Double Dissociation Between Item and Source Memory

The present experiment provides evidence for a double dissociation between item and source memory, thereby strengthening the claim that the 2 kinds of memory rely on different brain structures. Elderly participants were divided preexperimentally into 2 groups on the basis of their scores on a composite measure of frontal lobe function. In a subsequent test of sentence memory, the 2 groups did not differ; on a test of memory for the voice in which sentences were spoken, participants with high-frontal function outperformed those with low-frontal function. When the same participants were divided according to a composite measure of medial temporal lobe function, the high-functioning adults outperformed the low-functioning adults on memory for the sentence, but the groups did not differ on memory for voice. Results focus on different theories of frontal lobe function.