Effect of Suppressing or Facilitating Tasks During Retention Interval in the Deese-Roediger-McDermott Paradigm: A Behavioral and Pupillometry Study

Objective: One of the most employed methods in analyzing false memories is the Deese, Roediger, and McDermott Paradigm (DRM), which permits false memories detection within a controlled experiment. An exciting aspect not fully addressed in DRM is the effect of a suppression or facilitation task during retention interval on the recognition test. This study aimed to investigate the effect of suppression or facilitation tasks during retention intervals and its effects on behavior performance and pupil dilation response to old and new words during the recognition task. Method: We randomly assigned 132 university students into two groups: one submitted to a free recall task (facilitation condition), and the other submitted to a letter fluency task (suppression condition) during the retention interval. Results: We found that the facilitation group recognized more old items than the suppression group; however, they showed no difference in false memory rates. Pupillary diameter pattern indicated that pupils dilate more for old words (targets) while contracting for new items (distractors), confirming the pupil old/new effect. Conclusions: The suppression group had a worse performance in hit responses than the facilitation group; nevertheless, suppression task affected neither false memory rates nor pupillary dilation patterns. The letter fluency task played a role in suppressing memory, by affecting performance for correct recognition of a stimulus; however, pupillary variation patterns comparisons between facilitation and suppression conditions show no sign of a greater significant cognitive effort for the latter during the recognition task. Public Significance Statement The present study suggests that performing suppression tasks during the retention interval of the DRM paradigm negatively affects memory accuracy in the recognition test. Additionally, although memory accuracy is affected, pupillary variation patterns comparisons between groups performing facilitation and suppression tasks show no sign of a greater significant cognitive effort for the latter during the recognition task.