Psychology, Department of


Date of this Version

January 1995


Published in Psychonomic Bulletin & Review 1995, 2 (2), 254-259. Copyright 1995 Psychonomic Society, Inc. Used by permission.


The purpose of the present research was to compare memory for an item with memory for the item’s source. Experiment 1 investigated discrimination between two external sources: each item in a list of words was spoken in either a male or a female voice. Subjects received a test of item recognition and a test of source monitoring at each of four delay intervals (immediate, 30 min, 48 h, 1 week). In contrast with previous research, no evidence of differential forgetting rates for item and source information was found. With delay intervals of 0 and 48 h, Experiment 2 replicated Experiment 1 while adding a reality monitoring condition that required discrimination between an internal (i.e., self-generated) and an external source. Subjects were better at making internal–external discriminations than at making external–external discriminations, but both types of source monitoring declined at the same rate as memory for the items themselves.