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bioRxiv · 10.1101/571513

Resting-state functional connectivity modulates the BOLD activation induced by nucleus accumbens stimulation in the swine brain

Abstract

While it is known that the clinical efficacy of deep brain stimulation (DBS) alleviates motor-related symptoms, cognitive and behavioral effects of DBS and its action mechanism on brain circuits are not clearly understood. By combining functional magnetic resonance imaging (fMRI) and DBS, we investigated the pattern of blood-oxygenation-level-dependent (BOLD) signal changes induced by stimulating the nucleus accumbens and how inter-regional resting-state functional connectivity is related with the stimulation DBS effect in a healthy swine model. We found that the pattern of stimulation-induced BOLD activation was diffused across multiple functional networks including the prefrontal, limbic, and thalamic regions, altering inter-regional functional connectivity after stimulation. Furthermore, our results showed that the strength of the DBS effect is closely related to the strength of inter-regional resting-state functional connectivity including stimulation locus and remote brain regions. Our results reveal the impact of nucleus accumbens stimulation on major functional networks, highlighting functional connectivity may mediate the modulation effect of DBS via large-scale brain networks.

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Cho, S., Hachmann, J. T., Balzekas, I., In, M.-H., Andres-Beck, L. G., Lee, K. H., Min, H.-K., Jo, H. J.. 2019-03-09. Resting-state functional connectivity modulates the BOLD activation induced by nucleus accumbens stimulation in the swine brain. https://doi.org/10.1101/571513

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