Relevant conflicts of interest/financial disclosures: Nothing to report.
Imaging: What can it tell us about parkinsonian gait?
Article first published online: 16 OCT 2013
© 2013 Movement Disorder Society
Special Issue: Gait and Balance in Movement Disorders
Volume 28, Issue 11, pages 1492–1500, 15 September 2013
How to Cite
Bohnen, N. I. and Jahn, K. (2013), Imaging: What can it tell us about parkinsonian gait?. Mov. Disord., 28: 1492–1500. doi: 10.1002/mds.25534
Full financial disclosures and author roles may be found in the online version of this article.
- Issue published online: 16 OCT 2013
- Article first published online: 16 OCT 2013
- Manuscript Accepted: 29 APR 2013
- Manuscript Revised: 8 APR 2013
- Manuscript Received: 5 MAR 2013
- Parkinson's disease;
- pedunculopontine nucleus;
- progressive supranuclear palsy
Functional neuroimaging has provided new tools to study cerebral gait control in Parkinson's disease (PD). First, imaging of blood flow functions has identified a supraspinal locomotor network that includes the (frontal) cortex, basal ganglia, brainstem tegmentum, and cerebellum. These studies also emphasize the cognitive and attentional dependency of gait in PD. Furthermore, gait in PD and related syndromes like progressive supranuclear palsy may be associated with dysfunction of the indirect, modulatory prefrontal–subthalamic–pedunculopontine loop of locomotor control. The direct, stereotyped locomotor loop from the primary motor cortex to the spinal cord with rhythmic cerebellar input appears to be preserved and may contribute to the unflexible gait pattern in parkinsonian gait. Second, neurotransmitter and proteinopathy imaging studies are beginning to unravel novel mechanisms of parkinsonian gait and postural disturbances. Dopamine displacement imaging studies have shown evidence for a mesofrontal dopaminergic shift from a depleted striatum in parkinsonian gait. This may place additional burden on other brain systems mediating attention functions to perform previously automatic motor tasks. For example, our preliminary cholinergic imaging studies suggest significant slowing of gait speed when additional forebrain cholinergic denervation occurs in PD. Cholinergic denervation of the pedunculopontine nucleus and its thalamic projections have been associated with falls and impaired postural control. Deposition of β-amyloid may represent another non-dopaminergic correlate of gait disturbance in PD. These findings illustrate the emergence of dopamine non-responsive gait problems to reflect the transition from a predominantly hypodopaminergic disorder to a multisystem neurodegenerative disorder involving non-dopaminergic locomotor network structures and pathologies. © 2013 International Parkinson and Movement Disorder Society