Preferential encoding of movement amplitude and speed in the primary motor cortex and cerebellum

Abstract

Voluntary movements require control of multiple kinematic parameters, a task carried out by a distributed brain architecture. However, it remains unclear whether regions along the motor system encode single, or rather a mixture of, kinematic parameters during action execution. Here, rapid event-related functional magnetic resonance imaging was used to differentiate brain activity along the motor system during the encoding of movement amplitude, duration, and speed. We present cumulative evidence supporting preferential encoding of kinematic parameters along the motor system, based on blood-oxygenation-level dependent signal recorded in a well-controlled single-joint wrist-flexion task. Whereas activity in the left primary motor cortex (M1) showed preferential encoding of movement amplitude, the anterior lobe of the right cerebellum (primarily lobule V) showed preferential encoding of movement speed. Conversely, activity in the left supplementary motor area (SMA), basal ganglia (putamen), and anterior intraparietal sulcus was not preferentially modulated by any specific parameter. We found no preference in peak activation for duration encoding in any of the tested regions. Electromyographic data was mainly modulated by movement amplitude, restricting the distinction between amplitude and muscle force encoding. Together, these results suggest that during single-joint movements, distinct kinematic parameters are controlled by largely distinct brain-regions that work together to produce and control precise movements. Hum Brain Mapp 38:5970-5986, 2017. © 2017 Wiley Periodicals, Inc.

Brain Motor Network Changes in Parkinson's Disease: Evidence from Meta‐Analytic Modeling

“…This has been demonstrated for the posterior putamen, [69][70][71][72] SMA, 70,73 M1, 72,[74][75][76][77] and the cerebellum. 71,72,[77][78][79] Furthermore, it should be noted that this meta-analysis was conducted in studies using a variety of motor tasks implying that any detected difference should not be specific to a certain kind of movement, but rather a general process underlying motor execution. We speculate that the process that is probed in many of these neuroimaging studies in PD might be the modulation of movement vigor, which is a crucial aspect of motor control, 80 and reduced movement vigor constitutes a core motor impairment in PD (clinically termed bradykinesia).…”

“…Although reverse inference should be taken with caution, 68 there is strong evidence from neuroimaging and electrophysiological studies for a critical role of this network in the modulation of movement vigor. This has been demonstrated for the posterior putamen, 69‐72 SMA, 70,73 M1, 72,74‐77 and the cerebellum 71,72,77‐79 . Furthermore, it should be noted that this meta‐analysis was conducted in studies using a variety of motor tasks implying that any detected difference should not be specific to a certain kind of movement, but rather a general process underlying motor execution.…”

Brain activity associated with quadriceps strength deficits after anterior cruciate ligament reconstruction

“…Voluntary muscle contraction requires distributed activity among several brain structures to encode movement related parameters. For example, neurons within the sensorimotor cortex regulate movement amplitude 40 and direction 41 . Cramer et al 42 demonstrated that neuronal activity within the motor cortex and surrounding regions exhibit a proportional response to force output in healthy adults (more force output equated with more neural activity).…”