Neural mechanisms supporting the extraction of general knowledge across episodic memories.
General knowledge acquisition entails the extraction of statistical regularities from the environment. At high levels of complexity, this may involve the extraction, and consolidation, of associative regularities across event memories. The underlying neural mechanisms would likely involve a hippocampo-neocortical dialog, as proposed previously for system-level consolidation. To test these hypotheses, we assessed possible differences in consolidation between associative memories containing cross-episodic regularities and unique associative memories. Subjects learned face-location associations, half of which responded to complex regularities regarding the combination of facial features and locations, whereas the other half did not. Importantly, regularities could only be extracted over hippocampus-encoded, associative aspects of the items. Memory was assessed both immediately after encoding and 48 h later, under fMRI acquisition. Our results suggest that processes related to system-level reorganization occur preferentially for regular associations across episodes. Moreover, the build-up of general knowledge regarding regular associations appears to involve the coordinated activity of the hippocampus and mediofrontal regions. The putative cross-talk between these two regions might support a mechanism for regularity extraction. These findings suggest that the consolidation of cross-episodic regularities may be a key mechanism underlying general knowledge acquisition.
Department of Psychology, University of Amsterdam, Netherlands; Cognitive Science Center Amsterdam, University of Amsterdam, Netherlands. Electronic address: sweegers@gmail.com.
Carly C G
CC
Sweegers
Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Netherlands; Behavioural Science Institute, Radboud University Nijmegen, Netherlands.
Atsuko
A
Takashima
Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Netherlands; Department of Cognitive Neuroscience, Radboud University Medical Centre, Netherlands.
Guillén
G
Fernández
Department of Psychology, University of Amsterdam, Netherlands; Cognitive Science Center Amsterdam, University of Amsterdam, Netherlands.
Lucia M
LM
Talamini
D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D061212:Memory, Episodic; D009434:Neural Pathways / Q000502:physiology*; D055815:Young Adult
Episodic memory; Hippocampus; Semantic memory; System-level consolidation; fMRI