Journal ArticleDOI
Life and Death of Neurons in the Aging Brain
John H. Morrison,Patrick R. Hof +1 more
TLDR
The qualitative and quantitative differences between aging and Alzheimer's disease with respect to neuron loss are discussed, and age-related changes in functional and biochemical attributes of hippocampal circuits that might mediate functional decline in the absence of neuron death are explored.Abstract:
Neurodegenerative disorders are characterized by extensive neuron death that leads to functional decline, but the neurobiological correlates of functional decline in normal aging are less well defined. For decades, it has been a commonly held notion that widespread neuron death in the neocortex and hippocampus is an inevitable concomitant of brain aging, but recent quantitative studies suggest that neuron death is restricted in normal aging and unlikely to account for age-related impairment of neocortical and hippocampal functions. In this article, the qualitative and quantitative differences between aging and Alzheimer's disease with respect to neuron loss are discussed, and age-related changes in functional and biochemical attributes of hippocampal circuits that might mediate functional decline in the absence of neuron death are explored. When these data are viewed comprehensively, it appears that the primary neurobiological substrates for functional impairment in aging differ in important ways from those in neurodegenerative disorders such as Alzheimer's disease.read more
Citations
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Journal ArticleDOI
Aging and the myelinated fibers in prefrontal cortex and corpus callosum of the monkey.
Alan Peters,Claire Sethares +1 more
TL;DR: It is proposed that age‐related myelin alterations are ubiquitous and that the correlations between their frequency and impairments in cognition occur because the conduction velocity along the affected nerve fibers is reduced, so that the normal timing sequences within neuronal circuits break down.
Journal ArticleDOI
Genetic neurodegenerative diseases: The human illness and transgenic models
TL;DR: This review provides an overview of transgenic mouse models of familial amyotrophic lateral sclerosis, familial Alzheimer's disease, and Huntington's disease and the emerging insights relevant to the underlying molecular mechanisms of these diseases.
Journal ArticleDOI
Prefrontal Gray and White Matter Volumes in Healthy Aging and Alzheimer Disease
TL;DR: It is likely that AD is different from accelerated aging, as both gray and white matter loss contribute to the decline of prefrontal volume and the gray-white matter ratio that does not differ between YHE and subjects with AD.
Journal ArticleDOI
Effects of aging and sensory loss on glial cells in mouse visual and auditory cortices.
TL;DR: The results suggest that the age-related alteration of glial cells in sensory cortical areas can be accelerated by activity‐driven central mechanisms that result from an age‐related loss of peripheral sensitivity.
Journal ArticleDOI
Brain connectivity in neurodegenerative diseases—from phenotype to proteinopathy
Michela Pievani,Nicola Filippini,Martijn P. van den Heuvel,Stefano F. Cappa,Giovanni B. Frisoni +4 more
TL;DR: This Review aims to summarize current evidence that connectivity biomarkers are associated with upstream and downstream disease processes (molecular pathology and clinical symptoms, respectively) in the major neurodegenerative diseases.
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