The connectivity pattern of patients with AD, compared with controls, was characterized by reduced alpha2 lagged phase synchronization of the medial frontal and medial parietal region with the temporal and inferior parietal cortex (t max = −3.56, p = 0.037 corrected). In addition, there was increased lagged phase synchronization in the theta band, involving mainly temporal and frontal connections (t max = 5.06, p = 0.0032 corrected) (Fig. 4). In particular, there was decreased alpha2 connectivity of the midcentral (medial frontal) and midparietal (precuneus) region with the left posterior temporal cortex, and bilaterally with the inferior parietal cortex. Increases in theta connectivity were seen specifically between the left temporal cortex and prefrontal and central areas. Increased theta connectivity also affected right parieto-temporal and fronto-occipital regions as well as interhemispheric connections between the left anterior temporal/inferior frontal cortex and the central cortex. Lagged phase synchronization values of the connections showing significant between-group difference (p<0.05 corrected) in alpha and theta bands are given in Table 3.
