Sleep bolsters schematically incongruent memories

Abstract

Our ability to recall memories is improved when sleep follows learning, suggesting that sleep facilitates memory consolidation. A number of factors are thought to influence the impact of sleep on newly learned information, such as whether or not we rehearse that information (e.g. via restudy or retrieval practice), or the extent to which the information is consistent with our pre-existing schematic knowledge. In this pre-registered, online study, we examined the effects of both rehearsal and schematic congruency on overnight consolidation. Participants learned noun-colour pairings (e.g. elephant-red) and rated each pairing as plausible or implausible before completing a baseline memory assessment. Afterwards, participants engaged in a period of restudy or retrieval practice for the pairings, and then entered a 12 h retention interval of overnight sleep or daytime wakefulness. Follow-up assessments were completed immediately after sleep or wake, and again 24 h after learning. Our data indicated that overnight consolidation was amplified for restudied relative to retested noun-colour pairings, but only when sleep occurred soon after learning. Furthermore, whereas plausible (i.e. schematically congruent) pairings were generally better remembered than implausible (i.e. schematically incongruent) pairings, sleep (vs wake) reduced the retention advantage for plausible (vs implausible) information. This finding challenges the notion that schema-conformant memories are preferentially strengthened during post-learning sleep.

Sleep does not influence schema-facilitated motor memory consolidation

“…Previous literature in the declarative memory domain suggested a beneficial role of sleep in both declarative schema formation and schema-mediated integration 1,[11][12][13][14] , although a recent investigation reported no such beneficial effect of sleep for schema-congruent memories 18 . Current models of the beneficial effect of sleep on schema formation and integration posit that overlapping memory replay during sleep would lead to the formation of cognitive schemas stored in the neocortex.…”

“…Such a possibility would be consistent with previous research in the declarative memory domain. Sleep, and specific plasticity-related sleep features such as spindles and slow waves that are present in non-rapid-eye-movement (NREM) sleep, are thought to support declarative schema formation and subsequent integration of novel information [ 1,[11][12][13][14][15][16][17] although see 18 ]. While our previous results hinted that sleep may be crucial for the integration of novel motor information into a previously-acquired schema 7 , the design employed could not differentiate the specific effects of sleep from the influence of time.…”

Sleep does not influence schema-facilitated motor memory consolidation

“…Previous literature in the declarative memory domain suggested a beneficial role of sleep in both declarative schema formation and schema-mediated integration [ 1 , 11 – 14 ], although a recent investigation reported no such beneficial effect of sleep for schema-congruent memories [ 16 ]. Current models of the beneficial effect of sleep on schema formation and integration posit that overlapping memory replay during sleep would lead to the formation of cognitive schemas stored in the neocortex.…”

“…Such a possibility would be consistent with previous research in the declarative memory domain. Sleep, and specific plasticity-related sleep features such as spindles and slow waves that are present in non-rapid-eye-movement (NREM) sleep, are thought to support declarative schema formation and subsequent integration of novel information [[ 1 , 11 – 15 ] although see [ 16 ]]. While our previous results hinted that sleep may be crucial for the integration of novel motor information into a previously-acquired schema [ 7 ], the design employed could not differentiate the specific effects of sleep from the influence of time.…”