Dynamic causal modeling of load-dependent modulation of effective connectivity within the verbal working memory network

Danai Dima, Jigar Jogia, Sophia Frangou

Research output: Contribution to journalArticle

Abstract

Neuroimaging studies have consistently shown that working memory (WM) tasks engage a distributed neural network that primarily includes the dorsolateral prefrontal cortex, the parietal cortex, and the anterior cingulate cortex. The current challenge is to provide a mechanistic account of the changes observed in regional activity. To achieve this, we characterized neuroplastic responses in effective connectivity between these regions at increasing WM loads using dynamic causal modeling of functional magnetic resonance imaging data obtained from healthy individuals during a verbal n-back task. Our data demonstrate that increasing memory load was associated with (a) right-hemisphere dominance, (b) increasing forward (i.e., posterior to anterior) effective connectivity within the WM network, and (c) reduction in individual variability in WM network architecture resulting in the right-hemisphere forward model reaching an exceedance probability of 99% in the most demanding condition. Our results provide direct empirical support that task difficulty, in our case WM load, is a significant moderator of short-term plasticity, complementing existing theories of task-related reduction in variability in neural networks. Hum Brain Mapp, 2013. © 2013 Wiley Periodicals, Inc.
Original languageEnglish
Pages (from-to)3025–3035
Number of pages11
JournalHuman Brain Mapping
Volume35
Issue number7
Early online date18 Oct 2013
DOIs
Publication statusPublished - 31 Jul 2014

Fingerprint

Short-Term Memory
Parietal Lobe
Gyrus Cinguli
Prefrontal Cortex
Neuroimaging
Magnetic Resonance Imaging
Brain

Keywords

  • neuroimaging
  • fMRI
  • n-back task
  • dorsolateral prefrontal cortex
  • short-term plasticity
  • parietal
  • anterior cingulate

Cite this

Dima, Danai ; Jogia, Jigar ; Frangou, Sophia. / Dynamic causal modeling of load-dependent modulation of effective connectivity within the verbal working memory network. In: Human Brain Mapping. 2014 ; Vol. 35, No. 7. pp. 3025–3035.
@article{e4c338518a91443cbe797515ca97bafb,
title = "Dynamic causal modeling of load-dependent modulation of effective connectivity within the verbal working memory network",
abstract = "Neuroimaging studies have consistently shown that working memory (WM) tasks engage a distributed neural network that primarily includes the dorsolateral prefrontal cortex, the parietal cortex, and the anterior cingulate cortex. The current challenge is to provide a mechanistic account of the changes observed in regional activity. To achieve this, we characterized neuroplastic responses in effective connectivity between these regions at increasing WM loads using dynamic causal modeling of functional magnetic resonance imaging data obtained from healthy individuals during a verbal n-back task. Our data demonstrate that increasing memory load was associated with (a) right-hemisphere dominance, (b) increasing forward (i.e., posterior to anterior) effective connectivity within the WM network, and (c) reduction in individual variability in WM network architecture resulting in the right-hemisphere forward model reaching an exceedance probability of 99{\%} in the most demanding condition. Our results provide direct empirical support that task difficulty, in our case WM load, is a significant moderator of short-term plasticity, complementing existing theories of task-related reduction in variability in neural networks. Hum Brain Mapp, 2013. {\circledC} 2013 Wiley Periodicals, Inc.",
keywords = "neuroimaging, fMRI, n-back task, dorsolateral prefrontal cortex, short-term plasticity, parietal, anterior cingulate",
author = "Danai Dima and Jigar Jogia and Sophia Frangou",
year = "2014",
month = "7",
day = "31",
doi = "10.1002/hbm.22382",
language = "English",
volume = "35",
pages = "3025–3035",
journal = "Human Brain Mapping",
issn = "1065-9471",
publisher = "Wiley",
number = "7",

}

Dynamic causal modeling of load-dependent modulation of effective connectivity within the verbal working memory network. / Dima, Danai; Jogia, Jigar; Frangou, Sophia.

In: Human Brain Mapping, Vol. 35, No. 7, 31.07.2014, p. 3025–3035.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Dynamic causal modeling of load-dependent modulation of effective connectivity within the verbal working memory network

AU - Dima, Danai

AU - Jogia, Jigar

AU - Frangou, Sophia

PY - 2014/7/31

Y1 - 2014/7/31

N2 - Neuroimaging studies have consistently shown that working memory (WM) tasks engage a distributed neural network that primarily includes the dorsolateral prefrontal cortex, the parietal cortex, and the anterior cingulate cortex. The current challenge is to provide a mechanistic account of the changes observed in regional activity. To achieve this, we characterized neuroplastic responses in effective connectivity between these regions at increasing WM loads using dynamic causal modeling of functional magnetic resonance imaging data obtained from healthy individuals during a verbal n-back task. Our data demonstrate that increasing memory load was associated with (a) right-hemisphere dominance, (b) increasing forward (i.e., posterior to anterior) effective connectivity within the WM network, and (c) reduction in individual variability in WM network architecture resulting in the right-hemisphere forward model reaching an exceedance probability of 99% in the most demanding condition. Our results provide direct empirical support that task difficulty, in our case WM load, is a significant moderator of short-term plasticity, complementing existing theories of task-related reduction in variability in neural networks. Hum Brain Mapp, 2013. © 2013 Wiley Periodicals, Inc.

AB - Neuroimaging studies have consistently shown that working memory (WM) tasks engage a distributed neural network that primarily includes the dorsolateral prefrontal cortex, the parietal cortex, and the anterior cingulate cortex. The current challenge is to provide a mechanistic account of the changes observed in regional activity. To achieve this, we characterized neuroplastic responses in effective connectivity between these regions at increasing WM loads using dynamic causal modeling of functional magnetic resonance imaging data obtained from healthy individuals during a verbal n-back task. Our data demonstrate that increasing memory load was associated with (a) right-hemisphere dominance, (b) increasing forward (i.e., posterior to anterior) effective connectivity within the WM network, and (c) reduction in individual variability in WM network architecture resulting in the right-hemisphere forward model reaching an exceedance probability of 99% in the most demanding condition. Our results provide direct empirical support that task difficulty, in our case WM load, is a significant moderator of short-term plasticity, complementing existing theories of task-related reduction in variability in neural networks. Hum Brain Mapp, 2013. © 2013 Wiley Periodicals, Inc.

KW - neuroimaging

KW - fMRI

KW - n-back task

KW - dorsolateral prefrontal cortex

KW - short-term plasticity

KW - parietal

KW - anterior cingulate

UR - https://onlinelibrary.wiley.com/doi/abs/10.1002/hbm.22382

U2 - 10.1002/hbm.22382

DO - 10.1002/hbm.22382

M3 - Article

C2 - 24142432

VL - 35

SP - 3025

EP - 3035

JO - Human Brain Mapping

JF - Human Brain Mapping

SN - 1065-9471

IS - 7

ER -