Basal ganglia hypoactivity during grip force in drug naïve Parkinson's disease

Abstract

The basal ganglia (BG) are impaired in Parkinson's disease (PD), but it remains unclear which nuclei are impaired during the performance of motor tasks in early-stage PD. Therefore, this study was conducted to determine which nuclei function abnormally, and whether cortical structures are also affected by early-stage PD. The study also determined if cerebellar hyperactivity is found early in the course of PD. Blood oxygenation level dependent activation was compared between 14 early-stage drug-naïve PD patients and 14 controls performing two precision grip force tasks using functional magnetic resonance imaging at 3 T. The grip tasks used in this study were chosen because both tasks are known to provide robust activation in BG nuclei, and the two tasks were similar except that the 2-s task required more switching between contraction and relaxation than the 4-s task. The 4-s task revealed that PD patients were hypoactive relative to controls only in putamen and external globus pallidus, and thalamus. In the 2-s task, PD patients were hypoactive throughout all BG nuclei, thalamus, M1, and supplementary motor area. There were no differences in cerebellar activation between groups during either task. Regions of interest analysis revealed that the hypoactivity observed in PD patients during the 2-s task became more pronounced over time as patients performed the task. This suggests that a motor task that requires switching can accentuate abnormal activity throughout all BG nuclei of early-stage, drug-naive PD, and that the abnormal activity becomes more pronounced with repeated task performance in these patients.

Global signal regression has complex effects on regional homogeneity of resting state fMRI signal

“…Previous studies indicated these regions involved in motor control [45][46][47][48][49] and motor learning [50,51]. Therefore, here the role of the two regions may be involved with regulating the ongoing activity of motor cortex between EO and EC (Fig.…”

The NINDS Parkinson's disease biomarkers program

“…The focus is on motor task-based functional MRI using a reliable motor task, and diffusion MRI using novel analytic methods (10, 11). The goal is to develop unique candidate markers of progression in PD (in comparison to other movement disorders).…”

Sensory and motor cortex function contributes to symptom severity in spinocerebellar ataxia type 6

“…1a) because previous studies have shown reliable blood oxygen level-dependent (BOLD) activity changes in individuals with neurological disorders that include Parkinson’s disease, essential tremor, multiple system atrophy, and progressive supranuclear palsy (Burciu et al 2015; Neely et al 2015; Planetta et al 2015a; Spraker et al 2010). Further, our pilot data confirmed that SCA6 patients were able to execute pinch grip force with similar behavioral performance as age-matched healthy controls.…”

“…Using a grip force control fMRI paradigm (Neely et al 2015; Planetta et al 2015a; Spraker et al 2010), we explored task-based fMRI activity within sensory and motor cortex and cerebellum, and task-based functional connectivity between cortical motor regions (i.e., sensorimotor cortex and supplementary motor area: SMA) and cerebellum. In addition, free-water diffusion magnetic resonance imaging (dMRI) was assessed using a bi-tensor model to evaluate the tissue compartment and the free-water compartment within cerebellar regions (i.e., dentate, cerebellar lobules V and VI, cerebellar vermis, and peduncles).…”