Sleep Preserves Original and Distorted Memory Traces

TY - JOUR

T1 - Sleep Preserves Original and Distorted Memory Traces

AU - Cairney, Scott Ashley

AU - Lindsay, Shane

AU - Paller, Ken A.

AU - Gaskell, Mark Gareth

N1 - © 2017 The Authors. Published by Elsevier Ltd.

PY - 2018/2

Y1 - 2018/2

N2 - Retrieval facilitates the long-term retention of memories, but may also enable stored representations to be updated with new information that is available at the time of retrieval. However, if information integrated during retrieval is erroneous, future recall can be impaired: a phenomenon known as retrieval-induced distortion (RID). Whether RID causes an “overwriting” of existing memory traces or leads to the co-existence of original and distorted memory traces is unknown. Because sleep enhances memory consolidation, the effects of sleep after RID can provide novel insights into the structure of updated memories. As such, we investigated the effects of sleep on memory consolidation following RID. Participants encoded word locations and were then tested before (T1) and after (T2) an interval of sleep or wakefulness. At T2, the majority of words were placed closer to the locations retrieved at T1 than to the studied locations, consistent with RID. After sleep compared with after wake, the T2-retrieved locations were closer to both the studied locations and the T1-retrieved locations. These findings suggest that RID leads to the formation of an additional memory trace that corresponds to a distorted variant of the same encoding event, which is strengthened alongside the original trace during sleep. More broadly, these data provide evidence for the importance of sleep in the preservation and adaptive updating of memories.

AB - Retrieval facilitates the long-term retention of memories, but may also enable stored representations to be updated with new information that is available at the time of retrieval. However, if information integrated during retrieval is erroneous, future recall can be impaired: a phenomenon known as retrieval-induced distortion (RID). Whether RID causes an “overwriting” of existing memory traces or leads to the co-existence of original and distorted memory traces is unknown. Because sleep enhances memory consolidation, the effects of sleep after RID can provide novel insights into the structure of updated memories. As such, we investigated the effects of sleep on memory consolidation following RID. Participants encoded word locations and were then tested before (T1) and after (T2) an interval of sleep or wakefulness. At T2, the majority of words were placed closer to the locations retrieved at T1 than to the studied locations, consistent with RID. After sleep compared with after wake, the T2-retrieved locations were closer to both the studied locations and the T1-retrieved locations. These findings suggest that RID leads to the formation of an additional memory trace that corresponds to a distorted variant of the same encoding event, which is strengthened alongside the original trace during sleep. More broadly, these data provide evidence for the importance of sleep in the preservation and adaptive updating of memories.

KW - Consolidation

KW - Distortion

KW - Memory

KW - Retrieval

KW - Sleep

UR - http://www.scopus.com/inward/record.url?scp=85033583333&partnerID=8YFLogxK

U2 - 10.1016/j.cortex.2017.10.005

DO - 10.1016/j.cortex.2017.10.005

M3 - Article

SN - 0010-9452

VL - 99

SP - 39

EP - 44

JO - Cortex

JF - Cortex

ER -