PMID- 36251731
OWN - NLM
STAT- MEDLINE
DCOM- 20221031
LR  - 20221031
IS  - 1553-7358 (Electronic)
IS  - 1553-734X (Print)
IS  - 1553-734X (Linking)
VI  - 18
IP  - 10
DP  - 2022 Oct
TI  - Hippocampal and medial prefrontal cortices encode structural task representations 
      following progressive and interleaved training schedules.
PG  - e1010566
LID - 10.1371/journal.pcbi.1010566 [doi]
LID - e1010566
AB  - Memory generalisations may be underpinned by either encoding- or retrieval-based 
      generalisation mechanisms and different training schedules may bias some learners 
      to favour one of these mechanisms over the other. We used a transitive inference 
      task to investigate whether generalisation is influenced by progressive vs 
      randomly interleaved training, and overnight consolidation. On consecutive days, 
      participants learnt pairwise discriminations from two transitive hierarchies 
      before being tested during fMRI. Inference performance was consistently better 
      following progressive training, and for pairs further apart in the transitive 
      hierarchy. BOLD pattern similarity correlated with hierarchical distances in the 
      left hippocampus (HIP) and medial prefrontal cortex (MPFC) following both 
      training schedules. These results are consistent with the use of structural 
      representations that directly encode hierarchical relationships between task 
      features. However, such effects were only observed in the MPFC for recently 
      learnt relationships. Furthermore, the MPFC appeared to maintain structural 
      representations in participants who performed at chance on the inference task. We 
      conclude that humans preferentially employ encoding-based mechanisms to store 
      map-like relational codes that can be used for memory generalisation. These codes 
      are expressed in the HIP and MPFC following both progressive and interleaved 
      training but are not sufficient for accurate inference.
FAU - Berens, Sam C
AU  - Berens SC
AUID- ORCID: 0000-0001-8197-8745
AD  - School of Psychology, University of Sussex, Brighton, United Kingdom.
FAU - Bird, Chris M
AU  - Bird CM
AD  - School of Psychology, University of Sussex, Brighton, United Kingdom.
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20221017
PL  - United States
TA  - PLoS Comput Biol
JT  - PLoS computational biology
JID - 101238922
SB  - IM
MH  - Humans
MH  - *Hippocampus
MH  - *Magnetic Resonance Imaging/methods
MH  - Temporal Lobe
MH  - Learning
MH  - Prefrontal Cortex/diagnostic imaging
PMC - PMC9612823
COIS- The authors have declared that no competing interests exist.
EDAT- 2022/10/18 06:00
MHDA- 2022/11/01 06:00
PMCR- 2022/10/17
CRDT- 2022/10/17 13:45
PHST- 2022/03/08 00:00 [received]
PHST- 2022/09/13 00:00 [accepted]
PHST- 2022/10/27 00:00 [revised]
PHST- 2022/10/18 06:00 [pubmed]
PHST- 2022/11/01 06:00 [medline]
PHST- 2022/10/17 13:45 [entrez]
PHST- 2022/10/17 00:00 [pmc-release]
AID - PCOMPBIOL-D-22-00347 [pii]
AID - 10.1371/journal.pcbi.1010566 [doi]
PST - epublish
SO  - PLoS Comput Biol. 2022 Oct 17;18(10):e1010566. doi: 10.1371/journal.pcbi.1010566. 
      eCollection 2022 Oct.