Rapid and specific gray matter changes in M1 induced by balance training

Area of Science:

• Neuroscience
• Neuroimaging
• Motor Control

Background:

• Cortical plasticity, the brain's ability to change its structure and function, is crucial for motor learning.
• Previous studies in humans showed macroscopic structural brain changes after weeks or months of training, while animal studies indicated faster microstructural changes.

Purpose of the Study:

• To investigate immediate and specific training-induced alterations in human motor cortical gray matter using magnetic resonance imaging (MRI).
• To test if short-term motor practice leads to detectable changes in cortical thickness.

Main Methods:

• Participants underwent magnetic resonance imaging (MRI) before and after a one-hour complex balancing task.
• Cortical thickness was measured in specific motor cortical regions, focusing on effector representations involved in balance control (lower limb and trunk).
• Cerebral blood flow was assessed to rule out its influence on observed changes.

Main Results:

• Localized increases in motor cortical thickness were observed after only one hour of balancing practice.
• These structural changes were specific to the motor cortical areas responsible for lower limb and trunk control during the task.
• The observed cortical thickness changes increased linearly with training duration and were independent of changes in resting cerebral blood flow.

Conclusions:

• Motor learning can induce rapid and specific gray matter changes in the primary motor cortex (M1) in humans.
• These findings challenge the notion that significant structural brain changes require prolonged training periods.
• The study highlights the remarkable plasticity of the motor cortex in response to new skill acquisition.