scholarly journals Episodic memory in aspects of brain information transfer by resting-state network topology

2021 ◽  
Author(s):  
Tianyi Yan ◽  
Gongshu Wang ◽  
Li Wang ◽  
Tiantian Liu ◽  
Ting Li ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Episodic Memory ◽  
Resting State ◽  
Information Transfer ◽  
Memory Performance ◽  
Structural Connectivity ◽  
Transfer Mechanism ◽  
Resting State Functional Connectivity ◽  
Cognitive Information ◽  
Encoding And Retrieval

Studies suggest that resting-state functional connectivity conveys cognitive information; also, activity flow mediates cognitive information transfer. However, the exact mechanism of interregional interactions underlying episodic memory remains unclear. We performed a combined analysis of task-evoked activity and resting-state functional connectivity by activity flow mapping to estimate the information transfer mechanism of episodic memory. We found that the cognitive control and attentional networks were the most recruited structures in information transfers during both encoding and retrieval processes; these networks were correlated with task-evoked activation. Differences in information transfer intensity between encoding and retrieval mainly existed in the visual, somatomotor and hippocampal systems. Furthermore, information transfer showed high predictive power for episodic memory ability and mediated relationships between task-evoked activation and memory performance. Additional analysis indicated that structural connectivity had a transportive role in information transfer. Finally, our study presented the information transfer mechanism of episodic memory from multiple neural perspectives.

scholarly journals Effects of amnesia on processing in the hippocampus and default mode network during a naturalistic memory task: a case study

2018 ◽  
Author(s):  
Christiane Oedekoven ◽  
James L. Keidel ◽  
Stuart Anderson ◽  
Angus Nisbet ◽  
Chris Bird
Keyword(s):  
Functional Connectivity ◽  
Episodic Memory ◽  
Memory Performance ◽  
Memory Task ◽  
Structural Mri ◽  
Brain Regions ◽  
Left Hippocampus ◽  
Cortical Regions ◽  
The Right ◽  
Encoding And Retrieval

Despite their severely impaired episodic memory, individuals with amnesia are able to comprehend ongoing events. Online representations of a current event are thought to be supported by a network of regions centred on the posterior midline cortex (PMC). By contrast, episodic memory is widely believed to be supported by interactions between the hippocampus and these cortical regions. In this MRI study, we investigated the encoding and retrieval of lifelike events (video clips) in a patient with severe amnesia likely resulting from a stroke to the right thalamus, and a group of 20 age-matched controls. Structural MRI revealed grey matter reductions in left hippocampus and left thalamus in comparison to controls. We first characterised the regions activated in the controls while they watched and retrieved the videos. There were no differences in activation between the patient and controls in any of the regions. We then identified a widespread network of brain regions, including the hippocampus, that were functionally connected with the PMC in controls. However, in the patient there was a specific reduction in functional connectivity between the PMC and a region of left hippocampus when both watching and attempting to retrieve the videos. A follow up analysis revealed that in controls the functional connectivity between these regions when watching the videos was correlated with memory performance. Taken together, these findings support the view that the interactions between the PMC and the hippocampus enable the encoding and retrieval of multimodal representations of the contents of an event.

scholarly journals Predicting human resting-state functional connectivity from structural connectivity

2009 ◽  
Vol 106 (6) ◽  
pp. 2035-2040 ◽  
Author(s):  
C. J. Honey ◽  
O. Sporns ◽  
L. Cammoun ◽  
X. Gigandet ◽  
J. P. Thiran ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Resting State ◽  
Structural Connectivity ◽  
Resting State Functional Connectivity

scholarly journals 3046 Reduced structural and functional connectivity in infants with prenatal opioid exposure

2019 ◽  
Vol 3 (s1) ◽  
pp. 52-52
Author(s):  
Stephanie Merhar ◽  
Adebayo Braimah ◽  
Traci Beiersdorfer ◽  
Brenda Poindexter ◽  
Nehal Parikh
Keyword(s):  
White Matter ◽  
Functional Connectivity ◽  
Fractional Anisotropy ◽  
Behavioral Problems ◽  
Resting State ◽  
Maternal Education ◽  
Structural Connectivity ◽  
Resting State Functional Connectivity ◽  
Small Pilot Study ◽  
Sensorimotor Network

OBJECTIVES/SPECIFIC AIMS:. This study aims to understand the effects of prenatal opioid exposure on structural and functional connectivity in the neonatal brain. Our central hypothesis is that infants with prenatal opioid exposure will have decreased structural and functional connectivity as compared to non-exposed controls. Our overarching goal is to improve neurodevelopmental and behavioral outcomes in infants with prenatal opioid exposure. METHODS/STUDY POPULATION:. Infants with prenatal opioid exposure were recruited from 2 birth hospitals in our area. Control infants were recruited from the larger community. Infants underwent MRI between 4-6 weeks of age in the Cincinnati Children’s Hospital Imaging Research Center. MRI sequences included 3D structural T1 and T2-weighted imaging, resting state functional connectivity MRI, and multi-shell DTI (36 directions at b=800 and 68 directions at b=2000). Tract-based spatial statistics (TBSS) was used to identify differences in fractional anisotropy (a measure of white matter integrity) between groups. Group independent component analysis was used to identify differences in resting-state networks between groups RESULTS/ANTICIPATED RESULTS:. There were 5 subjects enrolled in the study with evaluable imaging, 3 infants with prenatal opioid exposure and 2 unexposed controls. Structural MRI was normal in all cases. Infants with prenatal opioid exposure had reduced structural connectivity as measured by fractional anisotropy (FA) in the genu and splenium of the corpus callosum as compared with controls. The orange/red color represents areas in which the FA of the opioid-exposed group was lower than controls and green represents the white matter skeleton common to both groups. Infants with prenatal opioid exposure also had significantly reduced within-network functional connectivity strength (z-transformed partial correlation coefficient 0.358 vs 0.199, p = 0.03) in the sensorimotor network as compared with controls. DISCUSSION/SIGNIFICANCE OF IMPACT:. In this small pilot study, both structural and functional connectivity were reduced in opioid-exposed infants compared with controls. This data suggests that differences in structural and functional connectivity may underlie the later developmental and behavioral problems seen in opioid-exposed children. These findings must be validated in a larger population with correction for confounding factors such as maternal education

IC-P-095: Increased resting state functional connectivity associated with episodic memory impairment in mild cognitive impairment

2015 ◽  
Vol 11 (7S_Part_2) ◽  
pp. P66-P66
Author(s):  
Yifei Zhang ◽  
Miguel Ángel Araque Caballero ◽  
Benno Gesierich ◽  
Alexander N.W. Taylor ◽  
Lee Simon-Vermot ◽  
...  
Keyword(s):  
Cognitive Impairment ◽  
Mild Cognitive Impairment ◽  
Functional Connectivity ◽  
Episodic Memory ◽  
Resting State ◽  
Memory Impairment ◽  
Resting State Functional Connectivity

scholarly journals Predicting MEG resting-state functional connectivity from microstructural information

2021 ◽  
pp. 1-42
Author(s):  
Eirini Messaritaki ◽  
Sonya Foley ◽  
Simona Schiavi ◽  
Lorenzo Magazzini ◽  
Bethany Routley ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Fractional Anisotropy ◽  
Shortest Path ◽  
Resting State ◽  
Path Length ◽  
Structural Connectivity ◽  
Imaging Data ◽  
Resting State Functional Connectivity ◽  
Brain Microstructure ◽  
Functional Mechanisms

Understanding how human brain microstructure influences functional connectivity is an important endeavor. In this work, magnetic resonance imaging data from ninety healthy participants were used to calculate structural connectivity matrices using the streamline count, fractional anisotropy, radial diffusivity and a myelin measure (derived from multi-component relaxometry) to assign connection strength. Unweighted binarized structural connectivity matrices were also constructed. Magnetoencephalography resting-state data from those participants were used to calculate functional connectivity matrices, via correlations of the Hilbert envelopes of beamformer timeseries in the delta, theta, alpha and beta frequency bands. Non-negative matrix factorization was performed to identify the components of the functional connectivity. Shortest-path-length and search-information analyses of the structural connectomes were used to predict functional connectivity patterns for each participant. The microstructure-informed algorithms predicted the components of the functional connectivity more accurately than they predicted the total functional connectivity. This provides a methodology to understand functional mechanisms better. The shortest-path-length algorithm exhibited the highest prediction accuracy. Of the weights of the structural connectivity matrices, the streamline count and the myelin measure gave the most accurate predictions, while the fractional anisotropy performed poorly. Overall, different structural metrics paint very different pictures of the structural connectome and its relationship to functional connectivity.

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