Kuramoto model simulation of neural hubs and dynamic synchrony in the human cerebral connectome.
BACKGROUND
The topological structure of the wiring of the mammalian brain cortex plays an important role in shaping the functional dynamics of large-scale neural activity. Due to their central embedding in the network, high degree hub regions and their connections (often referred to as the 'rich club') have been hypothesized to facilitate intermodular neural communication and global integration of information by means of synchronization. Here, we examined the theoretical role of anatomical hubs and their wiring in brain dynamics. The Kuramoto model was used to simulate interaction of cortical brain areas by means of coupled phase oscillators-with anatomical connections between regions derived from diffusion weighted imaging and module assignment of brain regions based on empirically determined resting-state data.


RESULTS
Our findings show that synchrony among hub nodes was higher than any module's intramodular synchrony (p < 10(-4), for cortical coupling strengths, λ, in the range 0.02 < λ < 0.05), suggesting that hub nodes lead the functional modules in the process of synchronization. Furthermore, suppressing structural connectivity among hub nodes resulted in an elevated modular state (p < 4.1 × l0(-3), 0.015 < λ < 0.04), indicating that hub-to-hub connections are critical in intermodular synchronization. Finally, perturbing the oscillatory behavior of hub nodes prevented functional modules from synchronizing, implying that synchronization of functional modules is dependent on the hub nodes' behavior.


CONCLUSIONS
Our results converge on anatomical hubs having a leading role in intermodular synchronization and integration in the human brain.
Department of Neurology, Brain Center Rudolf Magnus, University Medical Center Utrecht, Heidelberglaan 100, PO Box 85500, 3508 GA, Utrecht, Netherlands. r.schmidt@umcutrecht.nl.
Ruben
R
Schmidt
Department of Neurology, Brain Center Rudolf Magnus, University Medical Center Utrecht, Heidelberglaan 100, PO Box 85500, 3508 GA, Utrecht, Netherlands. lafl0047@umn.edu.
Karl J R
KJ
LaFleur
Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, Heidelberglaan 100, PO Box 85500, 3508 GA, Utrecht, Netherlands. m.a.dereus-4@umcutrecht.nl.
Marcel A
MA
de Reus
Department of Neurology, Brain Center Rudolf Magnus, University Medical Center Utrecht, Heidelberglaan 100, PO Box 85500, 3508 GA, Utrecht, Netherlands. l.h.vandenberg@umcutrecht.nl.
Leonard H
LH
van den Berg
Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, Heidelberglaan 100, PO Box 85500, 3508 GA, Utrecht, Netherlands. m.p.vandenheuvel@umcutrecht.nl.
Martijn P
MP
van den Heuvel
D000328:Adult; D000818:Animals; D001921:Brain / Q000033:anatomy & histology / Q000502:physiology*; D015331:Cohort Studies; D003198:Computer Simulation; D063132:Connectome; D003344:Cortical Synchronization / Q000502:physiology*; D016208:Databases, Factual; D005260:Female; D006801:Humans; D008251:Macaca; D008279:Magnetic Resonance Imaging; D008297:Male; D008959:Models, Neurological; D009434:Neural Pathways / Q000033:anatomy & histology / Q000502:physiology; D056347:Neuroanatomical Tract-Tracing Techniques; D012146:Rest