The results of the native space method showed a single pair of regions (Phi, SM) whose functional connectivity significantly increased with age in both hemispheres. After interhemispheric averaging, however, this age-dependent change in functional connectivity was not found. A more important
consequence was that the highly significant age-related difference in connectivity between supramarginal and superior-frontal regions, which was detected only in the right hemisphere prior to averaging, was lost by averaging the signals. selleck correlation with cognition Using linear regression models, we examined the relationship between functional connectivity and cognition across the seven regional pairs that were found Inhibitors,research,lifescience,medical to be altered significantly by age. These analyses were performed separately in the young and elder groups. Connectivity in only one of the seven region pairs with significant age-related DMN functional connectivity
disruption (supramarginal and superior-frontal on the right hemisphere) was correlated Inhibitors,research,lifescience,medical with cognitive performance; connectivity in the remaining six significant findings was not found to be related to any Inhibitors,research,lifescience,medical of the cognitive domains’ factor scores in the young or old subject groups. It is interesting to note that the age-related disruption in functional connectivity between SM and SF in the right hemisphere was also the only finding that survived Bonferroni correction (P < 0.00056). In the elder participants, the magnitude Inhibitors,research,lifescience,medical of functional connectivity of the SM and SF in the right hemisphere was correlated
with better memory (P = 0.050) and general fluid ability (P = 0.013), but not with speed of processing (P = 0.182) or vocabulary (P = 0.192). In young participants, the magnitude of functional connectivity between SM and SF regions in right hemisphere was related to better speed of processing (P = 0.008), but not to memory (P = 0.274), general fluid ability (P = 0.173), or vocabulary (P = 0.772). Functional connectivity Inhibitors,research,lifescience,medical between the same regions in the left hemisphere was not related to cognition in either age group. Results of the correlation between SM and SF functional connectivity and cognitive performance are summarized in Figure 9. We excluded vocabulary for this figure as we did not find it to be correlated with much any of our significant connectivity findings. Figure 9 Relationship between right and left hemisphere functional connectivity between supramarginal gyrus and superior-frontal cortex on the right (A–C) and left (D–F) hemisphere and cognitive domains’ factor scores: memory (A and D), speed of … Discussion In this study, we explored age-related disruption in the functional connectivity among 10 neuroanatomical regions consistently reported as part of the DMN (Buckner et al. 2008; Raichle 2011; Seibert and Brewer 2011).