Differential cortical responses associated with the fastest 10% RTs and the slowest 10% RTs after RW and SD. There was higher peak fMRI signal for the slowest 10% of trials in the medial frontal cortex (top) and bilateral intraparietal sulcus (middle). Between-state differences were observed only for the slowest 10% RTs in bilateral intraparietal sulcus and the inferior occipital cortices (bottom). Peak signal was significantly lower in the occipital region even for the fastest responses across states. Random effects analysis using a threshold of p < 0.001 was to detect task-related activation. Significant differences between peak signal associated with a lapse and the average response for each state are marked with an asterisk. The shaded time points indicate those contrasted to assess significant state effects. The inset shows the mean peak signal associated with the time points under consideration. Error bars represent SEM. *p < 0.01, **p < 0.001.