of APOE-4 on AD functional connectivity. Kramer et al. in an EEG synchronization likelihood study assessed APOE-4 effects on functional connectivity across patients with AD and subjects with subjective memory complaints who served as controls. They noted that among APOE-4 carriers, the patients had decreased alpha connectivity compared with controls, although synchronization likelihood values were significantly higher in carriers vs. noncarriers in both groups. This led to the suggestion that the effects of AD and APOE-4 on global functional connectivity are independent and opposite [21]. The findings of our work cannot be directly compared with those of Kramer et al. [21] as they used averaged scores of synchronization likelihood values of all electrodes for each frequency band to measure global connectivity. Therefore, the topographic distribution of the compromised networks could not be assessed. Nevertheless, the two studies identified abnormalities in alpha band as neural activity underlying APOE-4-related connectivity deficits in AD.
