A, the dorsolateral prefrontal cortex (DLPFC) (e.g. MNI coordinates: −28, 54, 20), B, the striatum (e.g. MNI coordinates: 10, 20, −10) and C, the anterior cingulate cortex (e.g. MNI coordinates: 8, 44, −4). D, E and F, show the average change in BOLD response produced by glucose, maltodextrin and their respective control solutions within the cluster of common activation highlighted in the dorsolateral prefrontal cortex, the striatum and the anterior cingulate cortex, respectively. *Significant difference between solutions (P < 0.05); **(P < 0.001). Values are mean ±s.e.m.