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Dynamic functional reorganizations and relationship with working memory performance in healthy aging.

Sala-Llonch R, Arenaza-Urquijo EM, Valls-Pedret C, Vidal-Piñeiro D, Bargalló N, Junqué C, Bartrés-Faz D - Front Hum Neurosci (2012)

Bottom Line: Moreover, resting-state studies have concluded that elders show disconnection or disruption of large-scale functional networks.We found that the disruption of resting-state networks in the elderly coexists with task-related overactivations of certain brain areas and with reorganizations within these functional networks.We concluded that the balanced and plastic reorganization of brain networks underlies successful cognitive aging.

View Article: PubMed Central - PubMed

Affiliation: Departament de Psiquiatria i Psicobiologia Clinica, Facultat de Medicina, Universitat de Barcelona Barcelona, Spain.

ABSTRACT
In recent years, several theories have been proposed in attempts to identify the neural mechanisms underlying successful cognitive aging. Old subjects show increased neural activity during the performance of tasks, mainly in prefrontal areas, which is interpreted as a compensatory mechanism linked to functional brain efficiency. Moreover, resting-state studies have concluded that elders show disconnection or disruption of large-scale functional networks. We used functional MRI during resting-state and a verbal n-back task with different levels of memory load in a cohort of young and old healthy adults to identify patterns of networks associated with working memory and brain default mode. We found that the disruption of resting-state networks in the elderly coexists with task-related overactivations of certain brain areas and with reorganizations within these functional networks. Moreover, elders who were able to activate additional areas and to recruit a more bilateral frontal pattern within the task-related network achieved successful performance on the task. We concluded that the balanced and plastic reorganization of brain networks underlies successful cognitive aging. This observation allows the integration of several theories that have been proposed to date regarding the aging brain.

No MeSH data available.


Summary of the methods used for preprocessing and analysis of fMRI data.
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Figure 1: Summary of the methods used for preprocessing and analysis of fMRI data.

Mentions: We used ICA, as implemented in MELODIC (Beckmann et al., 2005) from FSL, in order to decompose resting-state data into 25 independent components (ICs) which described common spatio-temporal independent patterns of correlated brain activity across the whole group of subjects in the study. Within the 25 ICs obtained, we identified the common resting-state functional networks (Damoiseaux et al., 2008; Smith et al., 2009; van den Heuvel and Hulshoff Pol, 2010), and selected the DMN, and two components corresponding to the right-lateralized and the left-lateralized fronto-parietal networks (right-FPN, and left-FPN). The selection procedure was performed by visual inspection together with template matching with online available data (Smith et al., 2009; Biswal et al., 2010) and with average task-related activation maps obtained from the data-driven analysis (see Figure 1 for a summary of the methods used in the study).


Dynamic functional reorganizations and relationship with working memory performance in healthy aging.

Sala-Llonch R, Arenaza-Urquijo EM, Valls-Pedret C, Vidal-Piñeiro D, Bargalló N, Junqué C, Bartrés-Faz D - Front Hum Neurosci (2012)

Summary of the methods used for preprocessing and analysis of fMRI data.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3369258&req=5

Figure 1: Summary of the methods used for preprocessing and analysis of fMRI data.
Mentions: We used ICA, as implemented in MELODIC (Beckmann et al., 2005) from FSL, in order to decompose resting-state data into 25 independent components (ICs) which described common spatio-temporal independent patterns of correlated brain activity across the whole group of subjects in the study. Within the 25 ICs obtained, we identified the common resting-state functional networks (Damoiseaux et al., 2008; Smith et al., 2009; van den Heuvel and Hulshoff Pol, 2010), and selected the DMN, and two components corresponding to the right-lateralized and the left-lateralized fronto-parietal networks (right-FPN, and left-FPN). The selection procedure was performed by visual inspection together with template matching with online available data (Smith et al., 2009; Biswal et al., 2010) and with average task-related activation maps obtained from the data-driven analysis (see Figure 1 for a summary of the methods used in the study).

Bottom Line: Moreover, resting-state studies have concluded that elders show disconnection or disruption of large-scale functional networks.We found that the disruption of resting-state networks in the elderly coexists with task-related overactivations of certain brain areas and with reorganizations within these functional networks.We concluded that the balanced and plastic reorganization of brain networks underlies successful cognitive aging.

View Article: PubMed Central - PubMed

Affiliation: Departament de Psiquiatria i Psicobiologia Clinica, Facultat de Medicina, Universitat de Barcelona Barcelona, Spain.

ABSTRACT
In recent years, several theories have been proposed in attempts to identify the neural mechanisms underlying successful cognitive aging. Old subjects show increased neural activity during the performance of tasks, mainly in prefrontal areas, which is interpreted as a compensatory mechanism linked to functional brain efficiency. Moreover, resting-state studies have concluded that elders show disconnection or disruption of large-scale functional networks. We used functional MRI during resting-state and a verbal n-back task with different levels of memory load in a cohort of young and old healthy adults to identify patterns of networks associated with working memory and brain default mode. We found that the disruption of resting-state networks in the elderly coexists with task-related overactivations of certain brain areas and with reorganizations within these functional networks. Moreover, elders who were able to activate additional areas and to recruit a more bilateral frontal pattern within the task-related network achieved successful performance on the task. We concluded that the balanced and plastic reorganization of brain networks underlies successful cognitive aging. This observation allows the integration of several theories that have been proposed to date regarding the aging brain.

No MeSH data available.