Increased functional connectivity of thalamic subdivisions in patients with Parkinson's disease

PLoS One. 2019 Sep 4;14(9):e0222002. doi: 10.1371/journal.pone.0222002. eCollection 2019.

Abstract

Parkinson's disease (PD) affects 2-3% of the population over the age of 65 with loss of dopaminergic neurons in the substantia nigra impacting the functioning of basal ganglia-thalamocortical circuits. The precise role played by the thalamus is unknown, despite its critical role in the functioning of the cerebral cortex, and the abnormal neuronal activity of the structure in PD. Our objective was to more clearly elucidate how functional connectivity and morphology of the thalamus are impacted in PD (n = 32) compared to Controls (n = 20). To investigate functional connectivity of the thalamus we subdivided the structure into two important regions-of-interest, the first with putative connections to the motor cortices and the second with putative connections to prefrontal cortices. We then investigated potential differences in the size and shape of the thalamus in PD, and how morphology and functional connectivity relate to clinical variables. Our data demonstrate that PD is associated with increases in functional connectivity between motor subdivisions of the thalamus and the supplementary motor area, and between prefrontal thalamic subdivisions and nuclei of the basal ganglia, anterior and dorsolateral prefrontal cortices, as well as the anterior and paracingulate gyri. These results suggest that PD is associated with increased functional connectivity of subdivisions of the thalamus which may be indicative alterations to basal ganglia-thalamocortical circuitry.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Female
  • Humans
  • Magnetic Resonance Imaging
  • Male
  • Motor Cortex / diagnostic imaging
  • Motor Cortex / physiopathology
  • Neural Pathways / diagnostic imaging
  • Neural Pathways / physiopathology*
  • Parkinson Disease / diagnostic imaging
  • Parkinson Disease / physiopathology*
  • Prefrontal Cortex / diagnostic imaging
  • Prefrontal Cortex / physiopathology
  • Thalamus / diagnostic imaging
  • Thalamus / physiopathology*

Grants and funding

CO-W would like to acknowledge the Australian National University for their funding support via the University Research Scholarship. Work in DvW and OH’s laboratory was supported by the European Research Council, the Swedish Research Council, the Strategic Research Area MultiPark (Multidisciplinary Research in Parkinson’s disease) at Lund University, the Swedish Brain Foundation, the Parkinson Foundation of Sweden, the Skåne University Hospital Foundation and the Swedish federal government under the ALF agreement. Funding sources had no role in the conduct of this study, its analysis, interpretation of the data or in the preparation, review or approval of the manuscript.