping indicate that this effect resides , at least partially, in the motoric portion of RT. In addition, the L RP amplitude before signal appearance increased with the amount of adv ance information, supporting a muscle-specific preparation hypothesis.