Fersiynau electronig

Dogfennau

Dangosydd eitem ddigidol (DOI)

  • Nicholas E. Souter
    University of York
  • Antonia de Freitas
    University of York
  • Meichao Zhang
    University of York
  • Ximing Shao
    University of York
  • Tirso Rene del Jesus Gonzalez Alam
    University of York
  • Haakon Engen
    University of Oslo
  • Jonathan Smallwood
    Queen’s University, Kingston, Canada
  • Katya Krieger-Redwood
    University of York
  • Elizabeth Jefferies
    University of York
The default mode network (DMN) lies towards the heteromodal end of the principal gradient of intrinsic connectivity, maximally separated from the sensory-motor cortex. It supports memory-based cognition, including the capacity to retrieve conceptual and evaluative information from sensory inputs, and to generate meaningful states internally; however, the functional organisation of DMN that can support these distinct modes of retrieval remains unclear. We used fMRI to examine whether activation within subsystems of DMN differed as a function of retrieval demands, or the type of association to be retrieved, or both. In a picture association task, participants retrieved semantic associations that were either contextual or emotional in nature. Participants were asked to avoid generating episodic associations. In the generate phase, these associations were retrieved from a novel picture, while in the switch phase, participants retrieved a new association for the same image. Semantic context and emotion trials were associated with dissociable DMN subnetworks, indicating that a key dimension of DMN organisation relates to the type of association being accessed. The frontotemporal and medial temporal DMN showed a preference for emotional and semantic contextual associations, respectively. Relative to the generate phase, the switch phase recruited clusters closer to the heteromodal apex of the principal gradient-a cortical hierarchy separating unimodal and heteromodal regions. There were no differences in this effect between association types. Instead, memory switching was associated with a distinct subnetwork associated with controlled internal cognition. These findings delineate distinct patterns of DMN recruitment for different kinds of associations yet common responses across tasks that reflect retrieval demands. [Abstract copyright: © 2024 The Authors. Human Brain Mapping published by Wiley Periodicals LLC.]

Allweddeiriau

Iaith wreiddiolSaesneg
Rhif yr erthygle26703
Tudalennau (o-i)e26703
CyfnodolynHuman Brain Mapping
Cyfrol45
Rhif y cyfnodolyn7
Dynodwyr Gwrthrych Digidol (DOIs)
StatwsCyhoeddwyd - 8 Mai 2024
Gweld graff cysylltiadau