Motor Control

An epidemiological study of Attention Deficit / Hyperactivity Disorder (ADHD) suggests that the prevalence may be two to three times higher than the figure of 3 ± 5% often cited. In addition, the data suggest that both underdiagnosis and overdiagnosis occur frequently. Rodent animal models of ADHD, like the Spontaneously Hypertensive Rat (SHR) and other rat models such as those with chemical and radiationinduced brain lesions and cerebellar stunting, and the Coloboma mouse model exhibit clear similarities with several aspects of the human disorder and should prove useful in studying specific traits. Operant behavioral tasks that model learning, short -term memory and simple discriminations are sensitive to ADHD and methylphenidate has been shown to normalize ADHD performance in a short -term memory task. Recent findings challenge not only the current postulate that response inhibition is a unique deficit in ADHD, but also the concepts of ADHD and its treatment, which presume intact perceptual abilities. Time perception deficits may account, in part, for the excessive variability in motor response times on speeded reaction time tasks, motor control problems and motor clumsiness associated with ADHD. The Multimodality Treatment Study of ADHD (MTA) provided data suggesting that pharmacological interventions that included systematic and frequent follow -up with parents and teachers, with or without psychosocial interventions, are superior to psychosocial interventions or standard community care alone. Additionally, the MTA was one of the first studies to demonstrate benefits of multimodal and pharmacological interventions lasting longer than 1 year. Imaging studies have demonstrated differences in brain areas in children with ADHD: anterior corpus callosum, right anterior white matter, and cerebellar volumes are all decreased in children with ADHD and there is less brain asymmetry in ADHD subjects. Additionally, functional imaging studies, coupled with pharmacological manipulations, suggest decreased blood flow and energy utilization in prefrontal cortex and striatum, and the dysregulation of catecholamine systems in persons with ADHD. D (M.G. Paule).

Many aspects of attention decline with aging. There is a current debate on how aging also affects sustained attention. In this study, we contribute to this debate by meta-analytically comparing performance on the go/no-go Sustained Attention to Response Task (SART) in younger and older adults. We included only studies in which the SART had a low proportion of no-go trials (5%–30%), there was a random or quasirandom stimulus presentation, and data on both healthy younger and older adults were available. A total of 12 studies were suitable with 832 younger adults and 690 older adults. Results showed that older adults were slower than younger adults on go trials (g = 1, 95% CI [.72, 1.27]) and more accurate than younger adults on no-go trials (g = .59, 95% CI [.32, .85]). Moreover, older adults were slower after a no-go error than younger adults (g = .79, 95% CI [.60, .99]). These results are compatible with an age-related processing speed deficit, mostly suggested by longer go RTs, bu...

The influence of a person’s brain type and the segmental coordination used in free throw basketball shooting was evaluated by video analysis. Fifteen subjects were classified using a brain typing inventory with 16 categories. Markers were placed on selected joints of the participants who performed 5 free throws, videotaped in the sagittal plane at 60 Hz. Three participants having a brain type on each end of the personality spectrum were selected for film analysis. The shooting coordinate data was analyzed using an Ariel APAS. The time and maximal angular velocities were calculated for selected joints. The order of joint sequencing was determined for the brain types. Subjects who were brain type (BCIL/INTJ) tended to use multiple joint sequencing and those of brain type (FEAR/ESFP) used primarily large segments.

falls, standing balance and obstacle avoidance performance, and balance confi dence scores. Results: The number of falls in the exercise group decreased by 46% (incidence rate ratio (IRR) 0.54, 95% confi dence interval (CI) 0.36-0.79) compared to the number of falls during the baseline period and by 46% (IRR 0.54, 95% CI 0.34-0.86) compared to the control group. Obstacle avoidance success rates improved signifi cantly more in the exercise group (on average 12%) compared to the control group (on average 6%). Quiet stance and weight-shifting measures did not show signifi cant effects of exercise. The exercise group also had a 6% increase of balance confi dence scores. Conclusion: The Nijmegen Falls Prevention Program was effective in reducing the incidence of falls in otherwise healthy elderly. There was no evidence of improved control of posture as a mechanism underlying this result. In contrast, an obstacle avoidance task indicated that subjects improved their performance. Laboratory obstacle avoidance tests may therefore be better instruments to evaluate future fall prevention studies than posturographic balance assessments.

The aim of this paper is to present a new fuzzy control scheme for real time drive efficiency improvement by the adaptive flux reduction at light loads during steady states and by the optimum flux recovery during transient states. The optimum flux recovery instead of the rated flux does not sacrifice the drive dynamic response since the torque capacity remains the same and accelerates the search convergence in steady states. The control scheme is cooperated with an Indirect-Field-Oriented-Control (IFOC) motor drive. The design of the new fuzzy control scheme is focused to recognize the motor state operation in order to control under the corresponding circumstances. The proposed fuzzy control scheme includes three main units: one Fuzzy-Logic-Search Controller FLSC1, one Fuzzy-Logic-Controller FLC2 and a State detector unit. The State detector unit decides which of the FLSC1 or FLC2 controllers is used, in accordance to the operation circumstances. The fuzzy controllers utilize the stator flux-producing current component into d-q reference frame (stator current direct axis i sd) as control variable, in order to estimate the next optimal change of Δi sd. The drive efficiency improvement and the drive dynamic response is currently validated in laboratory using an experimental array of a 3phase 1 Hp induction motor drive. The control scheme is implemented using the platform eZdsp from Digital Spectrum based on the fixed point 32 bit DSP TMS320F2812 from TI.

An important goal in rehabilitation engineering is to develop technology that allows individuals with severe motor impairment to practice arm movement without continuous supervision from a rehabilitation therapist. This paper describes the development of such a system, called Therapy WREX or ("T-WREX"). The system consists of an orthosis that assists in arm movement across a large workspace, a grip sensor that detects hand grip pressure, and software that simulates functional activities. The arm orthosis is an instrumented, adult-sized version of the Wilmington Robotic Exoskeleton (WREX), which is a five degrees-of-freedom mechanism that passively counterbalances the weight of the arm using elastic bands. After providing a detailed design description of T-WREX, this paper describes two pilot studies of the system's capabilities. The first study demonstrated that individuals with chronic stroke whose arm function is compromised in a normal gravity environment can perform reaching and drawing movements while using T-WREX. The second study demonstrated that exercising the affected arm of five people with chronic stroke with T-WREX over an eight week period improved unassisted movement ability (mean change in Fugl-Meyer score was 5 points 2 SD; mean change in range of motion of reaching was 10%, 0 001). These results demonstrate the feasibility of automating upper-extremity rehabilitation therapy for people with severe stroke using passive gravity assistance, a grip sensor, and simple virtual reality software.

This article focuses on raising concern that anxiety-performance relationship theory has insufficiently catered for motoric issues during, primarily, closed and self-paced skill execution (e.g., long jump and javelin throw). Following a review of current theory, we address the under-consideration of motoric issues by extending the three-dimensional model put forward by Cheng, Hardy, and Markland (2009) ('Toward a three-dimensional conceptualization of performance anxiety: Rationale and initial measurement development, Psychology of Sport and Exercise, 10, 271-278). This fourth dimension, termed skill establishment, comprises the level and consistency of movement automaticity together with a performer's confidence in this specific process, as providing a degree of robustness against negative anxiety effects. To exemplify this motoric influence, we then offer insight regarding current theories' misrepresentation that a self-focus of attention toward an already well-learned skill always leads to a negative performance effect. In doing so, we draw upon applied literature to distinguish between positive and negative self-foci and suggest that on what and how a performer directs their attention is crucial to the interaction with skill establishment and, therefore, performance. Finally, implications for skill acquisition research are provided. Accordingly, we suggest a positive potential flow from applied/ translational to fundamental/theory-generating research in sport which can serve to freshen and usefully redirect investigation into this long-considered but still insufficiently understood concept.

Recent research in instrumental conditioning has focused on the striatum, particularly the role of the dorsal striatum in the learning processes that contribute to instrumental performance in rats. This research has found evidence of what appear to be parallel, functionally and anatomically distinct circuits involving dorsomedial striatum (DMS) and dorsolateral striatum (DLS) that contribute to two independent instrumental learning processes. Evidence suggests that the formation of the critical action-outcome associations mediating goal-directed action are localized to the dorsomedial striatum, whereas the sensorimotor connections that control the performance of habitual actions are localized to the dorsolateral striatum. In addition to the dorsal striatum, these learning processes appear to engage distinct corticostriatal networks and to be embedded in a complex of converging and partially segregated loops that constitute the cortico-striatal thalamo-cortical feedback circuit. As the entry point for the basal ganglia, cortical circuits involving the dorsal striatum are clearly in a position to control a variety of motor functions but, as recent studies of various neurodegenerative disorders have made clear, they are also involved in a number of cognitive and executive functions including action selection, planning, and decision-making.

Children with cerebral palsy (CP) have difficulty controlling and coordinating voluntary muscle, which results in poor selective control of muscle activity. Children with spastic CP completed ankle selective motor control exercises using a virtual reality (VR) exercise system and conventional (Conv) exercises. Ankle movements were recorded with an electrogoniometer. Children and their parents were asked to comment on their interest in the exercise programs. Greater fun and enjoyment were expressed during the VR exercises. Children completed more repetitions of the Conv exercises, but the range of motion and hold time in the stretched position were greater during VR exercises. These data suggest that using VR to elicit or guide exercise may improve exercise compliance and enhance exercise effectiveness.

Kinematic recordings in a reach and drop task were compared between 12 preschool children with autism without mental retardation and 12 gender and age-matched normally developing children. Our aim was to investigate whether motor anomalies in autism may depend more on a planning ability dysfunction or on a motor control deficit. Planning and control processes were separately investigated by examining kinematic recordings divided into primary movement-(planning-based) and corrective submovement-(control-based) phases.

In spite of the detailed anatomical knowledge available, the functional significance of the cerebellar wiring diagram is still obscure. Since there arc no variations in the anatomy throughout the whole cortical plane, it is plausible to assume that the basic operation is the same in all parts of the cerebellum. The 'wiring' suggests that local activity must depend on the spatio-temporal organization of the inputs. Neocortical input reaches the cerebellar cortex from nearly all cortical areas via mossy fibers terminating on the granular cells. We simulated such an input to the granular layer in acute slices of rat cerebellar cortex using an array of II stimulating electrodes. By successively switching the stimulus current from one electrode to the next, a 'moving' input to the granular layer is simulated. Our experiments show that the cerebellar cortex is specifically activated by 'moving' stimuli applied to the granular layer. The activation is a function of 'movement' direction and velocity. Thus, it enables the cerebellar cortex to act as a movement detector. Such behavior has previously been postulated on anatomical grounds [Braitenberg,

EMG responses elicited by sudden onset of free fall and a startling auditory stimulus were investigated in healthy subjects while lying on a couch with their eyes closed. Muscle responses were recorded from masseter (V cranial nerve), orbicularis oculi and mentalis (VII nerve) and sternomastoid and trapezoid (XI nerve). A similar sequence of muscle activation and absolute latencies occurred in response to both stimulus modalities, consisting of a blink (30 msec) followed simultaneously by mentalis, sternomastoid and trapezoid (55 msec). Masseter could either be simultaneously activated with the latter muscles or follow after a delay of 10-20 msec. A patient with bilateral cochleo-vestibular nerve section had responses at comparable latencies in the free fall experiment. The similarities between the reaction to free fall and a startling auditory stimulus indicate that the early response to free fall constitutes a startle and that various stimuli converge onto a common response genera...

Future life pictures humans having intelligent humanoid robotic systems taking part in their everyday life. Thus researchers strive to supply robots with an adequate artificial intelligence in order to achieve a natural and intuitive interaction between human being and robotic system. Within the German Humanoid Project we focus on learning and cooperating multimodal robotic systems. In this paper we present a first cognitive architecture for our humanoid robot: The architecture is a mixture of a hierarchical three-layered form on the one hand and a composition of behaviour-specific modules on the other hand. Perception, learning, planning of actions, motor control, and human-like communication play an important role in the robotic system and are embedded step by step in our architecture.

Background: Muscle jerks and their cortical correlates usually occur abruptly and arrhythmically in patients with positive or negative myoclonus. However, there have been several reports in which oscillatory pre-myoclonic cortical discharges occur in patients with repetitive myoclonus (

Objectives: We investigated intra-and inter-evaluator reliability to quantify spasticity based on the tonic stretch reflex threshold (TSRT) and the correlation between TSRT and resistance to stretch. Methods: Spasticity was evaluated in 20 subjects with chronic stroke-related spasticity using a portable device and the Modified Ashworth Scale (MAS). Evaluations were done on 2 days, by three evaluators. Biceps brachii EMG signals and elbow displacement were recorded during 20 elbow stretches applied at different velocities for each evaluation. Velocity-dependent dynamic stretch reflex thresholds (angle where EMG signal increased in the biceps for a given velocity of stretch) were recorded. These values were used to compute TSRT (excitability of motoneurons at 0°/s). Spasticity was also measured with MAS. Results: Reliability was moderately good for subjects with moderate to high spasticity (intra-evaluator: 0.46-0.68, and inter-evaluator: 0.53-0.68). The TSRT measure of spasticity did not correlate with resistance to stretch (MAS). Conclusions: TSRT may be a more representative measure for subjects with moderate to high spasticity. Further improvements are suggested for the portable device in order to quantify all the levels of spasticity. Significance: TSRT may be an alternative clinical measure to current clinical scales.

Parkinson disease is a progressive neurological condition characterised by hypokinesia (reduced movement), akinesia (absent movement), tremor, rigidity and postural instability. These movement disorders are associated with a slow short-stepped, shuing gait pattern. Analysis of the biomechanics of gait in response to medication, visual cues, attentional strategies and neurosurgery provides insight into the nature of the motor control de®cit in Parkinson disease and the ecacy of current therapeutic interventions. In this article we supplement a critical evaluation of the Parkinson disease gait literature with two case examples. The ®rst case describes the kinematic gait response of an individual with Parkinson disease to visual cues in the``o'' phase of the levodopa medication cycle. The second case investigates the biomechanics and motor control of turning during walking in a patient with Parkinson disease compared with elderly and young control subjects. The results are interpreted in light of the need for gait analysis to investigate complex functional walking tasks rather than con®ning assessment to straight line walking, which has been the trend to date. Ó

... Sensory information comes from a Laser Range Finder also developed by the author [6]. Range data are made up of hundreds of 2D relative coordinate points of targets in the field of view of the sensor camera, already filtered and grouped ... [2] JC Garcı́a, M. Marrón, JA Garcı́a, J ...

This work investigates the design of a new method to evaluate the importance of visual elements taken into account by a handball goalkeeper facing a thrower. Virtual reality was used to design and reproduce standardised situations in a controlled environment. Under such conditions, it was possible to isolate for investigation one visual element in the thrower's gestures. The goalkeeper's movements were recorded in order to compare his reactions to two separate throws where only one visual element was modified. Our systems allowed us to measure and record the effects of small changes in the thrower's movements. With the numerical values we obtained from our results we were able to come up with a scale of significance for each isolated element. These preliminary results look promising for neuroscience, allowing us to better understand the strategies used in duel situations.

The present paper proposes a technical analysis method for extracting information about movement patterning in studies of motor control, based on a cluster analysis of movement kinematics. In a tutorial fashion, data from three different experiments are presented to exemplify and validate the technical method. When applied to three different basketball-shooting techniques, the method clearly distinguished between the different patterns. When applied to a cyclical wrist supination-pronation task, the cluster analysis provided the same results as an analysis using the conventional discrete relative phase measure. Finally, when analyzing throwing performance constrained by distance to target, the method grouped movement patterns together according to throwing distance. In conclusion, the proposed technical method provides a valuable tool to improve understanding of coordination and control in different movement models, including multiarticular actions.

Recent advances in the fields of cerebral blood flow analysis, single cell brain recordings and human motor performance have elaborated the unique characteristics of movement disturbance in Parkinson's disease. These lines of research suggest that the basal ganglia have two major functions in motor control. The first is concerned with the maintenance of preparedness for movement, known as 'motor set'. The second function is the provision of internal motor cues which act to trigger submovements in well learned sequences. Disturbance to these mechanisms leads to the classic hallmarks of Parkinson's disease: hypokinesia, akinesia, rigidity and tremor.

Optimal control models of biological movements introduce external task factors to specify the pace of movements. Here, we present the dual to the principle of optimality based on a conserved quantity, called “drive”, that represents the influence of internal motivation level on movement pace. Optimal control and drive conservation provide equivalent descriptions for the regularities observed within individual movements. For regularities across movements, drive conservation predicts a previously unidentified scaling law between the overall size and speed of various self-paced hand movements in the absence of any external tasks, which we confirmed with psychophysical experiments. Drive can be interpreted as a high-level control variable that sets the overall pace of movements and may be represented in the brain as the tonic levels of neuromodulators that control the level of internal motivation, thus providing insights into how internal states affect biological motor control.

Survivors of spinal cord injury need to reorganize their residual body movements for interacting with assistive devices and performing activities that used to be easy and natural. To investigate movement reorganization, we asked subjects with high-level spinal cord injury (SCI) and unimpaired subjects to control a cursor on a screen by performing upper-body motions. While this task would be normally accomplished by operating a computer mouse, here shoulder motions were mapped into the cursor position. Both the control and the SCI subjects were rapidly able to reorganize their movements and to successfully control the cursor. The majority of the subjects in both groups were successful in reducing the movements that were not effective at producing cursor motions. This is inconsistent with the hypothesis that the control system is merely concerned with the accurate acquisition of the targets and is unconcerned with motions that are not relevant to this goal. In contrast, our findings suggest that subjects can learn to reorganize coordination so as to increase the correspondence between the subspace of their upper-body motions with the plane in which the controlled cursor moves. This is effectively equivalent to constructing an inverse internal model of the map from body motions to cursor motions, established by the experiment. These results are relevant to the development of interfaces for assistive devices that optimize the use of residual voluntary control and enhance the learning process in disabled users, searching for an easily learnable map between their body motor space and control space of the device.

Research on the focus of attention has begun exploring the physiological changes that underlie the difference between internal and external foci of attention. However, previous electromyography studies have used dynamic tasks, making it difficult to interpret electrophysiological data. The authors analyzed how the focus of attention affects a subject's ability to perform an isometric force production task (focus was directed either at the force platform or the muscles responsible for force production). Subjects received practice without attentional focus instructions and then completed blocks of trials with an external and internal attentional focus separately. An external focus led to significantly less error overall and reduced surface electromyography activity with lower median power frequencies in the antagonist muscle, but attentional focus had no effects on the agonist muscle. Thus, an external focus of attention led to more efficient motor unit recruitment patterns (reduced cocontraction) and improved performance. Posttest surveys revealed subjects were aware of their improved performance with an external focus.

Introduction: The term “cross-education” describes the perfomance improvement, both in motor control and strength, of a limb after training the opposite. Despite its current interest, there is no consensus on many concepts of the transfer of a visuomotor skill. The aim of the present research was to review the current literature on the phenomenon of cross-education in visuomotor skills in order to determine the magnitude of transference and its relationships with the context of the intervention. Results: A literature search was conducted during December 2019 in the databases Pubmed, CINAHL, MEDLINE, Web of Science, SPORTdiscus and Scopus. The descriptors “Motor ability” and “Motor skill” were used, in addition to the keywords “Motor control”, “skill”, “Task”, “cross over effect”, “cross exercise”, “contralateral learning”, “inter limb transfer “,” cross transfer “,” cross education “. After applying the inclusion and exclusion criteria, a total of 19 articles were obtained for analy...

Introduction: Amyotrophic Lateral Sclerosis is a group of sporadic or familial disorders, characterized by upper and lower motor neuron involvement, with variable progression. Areas covered: The authors present the role of exercise in counteracting muscle disuse, particularly on limb weakness, that might antagonize denervation. The persistence of inactivity can affect many systems and the patient can develop deconditioning, muscle joint tightness, which causes contractures and pain. The main area of the review is the evaluation of the studies done on ALS exercise rehabilitation protocols, this was done by the evaluation of outcome function and patient independence exerting a positive psychological impact on both patients and caregivers. A second target is underlying differences between endurance and resistance exercise protocols, which may throw light on the biological mechanism of skeletal muscle repair, functional performance, and metabolism. The authors present not only exercise trials but also molecular biomarkers that might help define changes induced by physical rehabilitation. Our findings might help to achieve the best rehabilitation program. A standardized rehabilitation protocol is important: the instructed patients may continue therapy at home or be followed by telemedicine. Expert opinion: This review evaluates exercise rehabilitation, a controversial issue, evidence is weak and non-conclusive but represents the art status.

Purpose. Motor skills can be learned in an explicit or an implicit manner. Explicit learning places high demands on working memory capacity, but engagement of working memory is largely circumvented when skills are learned implicitly. We propose that individuals with impaired movement dynamics may benefit from implicit learning methods when acquiring sportsrelated motor skills. Method. We discuss converging evidence that individuals with cerebral palsy and children born prematurely have compromised working memory capacity. This may in part explain the difficulties they encounter when learning motor and other skills. We also review tentative evidence that older people, whose movement dynamics deteriorate, can implicitly learn sports-related motor skills and that this results in more durable performance gains than explicit learning. Results. Individuals with altered movement dynamics and compromised working memory can benefit from implicit motor learning. Conclusion. We conclude with an appeal for more extensive evaluation of the merits of implicit motor learning in individuals with impaired movement dynamics.

This paper reports data from recent studies on integrative jaw–neck motor control in healthy subjects and disturbed jaw–neck behaviour in whiplash-associated disorders (WAD). The results show that neck function is an integral part of natural jaw behaviour, and that neck injury can impair jaw function and therefore disturb eating behaviour. We also show preliminary results from implementation of a new approach for rehabilitation of jaw–neck dysfunction and pain in WAD.

Eight subjects with carpal tunnel syndrome (CTS) (47.13 ± 7.83 years) and 8 matched controls (46.29 ± 7.27 years) manipulated a test object fitted with an accelerometer and force sensor, both before and after hand muscle fatigue. Grip force and object acceleration were recorded and used to calculate grip force control variables that included Grip Force Peak, Safety Margin, and Time to Grip Force Peak. Individuals with CTS exhibited a higher Safety Margin (p = .010) and longer Time to Peak of Grip Force (p = .012) than healthy controls during object manipulation. Once fatigued, both groups significantly decreased their grip force to perform the task (Grip Force Peak; p = .017 and Safety Margin; p < .001). Nevertheless, individuals with CTS maintained an unnecessarily high safety margin. Our results suggest that CTS can adversely affect how the central nervous system regulates grip force, which might aggravate the inflammatory process and exacerbate the symptoms of this disease.

Στην έρευνα αυτή εξετάσθηκε αν η επιδεξιότητα στο ποδόσφαιρο επηρεάζει την απόδοση και τη µάθηση µίας νέας δεξιότητας η οποία απαιτεί την διαρκή προσαρµογή της στάσης του σώµατος σε δυναµικές οπτικές πληροφορίες. Στην πειραµατική διαδικασία συµµετείχαν 10 έµπειροι ποδοσφαιριστές (ΟΠ) (ηλικία: 21.4±1.7, χρόνια προπόνησης: 8.6±3) και 10 φοιτητές φυσικής αγωγής ίδιας ηλικίας [Οµάδα Ελέγχου(ΟΕ), ηλικία: 20.4 ±0.8], από τους οποίους ζητήθηκε να σταθούν πάνω σε µία διπλή πλατφόρµα δύναµης (ERBE BALANCE SYSTEM) ενώ λάµβαναν οπτικές πληροφορίες σχετικά µε το διάνυσµα της δύναµης του κάθε ποδιού από την οθόνη ενός Η/Υ τοποθετηµένου µπροστά τους. Στόχος της δεξιότητας ήταν να µεταφέρουν το βάρος του σώµατος τους µεταξύ των δύο πλευρών µε τέτοιο τρόπο ώστε το διάνυσµα της δύναµης του κάθε ποδιού να παραµένει µέσα στα όρια που καθορίζονταν οπτικά από τις κυµατοειδείς τροχιές στην οθόνη του υπολογιστή. Η εξάσκηση περιελάµβανε 3 µπλοκ (1 λεπτό διάλειµµα) των 5 επαναλήψεων (10 δευτ διάλειµµα) και 1 µπλοκ των 5 επαναλήψεων 24 ώρες µετά (τεστ διατήρησης). Η µάθηση αξιολογήθηκε από το µέσο όρο (Μ0) και την τυπική απόκλιση (ΤΑ) του χρόνου κίνησης (ΧΚ) και του αριθµού λαθών (ΑΛ) τα οποία υπολογίστηκαν ανά 5 επαναλήψεις. Η στατιστική ανάλυση των αποτελεσµάτων έδειξε ότι οι ποδοσφαιριστές εκτέλεσαν τη δεξιότητα µε σηµαντικά πιο λίγα λάθη στην αριστερή πλευρά (p<0.05) είχαν πιο σταθερή εκτέλεση (p<0.05) και έµαθαν τη δεξιότητα πιο γρήγορα σε σχέση µε την ΟΕ (p<0.05). Συµπεραίνεται ότι η εξειδικευµένη προπόνηση ποδοσφαίρου ενισχύει τη σύζευξη µεταξύ αντίληψης και δράσης διευκολύνοντας έτσι τη µάθηση δεξιοτήτων οι οποίες απαιτούν την άµεση εφαρµογή οπτικών πληροφοριών σε κινητικές εντολές.