Deliens, G. , Schmitz, R. , Mary, A. & Peigneux, P.
UR2NF, Neuropsychology and Functional Neuroimaging Research Unit, Université Libre de Bruxelles, BRUXELLES, BELGIQUE
The aim of this study was to test post-learning consolidation and protection against interference processes in healthy volunteers (n = 9) in a within-subjects sleep deprivation (SD) paradigm. After learning a list of unrelated word pairs (A) subjects sleep or stay awake a whole night. Two days later, a novel list of word pairs (B) was learned just before delayed recall of the list A. List B was composed of 50% word pairs in which the initial word of the pair was also presented in list A, hence creating interference. Results indicate an interference effect in the sleep but not in the SD condition (p=0.004). Recall of word pairs subjected to interference in list B was lower than recall of word pairs not subjected to interference. Our findings may be in line with the reconsolidation theory in that after a night of sleep the reactivation of consolidated memory traces puts them back in a labile form, hence again sensitive to interference. By contrast, in the SD condition, subjects would create a dual trace (AB and AC) allowing them to fend off the negative impact of interference: the second list does not modify the first but the two lists coexist.