The influence of temporal predictability on express visuomotor responses.

Humans are able to generate target-directed visuomotor responses in less than 100 ms after stimulus onset. These "express" responses have been termed stimulus-locked responses (SLRs) and are proposed to be modulated by visuomotor transformations performed subcortically via the superior colliculus. Unfortunately, these responses have proven difficult to detect consistently across individuals.

Impact of Lower Limb Active Movement Training in Individuals With Spastic Type Cerebral Palsy on Neuromuscular Control Outcomes: A Systematic Review.

Cerebral Palsy (CP) is a non-progressive neurological condition that results in motor impairment which increases proximally to distally along the lower extremity (i.e., greatest impairment at the ankle).

Contralateral Effects of Unilateral Strength and Skill Training: Modified Delphi Consensus to Establish Key Aspects of Cross-Education.

Background: Cross-education refers to increased motor output (i.e., force generation, skill) of the opposite, untrained limb following a period of unilateral exercise training.

Mechanisms of Modulation of Automatic Scapulothoracic Muscle Contraction Timings.

Erected posture provides humans a large shoulder mobility that requires complex automatic muscle synergies to accomplish joint stability needs. This is evident in shoulder abduction, wherein the voluntary activation of glenohumeral muscles is coupled with an automatic recruitment of scapulothoracic muscles. Here, we investigated whether volitional modification of the scapular position, and dynamic scapular elevation, modulate the contraction timing of five shoulder muscles (middle deltoid, upper, middle and lower fiber of the trapezius, serratus anterior) during shoulder abduction.

Task Feedback Processing Differs Between Young and Older Adults in Visuomotor Rotation Learning Despite Similar Initial Adaptation and Savings.

Ageing has been suggested to affect sensorimotor adaptation by impairing explicit strategy use. Here we recorded electrophysiological (EEG) responses during visuomotor rotation in both young (n = 24) and older adults (n = 25), to investigate the neural processes that underpin putative age-related effects on adaptation. We measured the feedback related negativity (FRN) and the P3 in response to task-feedback, as electrophysiological markers of task error processing and outcome evaluation.

Riders Use Their Body Mass to Amplify Crank Power during Nonseated Ergometer Cycling.

Unlabelled: When cyclists ride off the saddle, their center of mass (CoM) appears to go through a rhythmic vertical oscillation during each crank cycle. Just like in walking and running, the pattern of CoM movement may have a significant effect on the mechanical power that needs to be generated and dissipated by muscle.

Purpose: To date, neither the CoM movement strategies during nonseated cycling nor the limb mechanics that allow this phenomenon to occur have been quantified.

De Novo Synthesized Estradiol: A Role in Modulating the Cerebellar Function.

The estrogen estradiol is a potent neuroactive steroid that may regulate brain structure and function. Although the effects of estradiol have been historically associated with gonadal secretion, the discovery that this steroid may be synthesized within the brain has expanded this traditional concept. Indeed, it is accepted that de novo synthesized estradiol in the nervous system (nE2) may modulate several aspects of neuronal physiology, including synaptic transmission and plasticity, thereby influencing a variety of behaviors.

Incidence of Hospitalization for Stroke in Queensland, Australia: Younger Adults at Risk.

Background: Trends in the incidence of stroke are important for health care planning. Information is particularly scarce in Australia, due to the paucity of studies with access to recent, large-scale, longitudinal datasets. In this paper we investigated the incidence of hospitalization for stroke by sex, age, and subtype in the whole State of Queensland (Australia).

Correction to: Effect of vibration characteristics and vibror arrangement on the tactile perception of the upper arm in healthy subjects and upper limb amputees.

The original article [1] contained an error whereby the captions to Fig. 3 and Fig. 8 were mistakenly interchanged.

Sensory inflow manipulation induces learning-like phenomena in motor behavior.

Purpose: Perceptual and goal-directed behaviors may be improved by repetitive sensory stimulations without practice-based training. Focal muscle vibration (f-MV) modulating the spatiotemporal properties of proprioceptive inflow is well-suited to investigate the effectiveness of sensory stimulation in influencing motor outcomes. Thus, in this study, we verified whether optimized f-MV stimulation patterns might affect motor control of upper limb movements.

Task Errors Drive Memories That Improve Sensorimotor Adaptation.

Traditional views of sensorimotor adaptation (i.e., adaptation of movements to perturbed sensory feedback) emphasize the role of automatic, implicit correction of sensory prediction errors.

The Mechanics of Seated and Nonseated Cycling at Very-High-Power Output: A Joint-Level Analysis.

Unlabelled: Cyclists frequently use a nonseated posture when accelerating, climbing steep hills, and sprinting; yet, the biomechanical difference between seated and nonseated cycling remains unclear.

Purpose: This study aimed to test the effects of posture (seated and nonseated) and cadence (70 and 120 rpm) on joint power contributions, effective mechanical advantage, and muscle activations within the leg during very-high-power output cycling.

Methods: Fifteen male participants rode on an instrumented ergometer at 50% of their individualized instantaneous maximal power (10.

High-density electromyographic assessment of stretch reflex activity during drop jumps from varying drop heights.

This study investigated how drop heights and their associated drop jump performance relate to stretch reflex modulations. Eleven male subjects performed ten drop jumps from each of three individually predetermined drop heights. These were the drop height resulting in maximal performance (OPT), as well as 10 cm below (LOW) and above (HIGH) maximal performance.

Effect of vibration characteristics and vibror arrangement on the tactile perception of the upper arm in healthy subjects and upper limb amputees.

Background: Vibrotactile stimulation is a promising venue in the field of prosthetics to retrain sensory feedback deficits following amputation. Discrimination is well established at the forearm level but not at the upper arm level. Moreover, the effects of combining vibration characteristics such as duration and intensity has never been investigated.

How optimal is bimanual tracking? The key role of hand coordination in space.

When coordinating two hands to achieve a common goal, the nervous system has to assign responsibility to each hand. Optimal control theory suggests that this problem is solved by minimizing costs such as the variability of movement and effort. However, the natural tendency to produce similar movements during bimanual tasks has been somewhat ignored by this approach.

Neuromuscular Properties of the Human Wrist Flexors as a Function of the Wrist Joint Angle.

The joint angle dependence of voluntary activation and twitch properties has been investigated for several human skeletal muscles. However, although they play a key role for hand function and possess a unique neural control compared to muscles surrounding other joint complexes, little is known about the wrist flexors innervated by the median nerve. Therefore, isometric voluntary and electrically evoked contractions of the wrist flexors were analyzed at three wrist joint angles (extension: -30°, neutral: 0°, flexion: 30°) to quantify the joint angle dependence of (i) voluntary activation (assessed via peripheral nerve stimulation and electromyography [EMG]), (ii) unpotentiated twitch torques, and (iii) potentiated twitch torques.

Reachy, a 3D-Printed Human-Like Robotic Arm as a Testbed for Human-Robot Control Strategies.

To this day, despite the increasing motor capability of robotic devices, elaborating efficient control strategies is still a key challenge in the field of humanoid robotic arms. In particular, providing a human "pilot" with efficient ways to drive such a robotic arm requires thorough testing prior to integration into a finished system. Additionally, when it is needed to preserve anatomical consistency between pilot and robot, such testing requires to employ devices showing human-like features.

A New Integrative Theory of Brain-Body-Ecosystem Medicine: From the Hippocratic Holistic View of Medicine to Our Modern Society.

Humans are increasingly aware that their fate will depend on the wisdom they apply in interacting with the ecosystem. Its health is defined as the condition in which the ecosystem can deliver and continuously renew its fundamental services. A healthy ecosystem allows optimal interactions between humans and the other biotic/abiotic components, and only in a healthy ecosystem can humans survive and efficiently reproduce.

Rapid recalibration of temporal order judgements: Response bias accounts for contradictory results.

Recent history influences subsequent perception, decision-making and motor behaviours. In this article, we address a discrepancy in the effects of recent sensory history on the perceived timing of auditory and visual stimuli. In the synchrony judgement (SJ) task, similar timing relationships in consecutive trials seem more synchronous (i.

The face-in-the-crowd effect: Threat detection versus iso-feature suppression and collinear facilitation.

Are people biologically prepared for the rapid detection of threat posed by an angry facial expression, even when it is conveyed in the form of a schematic line drawing? Based on visual search times, the current literature would suggest that the answer is yes. But are there low-level explanations for this effect? Here, we present visual search results for schematic faces using current best practice, based on a concentric search array and set size manipulation. Using this approach, we replicate the classic search advantage for angry over happy faces.

Motor Strategies Learned during Pain Are Sustained upon Pain-free Reexposure to Task.

Introduction: Pain affects movement planning and execution, and may interfere with the ability to learn new motor skills. Variations among previous studies suggest task-specific effects of pain on the initial acquisition and subsequent retention of motor strategies.

Methods: The present study assessed how acute pain in the anterior deltoid muscle affects movement accuracy of fast arm-reaching movements during force field perturbations and upon immediate pain-free repetition of the same task.

Microsaccades and covert attention: Evidence from a continuous, divided attention task.

A substantial question in understanding expert behavior is isolating where experts look, and which aspects of their environment they process. While tracking the position of gaze provides some insight into this process, our ability to attend covertly to regions of space other than the current point of fixation, severely limits the diagnostic power of such data. Over the past decade, evidence has emerged suggesting that microscopic eye movements present during periods of fixation may be linked to the spatial distribution of covert attention, potentially offering a powerful tool for studying expert behavior.

The effect of combined functional anaerobic and strength training on treadmill gait kinematics and kinetics in ambulatory young adults with cerebral palsy.

Background: Leg muscle weakness is a major impairment for individuals with cerebral palsy (CP) and is related to reduced functional capacity. Evidence is limited regarding the translation of strength improvements following conventional resistance training to improved gait outcomes.

Research Question: Does a combined functional anaerobic and lower limb strength training intervention improve gait kinematics and kinetics in individuals with CP aged 15-30 years? 17 young adults (21 ± 4 years, 9 males, GMFCS I = 11, II = 6) were randomized to 12 weeks, 3 sessions per week, of high intensity functional anaerobic and progressive resistance training of the lower limbs (n = 8), or a waitlist control group (n = 9).