Increased functional connectivity between nucleus basalis of Meynert and amygdala in cognitively intact elderly along the Alzheimer’s continuum

Structural Degeneration of the Nucleus basalis of Meynert in Mild Cognitive Impairment and Alzheimer’s Disease – Evidence from an MRI-based Meta-Analysis

“…With regard to AD, a longitudinal study in humans could show that amygdala degeneration and abnormal memory-related alpha oscillations, as measured with electroencephalography (EEG), predict the conversion to AD (Prieto del Val et al, 2016). Further, fMRI based functional connectivity between the NbM and amygdala during resting state was increased with neuropathology as indicated by amyloid and tau PET (Zeng et al, 2022). This is in line with other PET studies on the spread of amyloid-β and tau (Insel et al, 2020), as well as MRI studies in MCI and AD showing that NbM atrophy covaries with atrophy in innervating regions, including the amygdala (Cantero et al, 2016; Schmitz et al, 2018).…”

“…by including preclinical AD cases in the group of healthy controls), the AT(N) framework, which incorporates amyloid-beta (A), tau (T), and neurodegenerative (N), could have been used (Jack et al, 2018). However, in most studies, these markers were not assessed, and larger sample sizes would be necessary to include at least three groups (A-T-, A+T-, A+T+), with typically imbalanced distributions (see, e.g., Zeng et al (2022)). Additionally, other forms of dementia were excluded based on the specified exclusion criteria in BrainMap that were validated by cross-checking the original literature.…”