Research indicates that glucocorticoids affect hippocampal function and the form of cognition that the hippocampus is thought to subserve, explicit memory. However, some studies suggest that glucocorticoids affect the frontal lobe, attention and working memory. Thus, it is not clear whether glucocorticoids specifically target the hippocampus and explicit memory or if the effects are more ubiquitous. By simultaneously measuring event-related potentials and behavioral performance in tasks designed to tap particular cognitive and neural processes, the present study examined the effects of hydrocortisone on 24 healthy humans. In an intentional face recognition memory task where the stimuli were presented again after a brief delay (6-18 s) and a long delay (30 min), hydrocortisone altered the P600 component (an electrophysiological index of recognition memory and hippocampal activity) following the brief delay and impaired behavioral performance after the long delay. ERPs and behavioral performance were not affected in the attention and working memory tasks. These findings are consistent with reports indicating that glucocorticoids affect explicit memory and hippocampal function.