Canolty and Knight, 2010; Lisman and Jensen, 2013) and has been shown to be vital for working memory in humans (Axmacher et al., 2010). This could suggest a disruption of brain areas known to be affected in AD. We hypothesize that the decreased gamma/theta CFC in pMCI is associated with a network dysfunction but possibly not directly associated with atrophy since no correlation was found with total tau. The lack of any electrode-specific changes between pMCI and sMCI could indicate that this is more related to global dysfunction and less specifically to the temporal lobes. In addition, studies implementing either an N-back task (Goodman et al., 2018) or an auditory oddball paradigm (Dimitriadis et al., 2015) found more pronounced results, which may indicate that the difference in CFC is larger during a task. As a diagnostic tool in AD and MCI, this suggests that gamma/theta CFC should be implemented during a task. Other EEG markers of progression have been suggested, and decreased spectral beta power has been the most commonly reported (Jelic et al., 2000; Poil et al., 2013; Musaeus et al., 2018b). This study suggests that gamma/theta CFC may serve as a marker of progression but has some limitations
