Neural Correlates of Knee Extension and Flexion Force Control: A Kinetically-Instrumented Neuroimaging Study

Abstract

Background: The regulation of muscle force is a vital aspect of sensorimotor control, requiring intricate neural processes. While neural activity associated with upper extremity force control has been documented, extrapolation to lower extremity force control is limited. Knowledge of how the brain regulates force control for knee extension and flexion may provide insights as to how pathology or intervention impacts central control of movement.Objectives: To develop and implement a neuroimaging-compatible force control paradigm for knee extension and flexion.Methods: A magnetic resonance imaging (MRI) safe load cell was used in a customized apparatus to quantify force (N) during neuroimaging (Philips Achieva 3T). Visual biofeedback and a target sinusoidal wave that fluctuated between 0 and 5 N was provided via an MRI-safe virtual reality display. Fifteen right leg dominant female participants (age = 20.3 ± 1.2 years, height = 1.6 ± 0.10 m, weight = 64.8 ± 6.4 kg) completed a knee extension and flexion force matching paradigm during neuroimaging. The force-matching error was calculated based on the difference between the visual target and actual performance. Brain activation patterns were calculated and associated with force-matching error and the difference between quadriceps and hamstring force-matching tasks were evaluated with a mixed-effects model (z > 3.1, p < 0.05, cluster corrected).Results: Knee extension and flexion force-matching tasks increased BOLD signal among cerebellar, sensorimotor, and visual-processing regions. Increased knee extension force-matching error was associated with greater right frontal cortex and left parietal cortex activity and reduced left lingual gyrus activity. Increased knee flexion force-matching error was associated with reduced left frontal and right parietal region activity. Knee flexion force control increased bilateral premotor, secondary somatosensory, and right anterior temporal activity relative to knee extension. The force-matching error was not statistically different between tasks.Conclusion: Lower extremity force control results in unique activation strategies depending on if engaging knee extension or flexion, with knee flexion requiring increased neural activity (BOLD signal) for the same level of force and no difference in relative error. These fMRI compatible force control paradigms allow precise behavioral quantification of motor performance concurrent with brain activity for lower extremity sensorimotor function and may serve as a method for future research to investigate how pathologies affect lower extremity neuromuscular function.

Brain Response To A Knee Proprioception Task Among Persons With Anterior Cruciate Ligament Reconstruction And Controls

“…The importance of the insula to position sense is further supported by ndings previously mentioned here for the upper limbs following stroke, whereby lesions in this region were associated with greater errors when attempting to actively move the unaffected arm to the mirrormatched position of the passively moved contralateral arm 39 . Associated response for the right supramarginal gyrus is supported by previous ndings of greater response during a proprioceptive task of force matching at the knee among asymptomatic females 32 .…”

“…Our knee JPS test evoked response in the ipsilateral precentral gyrus for the right test side and cingulate gyri for both test sides. Response in these regions has also been observed among asymptomatic individuals during active knee exion tasks of JPS 13 and force matching 32 . Response in the right middle frontal gyrus was seen for both test sides and has been previously associated with switching between exogenous and endogenous attention 33 , relevant for our JPS task where the focus of attention changes from external instructions on a screen to internal sensations related to proprioception.…”

Brain Response to a Knee Proprioception Task Among Persons With Anterior Cruciate Ligament Reconstruction and Controls

“…Our knee JPS test evoked response in the ipsilateral precentral gyrus for the right test side and cingulate gyri for both test sides. Response in these regions has also been observed among asymptomatic individuals during active knee flexion tasks of JPS ( Callaghan et al, 2012 ) and force matching ( Grooms et al, 2021 ). Response in the right middle frontal gyrus was seen for both test sides and has been previously associated with switching between external and internal focus of attention ( Japee et al, 2015 ), relevant for our JPS task where the focus of attention changes from external instructions on a screen to internal sensations related to proprioception.…”

The Effects of Visuomotor Training on the Functional Recovery of Post-Surgery Musculoskeletal Conditions: A Randomized Controlled Trial

“…Information processing between the basal ganglia, cerebellum, and brainstem may enable automatic regulation of muscle tone and rhythmic limb movements in the absence of conscious awareness [34]. When a locomoting subject experiences a musculoskeletal disorder in the lower limbs, they somewhat alter this sensory-motor processing and develop individual compensation strategies to avoid pain during walking [35]. In particular, in the case of subjects undergoing joint replacement for osteoarthritis, these strategies are expressed in gait patterns characterized by clearly evasive movements, which are so highly automated that they still endure post-surgery [36].…”