کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1904976 | 1534686 | 2012 | 11 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Imaging the default mode network in aging and dementia Imaging the default mode network in aging and dementia](/preview/png/1904976.png)
Although in the last decade brain activation in healthy aging and dementia was mainly studied using task-activation fMRI, there is increasing interest in task-induced decreases in brain activity, termed deactivations. These deactivations occur in the so-called default mode network (DMN). In parallel a growing number of studies focused on spontaneous, ongoing ‘baseline’ activity in the DMN. These resting state fMRI studies explored the functional connectivity in the DMN. Here we review whether normal aging and dementia affect task-induced deactivation and functional connectivity in the DMN. The majority of studies show a decreased DMN functional connectivity and task-induced DMN deactivations along a continuum from normal aging to mild cognitive impairment and to Alzheimer's disease (AD). Even subjects at risk for developing AD, either in terms of having amyloid plaques or carrying the APOE4 allele, showed disruptions in the DMN. While fMRI is a useful tool for detecting changes in DMN functional connectivity and deactivation, more work needs to be conducted to conclude whether these measures will become useful as a clinical diagnostic tool in AD. This article is part of a Special Issue entitled: Imaging Brain Aging and Neurodegenerative disease.
► Aging and dementia: altered deactivation in the brain's default mode network (DMN).
► Altered (mostly decreased) functional connectivity in the DMN in aging and dementia.
► Subjects at risk for dementia: altered deactivation and functional connectivity.
► DMN fMRI is relevant for studying (early) AD and for monitoring progression.
Journal: Biochimica et Biophysica Acta (BBA) - Molecular Basis of Disease - Volume 1822, Issue 3, March 2012, Pages 431–441