The functional role of conscious sensation of movement.

This paper proposes a new framework for investigating neural signals sufficient for a conscious sensation of movement and their role in motor control. We focus on signals sufficient for proprioceptive awareness, particularly from muscle spindle activation and from primary motor cortex (M1). Our review of muscle vibration studies reveals that afferent signals alone can induce conscious sensations of movement.

Distinct mechanisms for online and offline motor skill learning across human development.

The human central nervous system (CNS) undergoes tremendous changes from childhood to adulthood and this may affect how individuals at different stages of development learn new skills. Here, we studied motor skill learning in children, adolescents, and young adults to test the prediction that differences in the maturation of different learning mechanisms lead to distinct temporal patterns of motor learning during practice and overnight. We found that overall learning did not differ between children, adolescents, and young adults.

Mind over body: Interfering with the inner voice is detrimental to endurance performance.

In two preregistered experiments, we investigated whether covert language is involved in sustained physical efforts, specifically if people are less able to push themselves physically when distracted from using inner speech. In both experiments, participants performed 12 cycling trials (Experiment 1: N = 49; Experiment 2: N = 50), each lasting 1 min where participants were required to cycle as fast as possible while simultaneously engaging in either a visuospatial task, a verbal task or no interference. Experiment 1: Participants performed worse in the verbal interference condition compared with the control condition (d = 0.

Moving without sensory feedback: online TMS over the dorsal premotor cortex impairs motor performance during ischemic nerve block.

The study investigates the role of dorsal premotor cortex (PMd) in generating predicted sensory consequences of movements, i.e. corollary discharges.

Cortical signatures of precision grip force control in children, adolescents, and adults.

Human dexterous motor control improves from childhood to adulthood, but little is known about the changes in cortico-cortical communication that support such ontogenetic refinement of motor skills. To investigate age-related differences in connectivity between cortical regions involved in dexterous control, we analyzed electroencephalographic data from 88 individuals (range 8-30 years) performing a visually guided precision grip task using dynamic causal modelling and parametric empirical Bayes. Our results demonstrate that bidirectional coupling in a canonical 'grasping network' is associated with precision grip performance across age groups.

Valence, form, and content of self-talk predict sport type and level of performance.

In this paper, we aimed to test whether we could predict sport type (badminton or running) and marathon proficiency from the valence, form, and content of the athletes' self-reported inner speech. Additionally, we wanted to assess the difference between self-talk during high intensity and low intensity exercise. The present study corroborated existing research - we were able to predict both sport type in Study 1 and intensity level as well as marathon proficiency in Study 2 from questionnaire data using machine learning models.

Measures of agency.

The sense of agency is typically defined as the experience of controlling one's own actions, and through them, changes in the external environment. It is often assumed that this experience is a single, unified construct that can be experimentally manipulated and measured in a variety of ways. In this article, we challenge this assumption.

Directed connectivity between primary and premotor areas underlying ankle force control in young and older adults.

The control of ankle muscle force is an integral component of walking and postural control. Aging impairs the ability to produce force steadily and accurately, which can compromise functional capacity and quality of life. Here, we hypothesized that reduced force control in older adults would be associated with altered cortico-cortical communication within a network comprising the primary motor area (M1), the premotor cortex (PMC), parietal, and prefrontal regions.

Spastic movement disorder: should we forget hyperexcitable stretch reflexes and start talking about inappropriate prediction of sensory consequences of movement?

Spastic movement disorder is characterized by reduced ability to selectively activate muscles with significant co-activation of antagonist muscles. It has traditionally been thought that hyperexcitable stretch reflexes have a central role in the pathophysiology and the clinical manifestations of the disorder. Here we argue that the main functional challenges for persons with spastic movement disorder are related to contractures, paresis, weak muscles and inappropriate central motor commands, whereas hyperexcitable reflexes play no or only an insignificant functional role.

Are sensorimotor experiences the key for successful early intervention in infants with congenital brain lesion?

Living with a congenital brain lesion may have detrimental effects on the ability to do everyday activities, but contrary to acquired brain lesions, people and in particular children, with congenital brain lesions may have limited or no experience of how their bodies work. This absence of experience gives rise to challenges for habilitation of sensorimotor abilities and derived cognitive abilities. How can motor and cognitive abilities be achieved and trained in an individual with no experience of potential abilities? In this article, we aim to review the existing knowledge about the development of sensorimotor integration.

Sense of agency for movements.

In this paper, we argue that the comparator model is not a satisfactory model of sense of agency (SoA). We present a theoretical argument and experimental studies. We show (1) most studies of SoA neglect a distinction between SoA associated with movements (narrow SoA) and SoA associated with environmental events (broad SoA); (2) the comparator model emerges from experimental studies of sensory consequences narrowly associated with movements; (3) narrow SoA can be explained by a comparator model, but a motor signal model is simpler and explain narrow SoA equally well; and (4) standard experimental paradigms study only broad SoA.

Modulation of task-related cortical connectivity in the acute and subacute phase after stroke.

The functional relevance of cortical reorganization post-stroke is still not well understood. In this study, we investigated task-specific modulation of cortical connectivity between neural oscillations in key motor regions during the early phase after stroke. EEG and EMG recordings were examined from 15 patients and 18 controls during a precision grip task using the affected hand.

Corticomuscular coherence in the acute and subacute phase after stroke.

Objective: Stroke is one of the leading causes of physical disability due to damage of the motor cortex or the corticospinal tract. In the present study we set out to investigate the role of adaptations in the corticospinal pathway for motor recovery during the subacute phase after stroke.

Methods: We examined 19 patients with clinically diagnosed stroke and 18 controls.

Modulation of fronto-parietal connections during the rubber hand illusion.

Accumulating evidence suggests that parieto-frontal connections play a role in adjusting body ownership during the Rubber Hand Illusion (RHI). Using a motor version of the rubber hand illusion paradigm, we applied single-site and dual-site transcranial magnetic stimulation (TMS) to investigate cortico-spinal and parietal-frontal connectivity during perceived rubber hand ownership. Healthy volunteers received a conditioning TMS pulse over left anterior intraparietal sulcus (aIPS) and a test TMS pulse over left primary motor cortex (M1).

Tuning the Brake While Raising the Stake: Network Dynamics during Sequential Decision-Making.

Unlabelled: When gathering valued goods, risk and reward are often coupled and escalate over time, for instance, during foraging, trading, or gambling. This escalating frame requires agents to continuously balance expectations of reward against those of risk. To address how the human brain dynamically computes these tradeoffs, we performed whole-brain fMRI while healthy young individuals engaged in a sequential gambling task.

Changes in corticospinal drive to spinal motoneurones following tablet-based practice of manual dexterity.

The use of touch screens, which require a high level of manual dexterity, has exploded since the development of smartphone and tablet technology. Manual dexterity relies on effective corticospinal control of finger muscles, and we therefore hypothesized that corticospinal drive to finger muscles can be optimized by tablet-based motor practice. To investigate this, sixteen able-bodied females practiced a tablet-based game (3 × 10 min) with their nondominant hand requiring incrementally fast and precise pinching movements involving the thumb and index fingers.

Abnormal dopaminergic modulation of striato-cortical networks underlies levodopa-induced dyskinesias in humans.

Dopaminergic signalling in the striatum contributes to reinforcement of actions and motivational enhancement of motor vigour. Parkinson's disease leads to progressive dopaminergic denervation of the striatum, impairing the function of cortico-basal ganglia networks. While levodopa therapy alleviates basal ganglia dysfunction in Parkinson's disease, it often elicits involuntary movements, referred to as levodopa-induced peak-of-dose dyskinesias.

Sense of agency is related to gamma band coupling in an inferior parietal-preSMA circuitry.

In the present study we tested whether sense of agency (SoA) is reflected by changes in coupling between right medio-frontal/supplementary motor area (SMA) and inferior parietal cortex (IPC). Twelve healthy adult volunteers participated in the study. They performed a variation of a line-drawing task (Nielsen, 1963; Fourneret and Jeannerod, 1998), in which they moved a cursor on a digital tablet with their right hand without seeing the hand.

10 Hz rTMS over right parietal cortex alters sense of agency during self-controlled movements.

A large body of fMRI and lesion-literature has provided evidence that the Inferior Parietal Cortex (IPC) is important for sensorimotor integration and sense of agency (SoA). We used repetitive transcranial magnetic stimulation (rTMS) to explore the role of the IPC during a validated SoA detection task. 12 healthy, right-handed adults were included.

The acute brain response to levodopa heralds dyskinesias in Parkinson disease.

Objective: In Parkinson disease (PD), long-term treatment with the dopamine precursor levodopa gradually induces involuntary "dyskinesia" movements. The neural mechanisms underlying the emergence of levodopa-induced dyskinesias in vivo are still poorly understood. Here, we applied functional magnetic resonance imaging (fMRI) to map the emergence of peak-of-dose dyskinesias in patients with PD.

Motivational tuning of fronto-subthalamic connectivity facilitates control of action impulses.

It is critical for survival to quickly respond to environmental stimuli with the most appropriate action. This task becomes most challenging when response tendencies induced by relevant and irrelevant stimulus features are in conflict, and have to be resolved in real time. Inputs from the pre-supplementary motor area (pre-SMA) and inferior frontal gyrus (IFG) to the subthalamic nucleus (STN) are thought to support this function, but the connectivity and causality of these regions in calibrating motor control has not been delineated.

Levodopa reinstates connectivity from prefrontal to premotor cortex during externally paced movement in Parkinson's disease.

Dopamine deficiency affects functional integration of activity in distributed neural regions. It has been suggested that lack of dopamine induces disruption of neural interactions between prefrontal and premotor areas, which might underlie impairment of motor control observed in patients with Parkinson's disease (PD). In this study we recorded cortical activity with high-density electroencephalography in 11 patients with PD as a pathological model of dopamine deficiency, and 13 healthy control subjects.

Seeing or moving in parallel: the premotor cortex does both during bimanual coordination, while the cerebellum monitors the behavioral instability of symmetric movements.

The underlying neural mechanisms of a perceptual bias for in-phase bimanual coordination movements are not well understood. In the present study, we measured brain activity with functional magnetic resonance imaging in healthy subjects during a task, where subjects performed bimanual index finger adduction-abduction movements symmetrically or in parallel with real-time congruent or incongruent visual feedback of the movements. One network, consisting of bilateral superior and middle frontal gyrus and supplementary motor area (SMA), was more active when subjects performed parallel movements, whereas a different network, involving bilateral dorsal premotor cortex (PMd), primary motor cortex, and SMA, was more active when subjects viewed parallel movements while performing either symmetrical or parallel movements.

Dopamine replacement modulates oscillatory coupling between premotor and motor cortical areas in Parkinson's disease.

Efficient neural communication between premotor and motor cortical areas is critical for manual motor control. Here, we used high-density electroencephalography to study cortical connectivity in patients with Parkinson's disease (PD) and age-matched healthy controls while they performed repetitive movements of the right index finger at maximal repetition rate. Multiple source beamformer analysis and dynamic causal modeling were used to assess oscillatory coupling between the lateral premotor cortex (lPM), supplementary motor area (SMA), and primary motor cortex (M1) in the contralateral hemisphere.

Modulation of proprioceptive feedback during functional electrical stimulation: an fMRI study.

Functional electrical stimulation (FES) is sometimes used as a therapeutic modality in motor rehabilitation to augment voluntary motor drive to effect movement that would otherwise not be possible through voluntary activation alone. Effective motor rehabilitation should require that the central nervous system integrate efferent commands and appropriate afferent information to update the internal models of acquired skills. Here, we investigate whether FES-evoked (FES-ev) and FES-assisted (FES-as) movement are associated with the normal integration of motor commands and sensory feedback in a group of healthy participants during functional magnetic resonance imaging (fMRI).