MRI-compatible device for examining brain activation related to stepping

Area of Science:

• Neuroscience
• Motor Control
• Biomechanics

Background:

• Repetitive and alternating lower limb movements are fundamental to human gait.
• Previous functional magnetic resonance imaging (fMRI) studies faced technical challenges in investigating neural mechanisms of gait.
• Understanding the neural basis of gait control is crucial for rehabilitation and neurological disorder research.

Purpose of the Study:

• To investigate the neural mechanisms underlying repetitive and alternating lower limb movements using fMRI.
• To present a novel treadmill device enabling gait studies within an MRI scanner.
• To correlate kinematic features of lower limb movement with brain activation patterns.

Main Methods:

• Developed a novel treadmill device compatible with functional magnetic resonance imaging (fMRI).
• 19 healthy subjects performed repetitive and alternating lower limb movements guided by visual cues inside the MRI scanner.
• Quantified kinematic features (amplitude, frequency) of lower limb displacements during stepping.

Main Results:

• Significant bilateral blood oxygen level dependent (BOLD) signal increases were observed in sensorimotor cortex, supplementary motor area, premotor cortex, prefrontal cortex, parietal lobules, putamen, and cerebellum.
• These activated regions are known to be involved in lower limb motor control.
• A right-lateralized network including striatal, extrastriatal, and fronto-parietal areas showed activation related to individual motor adjustments.

Conclusions:

• The novel treadmill device successfully enabled the study of gait-related brain activation using fMRI.
• The findings identify a distributed neural network supporting repetitive and alternating lower limb movements.
• Individual motor adjustments during gait involve a distinct right-lateralized fronto-striatal-parietal network.