Resting-state networks in Alzheimer's disease and Parkinson's disease.

While there is good evidence for altered resting-state networks, particularly the default mode network (DMN), in both Alzheimer's disease (AD) and amnestic mild cognitive impairment preceding AD, there are rather conflicting data on changes in the DMN in Parkinson's disease (PD) and PD with cognitive impairment. This paper will focus on DMN study results, particularly in PD, as assessed by functional MRI.