The ingestion of a glucose containing drink has been shown to improveperformance on a variety of cognitive tasks. There is debate, however, asto whether glucose especially benefits hippocampal memory functioningor whether it has a more global effect on attentional systems. The presentstudy used event related potential methodology (ERPs) to investigatefurther glucose-mediated cognitive processes. Each participant acted ashis/her own control in a repeated measures design, receiving one of twopossible treatments (25g glucose vs. placebo) in a counterbalancedorder. After a two hour fasting period participants completed a visualthree-stimulus oddball task. This paradigm involves an individualdetecting an infrequent target stimulus randomly embedded in a train ofrepetitive background or standard stimuli. Detection of the targetresults in a large P3b ERP component (memory updating effect).The infrequent presentation of a novel and irrelevant stimulus, randomlyinterspersed with the target and standard stimuli, generates a P3aresponse (orientation of attention effect). These components were usedas markers to establish whether the glucose enhancement effect wasrestricted to the neuro-cognitive processes related to memory. Consistentwith behavioural work, glucose moderated the magnitude and latency ofthe P3b ERP component. However, glucose also interacted withattentional systems (P3a and an earlier P2), although this effect wasnon-significant. This work converges with recent fMRI findings indicatingthe sensitivity of the medial-temporal lobes and the pre-frontal cortex toglucose administration.