@article {Li1097, author = {Li, Wenjun and Douglas Ward, B and Liu, Xiaolin and Chen, Gang and Jones, Jennifer L and Antuono, Piero G and Li, Shi-Jiang and Goveas, Joseph S}, title = {Disrupted small world topology and modular organisation of functional networks in late-life depression with and without amnestic mild cognitive impairment}, volume = {86}, number = {10}, pages = {1097--1105}, year = {2015}, doi = {10.1136/jnnp-2014-309180}, publisher = {BMJ Publishing Group Ltd}, abstract = {Background The topological architecture of the whole-brain functional networks in those with and without late-life depression (LLD) and amnestic mild cognitive impairment (aMCI) are unknown.Aims To investigate the differences in the small-world measures and the modular community structure of the functional networks between patients with LLD and aMCI when occurring alone or in combination and cognitively healthy non-depressed controls.Methods 79 elderly participants (LLD (n=23), aMCI (n=18), comorbid LLD and aMCI (n=13), and controls (n=25)) completed neuropsychiatric assessments. Graph theoretical methods were employed on resting-state functional connectivity MRI data.Results LLD and aMCI comorbidity was associated with the greatest disruptions in functional integration measures (decreased global efficiency and increased path length); both LLD groups showed abnormal functional segregation (reduced local efficiency). The modular network organisation was most variable in the comorbid group, followed by patients with LLD-only. Decreased mean global, local and nodal efficiency metrics were associated with greater depressive symptom severity but not memory performance.Conclusions Considering the whole brain as a complex network may provide unique insights on the neurobiological underpinnings of LLD with and without cognitive impairment.}, issn = {0022-3050}, URL = {https://jnnp.bmj.com/content/86/10/1097}, eprint = {https://jnnp.bmj.com/content/86/10/1097.full.pdf}, journal = {Journal of Neurology, Neurosurgery \& Psychiatry} }