101. Resting state functional connectivity of the human habenula using ultra-high field, high-resolution imaging at 7T
- Author
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Bottenhorn, Katherine L., Robinson, Jennifer L., Yanes, Julio A., Flannery, Jessica S., Sutherland, Matthew T., and Laird, Angela R.
- Subjects
functional connectivity ,human neuroscience - Abstract
The habenula is a small region immediately posterior to the medial thalamus and dorsal to the posterior commissure. This region, implicated in reward processing, receives input from several subcortical regions via the stria medullaris and projects to midbrain regions, modulating serotonin and dopamine release. In order to more broadly investigate the interactions between the habenula and the rest of the brain, we used a seed-to-voxel analysis to probe the intrinsic connectivity of the habenula. Data were collected from 22 healthy, individuals on a 7-Tesla Siemens MAGNETOM scanner housed at Auburn University’s MRI Research Center. We acquired structural and resting-state functional images with sub-millimeter resolution. The habenula was manually defined in each subject’s native space and these ROIs were then used as seed regions from which we extracted the mean BOLD signal time-course and used FSL’s FEAT to assess correlations between time-courses voxels in the rest of the brain with that time-course. Higher-level analysis was performed using FSL’s linear analysis of mixed effects. Our seed-based analysis uncovered temporal correlations (Pcorrected < 0.0001) of the habenula’s BOLD signal with regions known to be structurally connected, including the caudate and putamen (CPu), internal globus pallidus (GPi), the nucleus accumbens (NAcc), and substantia nigra (SN). Connectivity was demonstrated between the habenula and multiple midline regions, as well, including portions of the anterior, mid- and posterior cingulate cortex (ACC, MCC, and PCC), ventromedial prefrontal cortex (vmPFC), thalamus, and cerebellar vermis. The cingulate clusters appear to extend into the paracingulate sulcus, supplementary motor area (SMA), and pre-SMA, as well. The correlation between habenula and ACC activity at rest suggests an integration of conflict monitoring into habenula’s negative feedback and reward prediction errors processing. Furthermore, habenular connectivity with nodes of the cortico-basal motor loop (CPu, GPi, SN, SMA, pre-SMA) supports the notion that the habenula is involved translation of negative feedback to goal-directed action (or the inhibition thereof). This, combined with implied connections to default mode network (DMN) hubs, PCC and vmPFC, indicates that the habenula might be playing a vital role in integrating the associations between actions and negative consequences into the mental rehearsal component of mind-wandering.
- Published
- 2016
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