In the last decades, robotics has emerged as a viable and safe tool to complement traditional therapy (see [10–12]) and it is a popular technology used by different stake- holders (Fig. 4). These robotic developments, primarily designed for delivering therapy, have also been pro- grammed to measure a great variety of parameters related to sensorimotor function (e.g., [3, 13, 14]) and they have been suggested as standard tools for sensorimotor assess- ments. Although an appealing idea, using therapeutic ro- bots for assessment is limited because each outcome measure is influenced by robot-specific factors such as the topology of the robot ’ s kinematic chain, control modal- ities, etc., which confound the results obtained from these tools. Nevertheless, robotic devices have the potential to become standards in assessments, but they must be specif- ically designed for the purpose of assessment, e.g., robotic dynamometers or ergometers.
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The ability of the central nervous systems (CNS) to change can also be used for therapeutic purposes, i.e., targeted plasticity  where weakened or lost functions can be strengthened. In healthy persons as well as in patients with median or ulnar nerve injuries, cutaneous anesthesia of the forearm has been shown to rapidly im- prove sensory function in the hand. The principle of temporary cutaneous anesthesia of adjacent body parts in combination with training was more effective in im- proving sensory function of the hand than training only [24,25]. The rapid improvement of sensory function and the enhanced effects 4 weeks after the last local anesthesia treatment [24,26], indicates that this interven- tion is clinically useful and relevant. Hypothetically, this principle could also be used to improve sensorimotor function of the knee. The ACL-injured knee may consti- tute a suitable model for this approach, because this
The importance of proprioception in musculoskeletal disorders has received increasing attention in recent decades in research and clinical work, including hand rehabilitation [18, 19]. However, feasible, affordable and accurate objective methods for assessment of proprio- ception are relatively scarce in the clinical setting. Clinical tests for assessment of wrist and finger proprio- ception often involves joint position sense measured with manual goniometer . In movement science la- boratories specific equipment are used for more accurate objective assessments of measures of position and move- ment sense, such as motor driven equipment and 3D motion capture systems [12, 21, 22]. These equipment are however not suitable for the general clinic due to cost and technological complexity involved. Grapho- nomic tests such as hand writing, drawing or tracking tasks with pen and paper techniques are valuable to evaluate sensorimotor function of the hand [23, 24]. These tests though involve movements with supported hand and/or pen and thereby also tactile input and movement adaptation due to the hand and pen contact with the surface. In this article, we suggest a feasible and affordable method for assessment of the movement sense of the wrist with unsupported freely moving hand by using a laser pointer and a novel software for swift and accurate objective evaluation of results. The object- ive of the study was to develop and conduct a primary evaluation of the validity of a clinical test with automa- tized scoring software for objective assessment of move- ment sense of the wrist.
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The present study used a reaching movement in order to identify differences in the sensorimotor function due to age. The nature of the task, without support of the limb against gravity, permitted us to explore deficits in motor coordination and also the influence of loss of muscle strength on motor per- formance. Our results showed significant differences between group 1 (20–40 years) and group 3 (61–80 years) in most of the measured parameters. Furthermore, this difference was not the same for both arms (dominant and non-dominant); but, in most cases, it was greater for the dominant arm.
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We were able to quantify improvements in measures of dynamic, but not static, sensorimotor function during the initial three weeks of recovery from TKA or THA. Sensorimotor improvements were independent of sen- sorimotor training volume, as sensorimotor performance did not differ with weekly training volumes of two, four or six sessions. Thus, in contrast to common clinical practise, greater volume of sensorimotor training during rehabilitation does not necessarily lead to better sensori- motor function. Further research investigating the effect of training volume and its long-term effects are needed, however, before definitive recommendations regarding op- timal training stimulus (magnitude, frequency, duration) can be formulated.
A study by Chitra & Das (2015) supports present study. They studied the effect of PNF technique on core strength in patient with type 2 diabetes. The result of the study showed a statistical significance in the core strength (p = <0.001). After PNF technique there was significant im- provement in core strength in patient with diabetes. The results of a study by Kumar S (2012) are also found to be relevant with present study. He assessed the effect of PNF techniques on the gait parameters and functional mo- bility in hemiplegic patients. The PNF techniques helped improving the gait and mobility of these patients by im- proving sensorimotor function.
The primary aim of the ERNI-HSF Research Networking Programme is to establish an interdisciplinary scientific forum that can drive forward our understanding of hu- man sensorimotor function in health and disease. A key aspect of this forum is the foundation of a pan-European research network that makes possible collaborative work practices that could not be achieved by individual scientists working alone. The activities of ERNI-HSF are facilitated by a Steering Committee, the members of which are drawn from a wide range of scientific disciplines relevant to the investigation of human sen- sorimotor function in health and disease. An important function of the Steering Committee is to identify thematic topics or issues that are considered to be critical for initiating major scientific advances, and to oversee the organisation of appropriate technical workshops and scientific meetings.
It has however been observed that in the real musculoskeletal system, the existence of spring-like tendons means that tendon-length itself must be known (or calculated) for the motor system to in turn know the current state of the body. Given the fact that tendons are passive structures and exhibit nonlinear spring-like behaviour, force at the muscle-tendon junction is proportional to the product of tendon stiffness and (a power law relation of) tendon length. Therefore an alternative interpretation of tendon signals considers Golgi tendon organs as in fact signalling tendon length. This role has been proposed explicitly in a recent modelling study (Kistemaker et al., 2012). Joint receptors were originally thought to fulfill the role now ascribed to muscle spindles, that is to provide necessary information about joint angle change across the entire range of a joint. However, subsequent studies identified that in fact joint receptors signal identically for opposite ends of the joint range, and also feature low/absent mid-range responses (Burgess et al., 1982). In addition, both temporary and permanent disruption of receptor function via anaesthesis (Clark et al., 1979) or surgically-mediated destruction (Grigg et al., 1973) have been shown to leave move- ment perception and generation relatively unimpaired. Thus joint receptors have been relegated to subsidiary roles, perhaps as limit detectors signalling extreme joint angles (Ferrell et al., 1987).
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; Dassonville et al. 1997; Mattay et al. 1997; Singh et al. 1998a&b). This ipsilateral activation was found in the precentral region (Singh et al. 1998a&b). In addition, bilateral activation has been demonstrated in the primary motor cortices with simple and more complex movements of both hands in subjects who are left-handed or ambidextrous, compared to unilateral activation with dominant hand movement in right-handed subjects (Dassonville et al. 1997). Such bilateral activation may be less significant than unilateral activation (Berkelbach van der Sprenkel et al. 1999). In addition, other studies with right-handed subjects have reported no difference between complex finger to thumb opposition motor studies involving the left and right hand with fMRl (Roth et al. 1996), both sides of the body inducing contra- and ipsilateral activation in the primary motor cortex. One study has reported no consistent ipsilateral activation in right-handed volunteers performing what they describe as a simple sensorimotor hand task of unilateral middle finger tapping with either hand (Boecker et al. 1994). The diversity in the results from these studies does not appear to be dependent on the complexity of the motor task.
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This study investigated the sensorimotor function of dif- ferent body sites in participants with recurrent ankle in- juries. As noted in recent systematic reviews [9, 10], postural stability measures in single-leg stance did not discriminate between participants with CAI and those without, as well as between the limb with recurrent sprains versus the unaffected limb in the CAI group. It should be noted, however, that while the measure of static postural stability may not be sensitive enough to detect deficits associated with CAI, more dynamic as- sessments, such as the single-leg-hop stabilisation man- euver, may have the ability to defer between individuals with CAI and individuals with stable ankles [28, 29]. In addition, reports of postural assessment through the Balance Error Scoring System have also shown promise in detecting differences between those with and without CAI .
Recent studies have indicated an enhancement of motor learning (acquisition and retention of motor skills) [15–18], as well as cognitive function (memory, attention, and concentration)  in healthy adults when aerobic exercise (AE) was associated with training of specific abilities (motor or cognitive training). According to the literature, the sequence and intensity of AE impact the learning process  and might facilitate improvements in motor function or motor memory consolidation processes. The retention of motor tasks improves when performed 15 min after high-intensity interval AE compared to moderate and low-intensity exercise [21, 22]. Learning was greater when AE was achieved using a bicycle compared to a treadmill . A recent study demonstrated that AE on a cycle ergometer, when associated with task-specific training, improves the sensorimotor function of the upper limb . Currently, there is more evidence supporting AE as a method of priming lower limb motor recovery [24, 25]. However, to date, no studies have investigated the effect of AE on fine motor control or relearning of lost upper extremity movement using motion analysis and manual dexterity evaluation .
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Background: Low back pain (LBP) is a recognized public health problem, impacting up to 80% of US adults at some point in their lives. Patients with LBP are utilizing integrative health care such as spinal manipulation (SM). SM is the therapeutic application of a load to specific body tissues or structures and can be divided into two broad categories: SM with a high-velocity low-amplitude load, or an impulse “thrust”, (HVLA-SM) and SM with a low-velocity variable- amplitude load (LVVA-SM). There is evidence that sensorimotor function in people with LBP is altered. This study evaluates the sensorimotor function in the lumbopelvic region, as measured by postural sway, response to sudden load and repositioning accuracy, following SM to the lumbar and pelvic region when compared to a sham treatment. Methods/Design: A total of 219 participants with acute, subacute or chronic low back pain are being recruited from the Quad Cities area located in Iowa and Illinois. They are allocated through a minimization algorithm in a 1:1:1 ratio to receive either 13 HVLA-SM treatments over 6 weeks, 13 LVVA-SM treatments over 6 weeks or 2 weeks of a sham treatment followed by 4 weeks of full spine “doctor’s choice” SM. Sensorimotor function tests are performed before and immediately after treatment at baseline, week 2 and week 6. Self-report outcome assessments are also collected. The primary aims of this study are to 1) determine immediate pre to post changes in sensorimotor function as measured by postural sway following delivery of a single HVLA-SM or LVVA-SM treatment when compared to a sham treatment and 2) to determine changes from baseline to 2 weeks (4 treatments) of HVLA-SM or LVVA-SM compared to a sham treatment. Secondary aims include changes in response to sudden loads and lumbar repositioning accuracy at these endpoints, estimating sensorimotor function in the SM groups after 6 weeks of treatment, and exploring if changes in sensorimotor function are associated with changes in self-report outcome assessments.
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The ability of an animal to detect and respond to changes in the environment is crucial to its survival. However, two elements of sensorimotor control – the time required to respond to a stimulus (responsiveness) and the precision of stimulus detection and response production (resolution) – are inherently limited by a competition for space in peripheral nerves and muscles. These limitations only become more acute as animal size increases. In this paper, we investigated whether the physiology of giraffes has found unique solutions for maintaining sensorimotor performance in order to compensate for their extreme size. To examine responsiveness, we quantified three major sources of delay: nerve conduction delay, muscle electromechanical delay and force generation delay. To examine resolution, we quantified the number and size distribution of nerve fibers in the sciatic nerve. Rather than possessing a particularly unique sensorimotor system, we found that our measurements in giraffes were broadly comparable to size-dependent trends seen across other terrestrial mammals. Consequently, both giraffes and other large animals must contend with greater sensorimotor delays and lower innervation density in comparison to smaller animals. Because of their unconventional leg length, giraffes may experience even longer delays compared with other animals of the same mass when sensing distal stimuli. While there are certainly advantages to being tall, there appear to be challenges as well – our results suggest that giraffes are less able to precisely and accurately sense and respond to stimuli using feedback alone, particularly when moving quickly.
The optimal control approach to understanding movements was first applied to muscles, where the redundancy o f the system and practical considerations limit the direct investigation o f the force produced by each muscle acting at a joint, particularly in human subjects. This means that the optimal muscle force distribution used by the CNS cannot be directly observed, and distinguishing between different possible cost functions is not simple. MacConaill (1967) suggested that the motor system might activate muscles in order to minimise the total muscle force required to produce a desired torque (force multiplied by moment arm), meaning that the muscles with the largest moment arm should be fully activated before muscles with a smaller moment arm are used. However, both data (Basmajian and Latif, 1957) and simulations (Yeo, 1976) suggest this cost function is not used in the motor system. Some investigators have proposed cost functions based on fatigue or endurance (Crowninshield and Brand, 1981; Dul et al., 1984a; Dul et al., 1984b). In contrast, several studies suggest that muscle force squared or muscle stress (force divided by physiological cross sectional area) squared should be minimised, for both upper limb (van Bolhuis and Gielen, 1999; Gomi, 2000) and lower limb muscles (Pedotti et al., 1978). All these cost functions are mathematically similar, and it has proved difficult to distinguish between them (Collins, 1995; van Bolhuis and Gielen, 1 9 9 9 )........................................................................................
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well as the ability of the muscular components to respond to a given motor command. The perceived levels of force generated are presumably a function of the ensemble of proprioceptive afferent feedback from the entire body, although the predominant input is probably derived more directly from the working joints and associated muscles and tendons (Jones, 1986). Assuming that no changes occurred in the muscular components over time, then the altered force output observed in the present study could reflect space-flight-induced changes in afferent input and its ‘interpretation’. Although some decrement in the force potential, as measured from single muscle fibers, was reported for these subjects during this space flight mission (Widrick et al., 1999) and Narici et al. (Narici et al., 1997) found a reduced peak torque following electrical
The sensorimotor theory’s alternative conception is founded on the claim that conscious visual experience does not comprise a richly detailed representation of the visual scene. A later step will be to re-describe visual phenomenology and the processes that enable it with attention to the fact that perceivers do not take visual experience to be sparsely furnished. The starting point, however, is to establish that the visual system does not process large amounts of detail all at once. O&N, pursuing this thesis, cite a range of empirical work, including work on inattentional blindness (Wolfe, 1997), the best known example of which is the ‘invisible gorilla’ test (Simons and Chabris, 1999). The experiment features a short video of a basketball game with teams dressed respectively in black and white, each passing a separate basketball amongst themselves. Participants are shown the clip and asked to count how many times the players in white pass the ball, a task which requires close attention given the fast-moving action and the distracting influence of the team in black. Midway through the clip, a person in a gorilla costume enters the scene, walks casually through the middle of the game and makes a chest-beating motion. When asked if they had noticed anything out of the ordinary, around half the participants in Simons and Chabris’ study failed to report noticing this take place. There are multiple ways to interpret this data, among which is the suggestion that participants were visually aware of the gorilla but did not attend to it, and therefore failed to remember it when questioned. However, the work supports the claim that perceivers do not experience unattended detail from the visual scene.
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behavioural and neurophysiological effects of AO+MI. Indeed, in the only available study to date contrasting behavioural outcomes of AO+MI with MI (Taube et al., 2014), the practice effects of these two conditions did not significantly differ (but see their discussion for caveats). The present study, however, provides two pieces of evidence against this view: In the behavioural data, synchronised AO+MI produced an imitation bias almost twice as large as pure MI. Further studies are now needed to confirm or specify this finding in a range of other motor tasks. In addition, the electrophysiological data indeed mirrored the behavioural data in this respect, that is, neural activity in both primary sensorimotor and posterior parietal regions was markedly stronger for AO+MI than for pure MI. These novel findings provide strong and convergent support for the dual-simulation account of AO+MI. Supporting this further, we also found that the ERD intensities during pure AO and pure MI were fairly similar in the present task, with only slightly stronger activity during pure MI overall.
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In recent years, much attention has been focused on the notion that having access to a corresponding functional motor representa- tion is a crucial prerequisite for the ability to predict observed actions (e.g. Cannon & Woodward, 2012; Cannon et al., 2012; Falck-Ytter et al., 2006; Gredebäck & Kochukhova, 2010; Gredebäck et al., 2009; Kanakogi & Itakura, 2011; Stapel et al., 2016). As a result of this focus on the role of motor experience in action prediction, very little research has been conducted to inves- tigate alternative mechanisms through which infants can under- stand and predict others’ actions while their motor repertoire is still developing. The results of the present study show that infants are able to make surprisingly fine-grained predictions about the kinematics of human actions that are outside their motor reper- toire, and that the sensorimotor cortex may play a role in this pre- dictive tracking process. Pre-walking infants distinguished between correctly and incorrectly continued stepping actions that were presented from a visually familiar perspective only, suggest- ing that visual experience alone may be sufficient to support suc- cessful predictive action tracking. These findings are consistent with previous studies that have demonstrated that infants can pre- dict events for which they do not have access to a corresponding functional motor representation (i.e., non-human actions such as self-propelled objects and claws) (Biro, 2013; Southgate & Begus, 2013) and that suggest that observational experience can facilitate the activation of motor representations for unfamiliar actions (Boyer & Bertenthal, 2016). The present study extends these results by demonstrating that infants can generate real-time action pre- dictions for human actions that are not yet part of their motor repertoire. Taken together, these findings provide evidence against the idea that predictive tracking of human actions requires motor experience with the observed actions.
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The context estimation perspective may also be useful in linking the putative mo tor and cognitive functions of the cerebellum. Even though there is no consensus as to its exact role in motor control (see also Section 8.4), the cerebellum’s neu- roanatomical placement — neither direct input from sensory receptors, nor direct output to motoneurons — suits it ideally for context estimation operations. The highly regular architecture of cerebellar cortex forms distinct parallel loops with most cortical areas (Middleton and Strick 2000). It is particularly the more lateral parts of cerebellar cortex th at have been implicated in higher cognitive functions such as language (Leiner et al. 1991). Further, neuropsychological abnormalities in patients with cerebellar cortical atrophy have included impaired executive function dem onstrated by increased planning time when performing the Tower of Hanoi test and poor performance on tests of fluency. Cerebellar patients also have difficulty on tasks th a t require shifts of attention between different modalities (Schmahmann
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Evidence-based guidelines for therapy aimed at restor- ing motor impairments do exist but, as yet, therapy- mediating somatosensory impairments are still scarce. A 2010 Cochrane review by Doyle et al.  on “interven- tions of sensory impairments in the upper limb after stroke” concluded that “there is insufficient evidence to reach conclusions about the effects of interventions in- cluded in this review.” In 2011, results from a random- ized controlled trial (RCT) by Carey et al.  investigating the effect of upper limb sensory discrimin- ation training on somatosensory function after stroke showed a significant effect of sensory discrimination training compared to general sensory exposure in chronic stroke . Although the evidence for the effect of somatosensory therapy on somatosensory function is increasing, to our knowledge, only two case-series stud- ies have investigated its effect on motor function [8, 9]. A preliminary study reported results of two patients who received sensorimotor stimulation training consisting of passive mobilization, sensory stimulation by means of an electric toothbrush for vibration, and position training for proprioception. The box and blocks test and the 10-s test were conducted after each session and showed im- provements . Another preliminary study reported a case series of two patients receiving a sensorimotor pro- gram consisting of manipulation tasks with a sensory discrimination aspect, such as sorting plastic eggs of dif- ferent weights . Also, the latter study reported im- provement in motor function after training. Further, neural sensory reorganization was found on functional magnetic resonance imaging (fMRI) and brain volume measurements for both participants after the sensori- motor discrimination program .
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