Incidental versus intentional encoding in the Deese–Roediger–McDermott paradigm: Does amnesic patients' implicit false memory depend on conscious activation of the lure?

Abstract

In two experiments, implicit false memory was investigated in Korsakoff patients and controls following incidental and intentional encoding in the Deese–Roediger–McDermott (DRM) paradigm. Participants were asked to think aloud, to investigate whether conscious lure activation occurs equally often in both groups under both types of instructions, and whether this influences the likelihood of later false memory. Results revealed normal priming for critical lures in amnesia following both types of encoding. Korsakoff patients did verbalize fewer lures than did controls during intentional encoding and showed impaired recognition performance. Lure verbalization was shown to contribute to explicit false memory, but had no clear effect on implicit memory. Together, results point to the conclusion that amnesic patients' encoding abilities are sufficient to obtain normal priming for critical lure words, and that conscious lure activation during study is not required to do so.

Keywords:

• False memory
• Korsakoff syndrome
• Gist memory
• Implicit memory
• Verbal reports

The authors would like to thank the psychiatric centers Sint-Amandus (Beernem) and Sint-Kamillus (Bierbeek) for coordinating the participation of their patients in the present experiments. Also many thanks to Jana Dekrem, Mieke Leyssen, and Stephanie Lauwers for their help with finding and testing control participants. Ilse Van Damme is a PhD Fellow of the Research Foundation–Flanders (FWO). The present work was also supported by Grant P6/29, to the second author, from the Interuniversity Attraction Poles program of the Belgian federal government. Parts of this work were presented at the XXIX International Congress of Psychology (ICP), Berlin, Germany (July 2008), at the 49th Annual Meeting of the Psychonomic Society, Chicago, USA (November 2008), and at the XVI Conference of the European Society for Cognitive Psychology (ESCOP), Krakow, Poland (September 2009).

Notes

¹When referring to “relational” encoding, we adopt the definition of Hunt and Einstein (1981; see also Hunt & McDaniel, 1993), referring to the encoding of information that is common to various input elements.