Plasticity of the Right-Lateralized Cognitive Reserve Network in Ageing

Background: Cognitive reserve (CR) is an important protective factor for Alzheimer’s disease (AD), yet its mechanism has not been fully elucidated. Objective: To explore the effect of CR on resting and dynamic brain intrinsic activity in patients with mild cognitive impairment (MCI). Methods: 65 amyloid-β PET-negative (Aβ-) normal controls (NC) and 30 amyloid-β PET-positive (Aβ+) MCI patients underwent resting-state functional magnetic resonance imaging were included from Alzheimer’s Disease Neuroimaging Initiative. According to the years of education, the subjects were divided into high education group and low education group. A two-way analysis of variance was employed for the fractional amplitude of low-frequency fluctuation (fALFF) and dynamic fALFF (dfALFF) comparisons among the four groups. Moreover, the interaction effect of neuroimaging×pathology on clinical cognitive function was tested with linear regression analysis. Results: The value of fALFF in the left prefrontal lobe was increased in Aβ+ MCI patients compared to Aβ- NC. The significant interactive effect between disease state and education (binary factor) was observed in the right parahippocampal gyrus (PHG) for fALFF, the right PHG and the right inferior parietal lobule for dfALFF. While no significant results between education (continuous factor) and brain activity was found in voxel-by-voxel analysis. For MCI patients, a significant fluorodeoxyglucose hypometabolic convergence index×right PHG dfALFF interaction was found, indicating the maintenance of executive function at higher levels of dfALFF in the right PHG. Conclusion: High CR can alleviate the impairment of hypometabolism on executive function in MCI patients, which is partially achieved by regulating the dynamic brain activity in the right PHG.

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Associations between EEG functional brain connectivity and a cognitive reserve proxy in healthy older adults

10.1101/625608 ◽

2019 ◽

Author(s):

Bahar Moezzi ◽

Louise M. Lavrencic ◽

Mitchell R. Goldsworthy ◽

Scott Coussens ◽

Hannah A.D. Keage

Keyword(s):

Prefrontal Cortex ◽

Functional Connectivity ◽

Cognitive Reserve ◽

Medium Effect ◽

Theta Band ◽

Healthy Older Adults ◽

Eyes Closed ◽

Medium Effect Size ◽

Eyes Open ◽

The Right

AbstractCognitive reserve is a concept that explains individual differences in vulnerability to cognitive impairment due to age and dementia-related brain changes. Mechanisms underlying the cognitive reserve effect are poorly understood. We investigated associations between a comprehensive cognitive reserve proxy (Lifetime Experiences Questionnaire/LEQ) and functional connectivity of the prefrontal cortex across the whole scalp, covarying for the level of current cognitive functioning (Addenbrookes Cognitive Examination Revised/ACE-R), using multiblock parallel and orthogonalized partial least squares regression. EEG data were collected from 34 healthy older adults (63 to 83 years) in eyes-open and eyes-closed resting-states, and during 0-back and 1-back tasks. Functional connectivity was estimated using imaginary coherence in the theta and alpha frequency bands, as these bands have been heavily implicated in cognitive ageing, attention and executive function. We found three clusters of electrodes where the absolute values of the regression coefficient were above threshold when covarying for ACE-R: (1) a cluster approximating the right frontocentral region during the eyes-open condition in the theta band with seed electrodes approximating the left prefrontal cortex with positive associations of medium effect size; (2) a cluster approximating the right parietotemporal region during the 0-back task in the theta band with seed electrodes approximating the right prefrontal cortex with negative associations of medium to large effect sizes; and (3) a cluster approximating the occipitoparietal region in the eyes-closed condition in the alpha band with seed electrodes approximating the left prefrontal cortex with negative associations of medium effect size. These relationships between a cognitive reserve proxy and functional connectivity, within key networks and frequency bands associated with attention and executive function, may reflect greater neural capacity and efficiency.

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IDENTIFYING A TASK-INVARIENT COGNITIVE RESERVE NETWORK

Alzheimer s & Dementia ◽

10.1016/j.jalz.2017.07.481 ◽

2017 ◽

Vol 13 (7) ◽

pp. P1445-P1446

Author(s):

Yaakov Stern ◽

Christian Habeck

Keyword(s):

Cognitive Reserve ◽

Reserve Network

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A task-invariant cognitive reserve network

NeuroImage ◽

10.1016/j.neuroimage.2018.05.033 ◽

2018 ◽

Vol 178 ◽

pp. 36-45 ◽

Cited By ~ 39

Author(s):

Yaakov Stern ◽

Yunglin Gazes ◽

Qolomreza Razlighi ◽

Jason Steffener ◽

Christian Habeck

Keyword(s):

Cognitive Reserve ◽

Reserve Network

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Identifying a task-invariant cognitive reserve network using task potency

NeuroImage ◽

10.1016/j.neuroimage.2020.116593 ◽

2020 ◽

Vol 210 ◽

pp. 116593

Author(s):

A.C. van Loenhoud ◽

C. Habeck ◽

W.M. van der Flier ◽

R. Ossenkoppele ◽

Y. Stern

Keyword(s):

Cognitive Reserve ◽

Reserve Network

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Resting-state electroencephalographic correlates of cognitive reserve: Moderating the age-related decline in cognitive function

10.31234/osf.io/wc82m ◽

2022 ◽

Author(s):

Ana Bujan ◽

Adriana Sampaio ◽

Diego Pinal

Keyword(s):

Resting State ◽

Cognitive Reserve ◽

Right Hemisphere ◽

Current Source ◽

Neural Correlates ◽

Cognitive Status ◽

Neuroprotective Effects ◽

Age Related ◽

The Right ◽

The Relationship

Measurement of cognitive reserve (CR) is a matter of constant reviews and developments due to the difficulty to assess it directly, being socio-behavioral indexes used as indirect proxies. An effort to unravel the neural correlates underlying CR seems mandatory, and strongly supported by the neuroscientific literature. Neurophysiological measures through electroencephalography (EEG) have proven to be a promising, almost inexpensive method to study the CR neural correlates. In line with the recommendations of Stern et al. (2020), the aim of the present study has been to demonstrate that resting-state EEG measures may moderate the relationship between age-related brain changes and cognitive status; thus, constituting an objective neural index of CR.Our results show that two resting-state EEG measures, delta current source density in the occipital region and beta 2 connectivity between limbic and occipital regions in the right hemisphere, moderate the relation between age and cognitive performance, indexing neuroprotective effects on cognition during the aging process. These results not only shed light on the neural mechanisms involved in CR but also allow us to propose features to be taken into account in order to enhance the results of interventions to delay the onset of cognitive deficits.

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Investor-State Dispute Settlement under NAFTA Chapter 11: The Shape of Things to Come?

Canadian Yearbook of international Law/Annuaire canadien de droit international ◽

10.1017/s0069005800006652 ◽

1998 ◽

Vol 35 ◽

pp. 263-290

Author(s):

J. Anthony VanDuzer

Keyword(s):

Free Trade Agreement ◽

Dispute Settlement ◽

Trade Agreement ◽

Minimum Standards ◽

The North ◽

State Behaviour ◽

Nafta Chapter 11 ◽

To Come ◽

The Right

SummaryRecently, there has been a proliferation of international agreements imposing minimum standards on states in respect of their treatment of foreign investors and allowing investors to initiate dispute settlement proceedings where a state violates these standards. Of greatest significance to Canada is Chapter 11 of the North American Free Trade Agreement, which provides both standards for state behaviour and the right to initiate binding arbitration. Since 1996, four cases have been brought under Chapter 11. This note describes the Chapter 11 process and suggests some of the issues that may arise as it is increasingly resorted to by investors.

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What face familiarity feelings say about the lateralization of specific entities within the core system

Behavioral and Brain Sciences ◽

10.1017/s0140525x19001778 ◽

2019 ◽

Vol 42 ◽

Author(s):

Guido Gainotti

Keyword(s):

Temporal Lobe ◽

Memory System ◽

Core System ◽

The Core ◽

Memory Traces ◽

Specific Memory ◽

Target Article ◽

Temporal Structures ◽

The Right

Abstract The target article carefully describes the memory system, centered on the temporal lobe that builds specific memory traces. It does not, however, mention the laterality effects that exist within this system. This commentary briefly surveys evidence showing that clear asymmetries exist within the temporal lobe structures subserving the core system and that the right temporal structures mainly underpin face familiarity feelings.

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Address By The Right Honourable The Earl of Balfour, Chancellor of the University of Cambridge

Transactions of the International Astronomical Union ◽

10.1017/s0251107x00012670 ◽

1925 ◽

Vol 2 ◽

pp. 146-149

Keyword(s):

University Of Cambridge ◽

The Right ◽

The University

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Study of charge transfer in FeTi

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075270 ◽

1983 ◽

Vol 41 ◽

pp. 296-297

Author(s):

J. Taft∅

Keyword(s):

Charge Transfer ◽

Charge Distribution ◽

Electron Scattering ◽

Periodic System ◽

Electron Distribution ◽

Scattering Amplitude ◽

Transition Elements ◽

Hartree Fock ◽

Cscl Structure ◽

The Right

It is well known that for reflections corresponding to large interplanar spacings (i.e., sin θ/λ small), the electron scattering amplitude, f, is sensitive to the ionicity and to the charge distribution around the atoms. We have used this in order to obtain information about the charge distribution in FeTi, which is a candidate for storage of hydrogen. Our goal is to study the changes in electron distribution in the presence of hydrogen, and also the ionicity of hydrogen in metals, but so far our study has been limited to pure FeTi. FeTi has the CsCl structure and thus Fe and Ti scatter with a phase difference of π into the 100-ref lections. Because Fe (Z = 26) is higher in the periodic system than Ti (Z = 22), an immediate “guess” would be that Fe has a larger scattering amplitude than Ti. However, relativistic Hartree-Fock calculations show that the opposite is the case for the 100-reflection. An explanation for this may be sought in the stronger localization of the d-electrons of the first row transition elements when moving to the right in the periodic table. The tabulated difference between fTi (100) and ffe (100) is small, however, and based on the values of the scattering amplitude for isolated atoms, the kinematical intensity of the 100-reflection is only 5.10-4 of the intensity of the 200-reflection.

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