Related Experiment Video
Updated: Jun 19, 2026

Visualizing Axonal Growth Cone Collapse and Early Amyloid β Effects in Cultured Mouse Neurons
Published on: October 30, 2018
Amyloid plaques disrupt resting state default mode network connectivity in cognitively normal elderly
Yvette I Sheline1, Marcus E Raichle, Abraham Z Snyder
1Department of Psychiatry, Washington University School of Medicine, St. Louis, Missouri, USA. yvette@npg.wustl.edu
Alzheimer's disease (AD) amyloid plaques disrupt brain connectivity even before cognitive decline. Resting-state fMRI detects these early changes in cognitively normal individuals with amyloid deposition.
Area of Science:
- Neuroscience
- Alzheimer's Disease Research
- Brain Imaging
Background:
- Alzheimer's disease (AD) is associated with disrupted default mode network (DMN) functional connectivity, potentially due to amyloid-beta (Abeta) plaque neurotoxicity.
- Investigating Abeta plaque effects on functional connectivity in cognitively normal individuals is crucial for understanding early AD pathogenesis.
Purpose of the Study:
- To determine if Abeta amyloid plaques impact resting-state functional connectivity in cognitively normal individuals.
- To identify early pathological changes associated with preclinical amyloid deposition.
Main Methods:
- Comparison of Alzheimer's disease (AD) patients (n=35) with cognitively normal participants (n=68).
- Subdivision of cognitively normal participants into those with (PIB+) and without (PIB-) brain amyloid deposition using Pittsburgh Compound-B (PIB) PET imaging.
- Analysis of resting-state functional magnetic resonance imaging (fMRI) data to assess functional connectivity.
Main Results:
- Cognitively normal individuals with brain amyloid (PIB+) showed significant differences in precuneus functional connectivity compared to those without amyloid (PIB-).
- Affected regions included the hippocampus, parahippocampus, anterior cingulate, dorsal cingulate, gyrus rectus, superior precuneus, and visual cortex.
- Connectivity differences in PIB+ individuals mirrored those observed in the AD group.
Conclusions:
- Resting-state fMRI can detect alterations in functional connectivity in cognitively normal individuals with brain amyloid deposition.
- These findings suggest that Abeta toxicity can manifest as altered brain connectivity prior to cognitive or behavioral symptoms.
- Early detection of Abeta-related neurotoxicity is possible through resting-state fMRI analysis.
More Related Videos
14:57Preparation of Acute Hippocampal Slices from Rats and Transgenic Mice for the Study of Synaptic Alterations during Aging and Amyloid Pathology
Published on: March 23, 2011
08:27Establishment of a Valuable Mimic of Alzheimer's Disease in Rat Animal Model by Intracerebroventricular Injection of Composited Amyloid Beta Protein
Published on: July 29, 2018
Related Concept Videos
Alzheimer Disease ll: Pathophysiology
Amyloid Fibrils
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
Amyloid Fibrils
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
Alzheimer Disease l: Introduction
Alzheimer's Disease: Overview
The clinical diagnosis of AD hinges on the presence of memory and other cognitive impairments. Biomarkers, such as changes in Aβ and tau...
Dementia l: Introduction