False memory ≠ false memory: DRM errors are unrelated to the misinformation effect.

James Ost,Georgina Jones,Kelly Salmon,Joanna Davies,Hartmut Blank,Katie Lambert,Lin Lu

doi:10.1371/journal.pone.0057939

Abstract

The DRM method has proved to be a popular and powerful, if controversial, way to study ‘false memories’. One reason for the controversy is that the extent to which the DRM effect generalises to other kinds of memory error has been neither satisfactorily established nor subject to much empirical attention. In the present paper we contribute data to this ongoing debate. One hundred and twenty participants took part in a standard misinformation effect experiment, in which they watched some CCTV footage, were exposed to misleading post-event information about events depicted in the footage, and then completed free recall and recognition tests. Participants also completed a DRM test as an ostensibly unrelated filler task. Despite obtaining robust misinformation and DRM effects, there were no correlations between a broad range of misinformation and DRM effect measures (mean r = −.01). This was not due to reliability issues with our measures or a lack of power. Thus DRM ‘false memories’ and misinformation effect ‘false memories’ do not appear to be equivalent.

Highlights

Driven by the controversy surrounding cases of adults who have reported recovering memories of childhood sexual abuse for which they claim to have been previously unaware, a large body of literature has focussed on variables that influence how such claims arise [1]
One important line of work has focused on individual differences and has shown that, for example, people who score higher on measures of dissociative experiences [2], [3], or who are fantasy prone [4] are more susceptible to certain kinds of memory errors
In the present paper we focus on misinformation endorsement because, if there is any association between the DRM errors and misinformation effects, this is where it should be found

Summary

Introduction

Driven by the controversy surrounding cases of adults who have reported recovering memories of childhood sexual abuse for which they claim to have been previously unaware, a large body of literature has focussed on variables that influence how such claims arise [1]. In the present study we took DRM free recall and recognition measures, and calculated signal detection indices of sensitivity and response bias The latter analyses were included to explore whether DRM errors and misinformation endorsement might be related at the source monitoring level [6], [15]. Put another way, are participants who are less able to discriminate new from old DRM items, or who adopt a liberal response bias towards new items, more likely to endorse misleading PEI as being part of the original witnessed event?

Methods

Results

Discussion