2 research outputs found
Resting-State Functional Connectivity in Late-Life Depression: Higher Global Connectivity and More Long Distance Connections
Functional magnetic resonance imaging recordings in the resting-state (RS)
from the human brain are characterized by spontaneous low-frequency
fluctuations in the blood oxygenation level dependent signal that reveal
functional connectivity (FC) via their spatial synchronicity. This RS study
applied network analysis to compare FC between late-life depression (LLD)
patients and control subjects. Raw cross-correlation matrices (CM) for LLD were
characterized by higher FC. We analyzed the small-world (SW) and modular
organization of these networks consisting of 110 nodes each as well as the
connectivity patterns of individual nodes of the basal ganglia. Topological
network measures showed no significant differences between groups. The
composition of top hubs was similar between LLD and control subjects, however
in the LLD group posterior medial-parietal regions were more highly connected
compared to controls. In LLD, a number of brain regions showed connections with
more distant neighbors leading to an increase of the average Euclidean distance
between connected regions compared to controls. In addition, right caudate
nucleus connectivity was more diffuse in LLD. In summary, LLD was associated
with overall increased FC strength and changes in the average distance between
connected nodes, but did not lead to global changes in SW or modular
organization