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Updated: Jun 21, 2026
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Visualizing Axonal Growth Cone Collapse and Early Amyloid β Effects in Cultured Mouse Neurons
Published on: October 30, 2018
Amyloid deposition is associated with impaired default network function in older persons without dementia
Reisa A Sperling1, Peter S Laviolette, Kelly O'Keefe
1Center for Alzheimer Research and Treatment, Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA. reisa@rics.bwh.harvard.edu
Neuron
|July 31, 2009
Summary
Alzheimer's disease (AD) pathology, marked by amyloid beta-protein deposition, is linked to abnormal brain network activity in older adults. This neural dysfunction occurs even before cognitive symptoms appear, suggesting early AD stages.
Area of Science:
- Neuroscience
- Neurology
- Medical Imaging
Background:
- Alzheimer's disease (AD) is linked to functional changes in brain networks supporting memory.
- The default network, particularly posterior regions like the precuneus, is vulnerable to amyloid beta-protein deposition in AD.
- Amyloid deposition is a key pathological hallmark of Alzheimer's disease.
Purpose of the Study:
- To investigate the association between in vivo amyloid deposition and default network functional activity.
- To examine neural dysfunction in asymptomatic and minimally impaired older individuals with amyloid pathology.
- To support the hypothesis that amyloid pathology indicates early stages of AD in cognitively intact individuals.
Main Methods:
- Utilized in vivo amyloid imaging to quantify amyloid beta-protein deposition.
- Employed functional magnetic resonance imaging (fMRI) to assess default network activity.
- Studied asymptomatic and minimally impaired older individuals.
Main Results:
- High levels of amyloid deposition correlated with aberrant default network fMRI activity.
- The observed pattern of neural dysfunction resembles that reported in Alzheimer's disease patients.
- Amyloid pathology was associated with neural dysfunction in memory-related brain regions.
Conclusions:
- Amyloid pathology is directly linked to neural dysfunction in brain regions critical for memory.
- Cognitively intact older individuals with amyloid pathology may represent an early stage of Alzheimer's disease.
- Findings support the hypothesis of preclinical AD in individuals with amyloid evidence.
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