Plots on the left half of the figure depict the average signal response after collapsing all correct responses regardless of RT. These reflect the mean task-related activation during RW after a normal night's sleep or SD. Plots on the right half of the figure depict the relationship between delay in RT and fMRI signal. Delayed responses were associated with a modest but state-indifferent reduction in peristimulus signal and larger, state-sensitive increases in peak signal in frontoparietal control regions.