Marked loss of myelinated nerve fibers in the human brain with age

@article{Marner2003MarkedLO,
  title={Marked loss of myelinated nerve fibers in the human brain with age},
  author={Lisbeth Marner and Jens Randel Nyengaard and Yong Tang and Bente Pakkenberg},
  journal={Journal of Comparative Neurology},
  year={2003},
  volume={462}
}
The white matter is the structure of the brain that declines most with age—almost 30%, but little is known about the age‐effect on the fibers that constitute the white matter. In the present study, the total length of myelinated fibers was measured with a newly developed stereologic method. Specimens came from 36 normal Danes (18 males and 18 females) with an age ranging between 18 and 93 years. Samples were taken systematically and randomly from the white matter, and the biopsy specimens were… Expand
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References

SHOWING 1-10 OF 36 REFERENCES
Age-Induced White Matter Changes in the Human Brain: A Stereological Investigation
TLDR
The findings show that the atrophy of the human white matter during ageing is probably caused by a loss of myelinated fibers with a small diameter. Expand
Age‐Related White Matter Atrophy in the Human Brain
TLDR
The findings show that the age-related decline in brain volume is much more a question of white matter atrophy than of brain cortex atrophy, which could be an indirect indicator of nerve cell loss, since the volume of a nerve cell is much smaller than its myelinated fiber. Expand
A stereological method for estimating the total length and size of myelin fibers in human brain white matter
TLDR
The sampling scheme is designed so that the majority of brain white matter is left intact, thus providing the possibility for resampling and further analysis, and the influence of the postmortem fixation delay on nerve fiber parameters was investigated. Expand
Effects of age on the thickness of myelin sheaths in monkey primary visual cortex
TLDR
It seems that, with age, there is some degeneration of myelin but, at the same time, a continued production of lamellae in the myelin sheaths of old monkeys. Expand
Effects of aging on myelinated nerve fibers in monkey primary visual cortex
TLDR
In monkeys, myelin sheaths of the axons in the vertical bundles of nerve fibers passing through the deeper layers of primary visual cortex show age‐related alterations in their structure, and there is a significant correlation between the breakdown of the myelin and the impairments in cognition exhibited by individual monkeys. Expand
Effects of age on tissues and regions of the cerebrum and cerebellum
TLDR
MR signal alterations in the tissues of older individuals pose challenges to the validity of current methods of tissue segmentation, and should be considered in the interpretation of the results. Expand
Neocortical neuron number in humans: Effect of sex and age
TLDR
Sex and age were the main determinants of the total number of neurons in the human neocortex, whereas body size, per se, had no influence on neuron number. Expand
Age Dependent White Matter Lesions and Brain Volume Changes in Healthy Volunteers
TLDR
The results suggest that with aging central atrophy increases more (relatively) than cortical atrophy. Expand
Age‐related changes in oligodendrocytes in monkey cerebral cortex
  • A. Peters
  • Biology, Medicine
  • The Journal of comparative neurology
  • 1996
TLDR
It is hypothesized that the alterations in the oligodendrocyte‐myelin system lead to changes in the rates of conduction along fibers whose myelin sheaths are affected, and this may be one of the causes of the behavioral changes associated with aging in primates. Expand
White matter changes with normal aging
TLDR
The finding of a highly significant decrease with age in white matter, in the absence of a substantial decrease in gray matter, is consistent with recent neuropathologic reports in humans and nonhuman primates. Expand
...
1
2
3
4
...