Specifically Progressive Deficits of Default Mode Network Inamnestic Type Mild Cognitive Cimpairment: a Follow-up Study

摘要

Objective. Mild cognitive impairment (MCI) is believed to be an intermediate state between normal aging and dementia. Amnestic MCI (aMCI) is assumed if the impairment involves memory domain that is proposed as a risk factor for Alzheimer's disease (AD), whereas non-aMCI concerned to non-memory deficits are often conceptualized as the prodromal phase for other causes of dementia. Early detection of disease processes of aMCI which presage the development of AD and a better understanding of the functional markers would be of benefit in terms of determining intervention and management strategy and likely prognosis. Images of amyloid deposition taken at the earliest stages of AD showed a distribution that is remarkably similar to the anatomy of default mode network (DMN), and increased amyloid deposition is associated with aberrant DMN activity and reduced functional connectivity within the DMN in AD patients, implying that AD pathology forms may be preferentially throughout the DMN. However, longitudinal studies of this network have not been reported in aMCI and identifying markers of DMN for aMCI expected to convert to AD would be of considerable interest.