Event-related potentials (ERPs) were recorded during a recognition memory test for previously studied visual objects. Some studied objects were paired with the same context (landscape scenes) as at study, some were superimposed on a different studied context, and some were paired with new contexts. Unstudied objects were paired with either a studied or a new context. Three ERP memory effects were observed: an early effect elicited by all stimuli containing at least one studied component; a second effect elicited only by stimuli in which both object and context had been studied; and a third effect elicited by stimuli containing a studied object. Thus, test stimuli engaged three distinct kinds of memory-related neural activity which differed in their specificity for task-relevant features.