6533b86cfe1ef96bd12c8cea
RESEARCH PRODUCT
The default mode network and the working memory network are not anti-correlated during all phases of a working memory task
Marta ReDavid Edmund Johannes LindenAlexander SackFrancesco Di SalleGiancarlo ValenteTommaso PiccoliFabrizio Espositosubject
MaleCingulate cortexComputer scienceFunctional magnetic resonance imagingCINGULATE CORTEX0302 clinical medicinePrefrontal cortexALZHEIMERSDefault mode networkCerebral CortexDefault mode network; female; Functional magnetic resonance imaging; Working memoryMultidisciplinarymedicine.diagnostic_testArtificial neural networkQ05 social sciencesRCognitionHuman brainFUNCTIONAL CONNECTIVITYFLUCTUATIONSMagnetic Resonance ImagingMemory Short-Termmedicine.anatomical_structurefemaleCerebral cortexConnectomeMedicineSettore MED/26 - NeurologiaAlzheimer's diseasedefault mode network; working memory; functional magnetic resonance imaging; functional connectivity; Brain networksResearch ArticleHumanCognitive psychologyAdultBrain networksScienceRETRIEVALPosterior parietal cortex050105 experimental psychologyYoung Adult03 medical and health sciencesPARIETAL CORTEXTask-positive networkEncoding (memory)ConnectomemedicineHumans0501 psychology and cognitive sciencesMODULATIONBRAIN-FUNCTIONResting state fMRIWorking memoryWorking memorymedicine.diseaseR1COMPONENTDefault mode networkRESTING-STATEFunctional magnetic resonance imaging030217 neurology & neurosurgerydescription
INTRODUCTION:\ud \ud The default mode network and the working memory network are known to be anti-correlated during sustained cognitive processing, in a load-dependent manner. We hypothesized that functional connectivity among nodes of the two networks could be dynamically modulated by task phases across time.\ud METHODS:\ud \ud To address the dynamic links between default mode network and the working memory network, we used a delayed visuo-spatial working memory paradigm, which allowed us to separate three different phases of working memory (encoding, maintenance, and retrieval), and analyzed the functional connectivity during each phase within and between the default mode network and the working memory network networks.\ud RESULTS:\ud \ud We found that the two networks are anti-correlated only during the maintenance phase of working memory, i.e. when attention is focused on a memorized stimulus in the absence of external input. Conversely, during the encoding and retrieval phases, when the external stimulation is present, the default mode network is positively coupled with the working memory network, suggesting the existence of a dynamically switching of functional connectivity between "task-positive" and "task-negative" brain networks.\ud CONCLUSIONS:\ud \ud Our results demonstrate that the well-established dichotomy of the human brain (anti-correlated networks during rest and balanced activation-deactivation during cognition) has a more nuanced organization than previously thought and engages in different patterns of correlation and anti-correlation during specific sub-phases of a cognitive task. This nuanced organization reinforces the hypothesis of a direct involvement of the default mode network in cognitive functions, as represented by a dynamic rather than static interaction with specific task-positive networks, such as the working memory network.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2015-04-07 |