ITEM AND SOURCE MEMORY - DIFFERENTIAL AGE EFFECTS REVEALED BY EVENT-RELATED POTENTIALS

THE neural substrates of age-related memory differences were evaluated by recording event-related potentials (ERPs) from young and older adu lts during a recognition memory paradigm. Subjects studied two tempora lly distinct lists of sentences (each with two nouns) and were tested for their memory of the nouns and of the list (i.e. temporal source) i n which they had occurred. Compared with the young, the old showed a g reater source than item memory performance decrement. Both age groups showed equivalent posterior-maximal old/new ERP effects. However, only the young produced a frontal-maximal, late onset old/new effect that differed as a function of subsequent source attribution. Age-related e xplicit memory differences may be due to a deficit in a prefrontal cor tical system that underlies source memory.