White Matter Changes Compromise Prefrontal Cortex Function in Healthy Elderly Individuals

@article{Nordahl2006WhiteMC,
  title={White Matter Changes Compromise Prefrontal Cortex Function in Healthy Elderly Individuals},
  author={Christine Wu Nordahl and Charan Ranganath and Andrew P. Yonelinas and Charles DeCarli and Evan Fletcher and William J. Jagust},
  journal={Journal of Cognitive Neuroscience},
  year={2006},
  volume={18},
  pages={418-429}
}
Changes in memory function in elderly individuals are often attributed to dysfunction of the prefrontal cortex (PFC). One mechanism for this dysfunction may be disruption of white matter tracts that connect the PFC with its anatomical targets. Here, we tested the hypothesis that white matter degeneration is associated with reduced prefrontal activation. We used white matter hyperintensities (WMH), a magnetic resonance imaging (MRI) finding associated with cerebrovascular disease in elderly… 
Episodic memory function is associated with multiple measures of white matter integrity in cognitive aging
TLDR
The results suggest that white matter injury to multiple pathways, including connections of frontal and temporal cortex and frontal-subcortical white matter tracts, plays a critical role in memory differences seen in older individuals.
Late life cognitive control deficits are accentuated by white matter disease burden.
TLDR
The results suggest that age-related goal maintenance impairments and associated dorsolateral prefrontal cortex dysfunction may partly reflect incipient white matter disease of interconnected cognitive networks.
White Matter Hyperintensities among Older Adults Are Associated with Futile Increase in Frontal Activation and Functional Connectivity during Spatial Search
TLDR
White matter hyperintensities may lead to subtle attentional network dysfunction, potentially through impaired frontal-parietal and frontal interhemispheric connectivity, suggesting that clinically silent white matter biomarkers of vascular and inflammatory injury can contribute to differences in search performance and brain function in aging, and likely contribute to advanced age-related impairments in cognitive control.
Reduced Functional Reserve in Patients with Age-Related White Matter Changes: A Preliminary fMRI Study of Working Memory
TLDR
Findings suggest that even clinically silent ARWMC may affect cognitive processing and lead to compensatory activation during cognitive tasks, which can be interpreted as a reduction of functional reserve and may pose a risk for cognitive decline in patients.
Structural and functional differences in medial prefrontal cortex underlies distractibility and suppression deficits in aging
TLDR
The neural basis of distraction’s negative impact on WM and the impairment in neural suppression in older adults are evaluated by performing structural and functional MRIs while older participants engage in tasks that require remembering relevant visual stimuli in the context of overlapping irrelevant stimuli.
Abnormal functional connectivity density in patients with ischemic white matter lesions
TLDR
It is found that patients with ischemic WMLs showed reduced short-range FCD in the temporal cortex, primary motor cortex, and subcortical region, which may account for inadequate top-down attention, impaired motor, memory, and executive function associated with W MLs.
Frontal lobes and aging : Deterioration and Compensation
TLDR
Findings in the first crop of positron emotion tomography studies challenged the standard assumption that aging is associated with a simple pattern of cognitive and neural decline, and supported the notion that cognitive processing in the aging brain is not just a weaker version of cognitiveprocessing in the young brain, it is different.
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 86 REFERENCES
White matter lesions impair frontal lobe function regardless of their location
TLDR
The frontal lobes are most severely affected by SIVD, and WMHs are more abundant in the frontal region, regardless of where in the brain these WMH's are located, they are associated with frontal hypometabolism and executive dysfunction.
On the Involvement of Prefrontal Networks in Cognitive Ageing
Evidence for cortical “disconnection” as a mechanism of age-related cognitive decline
TLDR
Findings provide direct evidence that white matter tract disruption occurs in normal aging and would be consistent with the cortical disconnection hypothesis of age-related cognitive decline and provide a plausible structural basis for selective loss of executive functions.
Selective aging of the human cerebral cortex observed in vivo: differential vulnerability of the prefrontal gray matter.
TLDR
Small but consistent rightward asymmetry was found in the whole cerebral hemispheres, superior parietal, fusiform and orbito-frontal cortices, postcentral and prefrontal white matter, and in the parietal white matter.
Brain structure and cognition in a community sample of elderly Latinos
TLDR
Reductions in hippocampal volume may be present before dementia but not until cognitive impairment is relatively severe, and interactions between vascular and degenerative processes may be important determinants of dementia.
Cognitive Neuroscience of Aging
  • C. Grady
  • Psychology, Biology
    Annals of the New York Academy of Sciences
  • 2008
TLDR
Findings have provided rather convincing support for the idea that overrecruitment can be compensatory in the elderly, although not all age increases can be interpreted as compensatory, and some are more indicative of neural inefficiency.
The cognitive correlates of white matter abnormalities in normal aging: a quantitative review.
TLDR
Results indicate that white matter abnormalities observed on MR images are associated with attenuated performance on tasks of processing speed, immediate and delayed memory, executive functions, and indices of global cognitive functioning, and there was no significant link between the white matter hyperintensities and psychometric indices of intelligence or fine motor performance.
Hypertension and the brain: vulnerability of the prefrontal regions and executive functions.
TLDR
Even controlled hypertension may be associated with deficits in brain structure and cognition, warranting further study.
...
1
2
3
4
5
...