Reconsolidation of episodic memories: A subtle reminder triggers integration of new information

Abstract

Recent demonstrations of “reconsolidation” suggest that memories can be modified when they are reactivated. Reconsolidation has been observed in human procedural memory and in implicit memory in infants. This study asks whether episodic memory undergoes reconsolidation. College students learned a list of objects on Day 1. On Day 2, they received a reminder or not, and then learned a second list. Memory for List 1 was tested immediately on Day 2 (Experiment 2) or on Day 3 (Experiment 1). Although the reminder did not moderate the number of items recalled from List 1 on either day, subjects who received a reminder incorrectly intermixed items from the second list when recalling List 1 on Day 3. Experiment 2 showed that this effect does not occur immediately and thus is time-dependent. The reminder did not affect memory for List 2 on Day 3 (Experiment 3), demonstrating that modification occurred only for the original memory (List 1). The study demonstrates the crucial role of reminders for the modification of episodic memory, that reconsolidation of episodic memory is time-dependent, and, in contrast to previous reconsolidation findings, that reconsolidation is also a constructive process, one that supports the incorporation of new information in memory.

Effects of psychosocial stress on episodic memory updating

“…Hupbach, Gomez, Hardt, and Nadel (2007) showed that updating effects are not observable immediately, though they are apparent after two days of learning List 2 in the reminder condition. Therefore, stress during the onset of reconsolidation may result in impaired updating.…”

“…Therefore, it is reasonable to hypothesize that memory updating might be impaired under stress, a possibility we decided to explore. We used a well-established episodic memory updating paradigm recently described for humans (Hupbach, Gomez, Hardt, & Nadel, 2007;Hupbach, Hardt, Gomez, & Nadel, 2008;Hupbach, Gomez, & Nadel, 2009). This updating paradigm involves learning a list of objects on Day 1.…”

Immediate and prolonged effects of cortisol, but not propranolol, on memory retrieval in healthy young men

“…While reconsolidation of fear related memories has most often been studied in animals, human declarative memories may also become labile during reactivation (Hupbach, Gomez, Hardt, & Nadel, 2007;Walker, Brakefield, Hobson, & Stickgold, 2003). Human studies on reconsolidation and the effects of cortisol and NA on this process are scarce.…”

Modification of episodic memories by novel learning: a failed replication study

“…With this break-down, we are able to investigate whether general memory change in the different groups is the result of participants incorporating new information (i.e. false alarms of pictures from Set 2) into the original memory (Hupbach et al, 2007, 2008) or whether new information only impairs the memory, but is not incorporated into the original memory (i.e. a lower percentage of hits) 1 .…”

“…Brunet et al, 2008; Kindt, Soeter, & Vervliet, 2009; Sevenster, Beckers, & Kindt, 2012, 2013; Soeter & Kindt, 2012), while the other line showed that memories can be altered with behavioural manipulations (e.g. Forcato et al, 2007; Hupbach, Gomez, Hardt, & Nadel, 2007; James et al, 2015; Schwabe & Wolf, 2009; Schiller et al, 2010; Wichert, Wolf, & Schwabe, 2011; 2013a, 2013b; see also van den Hout & Engelhard, 2012). Using behavioural manipulations, reactivated memories can be updated or disrupted during reconsolidation via novel learning (Ågren, 2014).…”