Figure 14.

Average response-locked squeeze force of fast and slow correct responses, plotted separately for the correct channel (A) and the incorrect channel (B). C, Difference in squeeze force (correct minus incorrect). In A, neutral fast and slow and incongruent fast and slow curves are coincident. B shows activity in the incorrect channel that begins about 100 ms before the squeeze on the correct hand reaches criterion in slow trials in all three conditions (curves corresponding to congruent and neutral are coincident, for both fast and slow trials). In C, the difference in squeeze force activity on slow trials showed a “dip” toward the incorrect response ∼150 ms before response onset in all three conditions. On average, each participant contributed 730 trials to the congruent fast trials, 495 to congruent slow trials, 289 to incongruent fast trials, 580 to incongruent slow trials, 476 to neutral fast trials, and 580 to neutral slow trials.