Visuospatial cognition in people with Parkinson's disease: a pilot study assessing a block span task using fMRI

Area of Science:

• Neuroscience
• Cognitive Science
• Neurology

Background:

• Parkinson's Disease (PD) often impairs visuospatial working memory (WM), affecting patients' quality of life.
• Understanding the neurophysiological basis of these impairments is crucial for developing effective interventions.
• The Block Span Task (BST) is a novel tool adapted for functional MRI (fMRI) to study visuospatial WM in PD.

Purpose of the Study:

• To evaluate the feasibility of the BST as an in-scanner visuospatial WM task for older adults with mild to moderate PD.
• To examine the neurophysiological mechanisms underlying visuospatial impairment in PD using fMRI.
• To determine if the BST can be practically administered to PD patients within an MRI environment.

Main Methods:

• Recruited 21 older adults with mild-moderate PD (mean age 70 ± 8 years).
• Participants underwent the BST task in an MRI scanner after abstaining from medication.
• Functional MRI data were analyzed using independent component analysis to identify engaged neural networks.

Main Results:

• The BST task was successfully administered to PD patients, demonstrating feasibility.
• The encoding phase of the BST engaged relevant neural networks, including the superior temporal gyrus, superior medial frontal gyrus, precuneus, and posterior cingulate cortex.
• These networks involved auditory, cognitive, and default-mode networks, consistent with visuospatial WM processing.

Conclusions:

• The BST is a feasible fMRI task for assessing visuospatial WM in patients with Parkinson's Disease.
• The task engages significant neural regions, providing preliminary evidence for its utility in studying PD-related cognitive alterations.
• Further research is needed to refine the BST and explore functional network differences compared to healthy individuals.