Figure 5. Within-subject fMRI results.

(a) When examining the response to infrequent stimuli collapsed across the four tasks, robust transient activation was evident within a set of brain regions that included inferior frontal cortex. However, this activation was no greater in the INHIBITION variant of the task (t contrast whole-brain FDR-corrected at P<0.05). (b) Activation within the AIFO bilaterally, the ACC and preSMA was greater for failed relative to successful inhibition trials (t contrast rendered at P<0.01 uncorrected for display purposes). (c) The AIFO bilaterally, the ACC and preSMA were the only frontal-lobe regions to show significantly greater sustained activation when contrasting task blocks versus rest blocks (t contrast whole-brain FDR-corrected at P<0.05). (d,e) A set of brain regions including the right AIFO and the right IFS were strongly activated in the early blocks, when learning was maximal relative to the late blocks, when responses were established (t contrast whole-brain FDR-corrected at P<0.05). No frontal lobe areas showed heightened activation during late blocks relative to early blocks when applying a liberal uncorrected threshold of P<0.01.