Positive Technology Journal

Facilitation of motor imagery through movement-related cueing.

Brain Res. 2009 Apr 27;

Authors: Heremans E, Helsen WF, De Poel HJ, Alaerts K, Meyns P, Feys P

In the past few years, the use of motor imagery as an adjunct to other forms of training has been studied extensively. However, very little attention has been paid to how imagery could be used to greatest effect. It is well known that the provision of external cues has a beneficial effect on motor skill acquisition and performance during physical practice. Since physical execution and mental imagery share several common mechanisms, we hypothesized that motor imagery might be affected by external cues in a similar way. To examine this, we compared the motor imagery performance of three groups of 15 healthy participants who either physically performed or imagined performing a goal-directed cyclical wrist movement in the presence or the absence of visual and/or auditory external cues. As outcome measures, the participants' imagery vividness scores and eye movements were measured during all conditions. We found that visual movement-related cues improved the spatial accuracy of the participants' eye movements during imagery, while auditory cues specifically enhanced their temporal accuracy. Furthermore, both types of cues significantly improved the participants' imagery vividness. These findings indicate that subjects may imagine a movement in a better way when provided with external movement-related stimuli, which may possibly be useful with regard to the efficiency of mental practice in (clinical) training protocols.

Development of hierarchical structures for actions and motor imagery: a constructivist view from synthetic neuro-robotics study.

Psychol Res. 2009 Apr 8;

Authors: Nishimoto R, Tani J

The current paper shows a neuro-robotics experiment on developmental learning of goal-directed actions. The robot was trained to predict visuo-proprioceptive flow of achieving a set of goal-directed behaviors through iterative tutor training processes. The learning was conducted by employing a dynamic neural network model which is characterized by their multiple time-scale dynamics. The experimental results showed that functional hierarchical structures emerge through stages of developments where behavior primitives are generated in earlier stages and their sequences of achieving goals appear in later stages. It was also observed that motor imagery is generated in earlier stages compared to actual behaviors. Our claim that manipulatable inner representation should emerge through the sensory-motor interactions is corresponded to Piaget's constructivist view.

Effects of mental imagery styles on shoulder and hip rotations during preparation of pirouettes.

J Mot Behav. 2008 Jul;40(4):281-90

Authors: Golomer E, Bouillette A, Mertz C, Keller J

To analyze individual behavior in spatial navigation especially for pirouette preparations (complete whole-body rotations), the authors studied horizontal shoulder-hip interactions under 2 constraints: postural (right and left supporting legs [SL]) and spatial (clockwise [CW] and counterclockwise [CCW]). They performed kinematic analysis at the start and end of the shoulder-hip horizontal rotations (run-up) with regard to imagery of motor actions. On the basis of the Vividness of Movement Imagery Questionnaire, they classified 8 female expert ballet dancers and 7 untrained female participants according to their movement imagery style (kinesthetic and visual). At the run-up's end, the shoulders initiated the turn independently of SL but differently depending on training: CW for dancers and CCW for untrained participants (their commonly used direction). Kinesthetic and mixed imagery styles prevailed in dancers, whereas simply a mixed style appeared among untrained participants. Thus, dance training enhances the imagery of kinesthetic sensation and influences the choice of spatial direction, facilitating the body-space interaction.

Using mental practice in stroke rehabilitation: a framework.

Clin Rehabil. 2008 Jul;22(7):579-91

Authors: Braun S, Kleynen M, Schols J, Schack T, Beurskens A, Wade D

Introduction: Motor imagery and mental practice are getting increased attention in neurological rehabilitation. Several different mental practice intervention protocols have been used in studies on its effect on recovery in stroke rehabilitation. The content of the intervention protocols itself is rarely discussed or questioned.Objective: To give a practical framework of how mental practice could be integrated into therapy, drawing on available evidence and theory. The aim of the treatment programme described is to enhance both the patient's physical performance and their empowerment and self-determination.The framework: Based on evidence from sports rehabilitation and our own experiences the framework will eventually be evaluated in a randomized controlled trial. Five steps are described to teach and upgrade the patient's imagery technique: (1) assess mental capacity to learn imagery technique; (2) establish the nature of mental practice; (3) teach imagery technique; (4) embed and monitor imagery technique; (5) develop self-generated treatments. The description is not, however, a recipe that should be followed precisely. It leaves enough room to tailor the mental practice intervention to the specific individual possibilities, skills and needs of the patient in accordance with evidence-based practice.Discussion: Different aspects of the described protocol are discussed and compared with experiences from sports and evidence available in rehabilitation.

Neural activation in cognitive motor processes: comparing motor imagery and observation of gymnastic movements.

Exp Brain Res. 2008 Apr 19;

Authors: Munzert J, Zentgraf K, Stark R, Vaitl D

Kinesthetic Imagery and Tool-Specific Modulation of Corticospinal Representations in Expert Tennis Players.

Cereb Cortex. 2008 Feb 21;

Authors: Fourkas AD, Bonavolontà V, Avenanti A, Aglioti SM

Specific physical or mental practice may induce short- and long-term neuroplastic changes in the motor system and cause tools to become part of one's own body representation. Athletes who use tools as part of their practice may be an excellent model for assessing the neural correlates of possible bodily representation changes that are specific to extensive practice. We used single-pulse transcranial magnetic stimulation to measure corticospinal excitability in forearm and hand muscles of expert tennis players and novices although they mentally practiced a tennis forehand, table tennis forehand, and a golf drive. The muscles of expert tennis players showed increased corticospinal facilitation during motor imagery of tennis but not golf or table tennis. Novices, although athletes, were not modulated across sports. Subjective reports indicated that only in the tennis imagery condition did experts differ from novices in the ability to form proprioceptive images and to consider the tool as an extension of the hand. Neurophysiological and subjective data converge to suggest a key role of long-term experience in modulating sensorimotor body representations during mental simulation of sports.

Clinical Assessment of Motor Imagery After Stroke.

Neurorehabil Neural Repair. 2008 Mar 6;

Authors: Malouin F, Richards C, Durand A, Doyon J

OBJECTIVE: The aim of this study was to investigate: (1) the effects of a stroke on motor imagery vividness as measured by the Kinesthetic and Visual Imagery Questionnaire (KVIQ-20); (2) the influence of the lesion side; and (3) the symmetry of motor imagery. METHODS: Thirty-two persons who had sustained a stroke, in the right (n = 19) or left (n = 13) cerebral hemisphere, and 32 age-matched healthy persons participated. The KVIQ-20 assesses on a 5-point ordinal scale the clarity of the image (visual scale) and the intensity of the sensations (kinesthetic scale) that the subjects are able to imagine from the first-person perspective. RESULTS: In both groups, the visual scores were higher (P = .0001) than the kinesthetic scores and there was no group difference. Likewise, visual scores remained higher than kinesthetic scores irrespective of the lesion side. The visual scores poststroke were higher (P = .001) when imagining upper limb movements on the unaffected side than those on the affected side. When focusing on the lower limb only, however, the kinesthetic scores were higher (P = .001) when imagining movements of the unaffected compared to those on the affected side. CONCLUSIONS: The vividness of motor imagery poststroke remains similar to that of age-matched healthy persons and is not affected by the side of the lesion. However, after stroke motor imagery is not symmetrical and motor imagery vividness is better when imagining movements on the unaffected than on the affected side, indicating an overestimation possibly related to a hemispheric imbalance or a recalibration of motor imagery perception.

Effect of mental imagery on the development of skilled motor actions.

Percept Mot Skills. 2007 Dec;105(3 Pt 1):803-26

Authors: Fontani G, Migliorini S, Benocci R, Facchini A, Casini M, Corradeschi F

To test the effect of imagery in the training of skilled movements, an experiment was designed in which athletes learned a new motor action and trained themselves for a month either by overt action or by mental imagery of the action. The experiment was carried out with 30 male karateka (M age = 35 yr., SD = 8.7; M years of practice = 6, SD = 3) instructed to perform an action (Ura-Shuto-Uchi) that they had not previously learned. The athletes were divided into three groups: Untrained (10 subjects who did not perform any training), Action Trained (10 subjects who performed Ura-Shuto-Uchi training daily for 16 minutes), and Mental Imagery (10 subjects who performed mental imagery training of Ura-Shuto-Uchi daily for 16 minutes). The subjects were tested five times, once every 7 days. During each test, they performed a series of 60 motor action trials. In Tests 1, 3, and 5, they also performed a series of 60 mental imagery trials. During the trials, an electroencephalogram (EEG), electromyography (EMG), muscle strength and power, and other physiological parameters were recorded. The results differed by group. Untrained subjects did not show significant effects. In the Action Trained group, training had an effect on reactivity and movement speed, with a reduction of EMG activation and reaction times. Moreover, muscle strength, power, and work increased significantly. The Mental Imagery group showed the same effects on muscle strength, power, and work, but changes in reactivity were not observed. In the Mental Imagery group, the study of Movement Related Brain Macropotentials indicated a progressive modification of the profile of the waves from Test 1 to Test 5 during imagery, showing significant variations of the amplitude of the waves related to the premotor and motor execution periods. Results show that motor imagery can influence muscular abilities such as strength and power and can modify Movement Related Brain Macropotentials, the profile of which potentially could be used to verify the effectiveness of motor imagery training.

Effect of mental imagery on the development of skilled motor actions.

Percept Mot Skills. 2007 Dec;105(3 Pt 1):803-26

Authors: Fontani G, Migliorini S, Benocci R, Facchini A, Casini M, Corradeschi F

To test the effect of imagery in the training of skilled movements, an experiment was designed in which athletes learned a new motor action and trained themselves for a month either by overt action or by mental imagery of the action. The experiment was carried out with 30 male karateka (M age = 35 yr., SD = 8.7; M years of practice = 6, SD = 3) instructed to perform an action (Ura-Shuto-Uchi) that they had not previously learned. The athletes were divided into three groups: Untrained (10 subjects who did not perform any training), Action Trained (10 subjects who performed Ura-Shuto-Uchi training daily for 16 minutes), and Mental Imagery (10 subjects who performed mental imagery training of Ura-Shuto-Uchi daily for 16 minutes). The subjects were tested five times, once every 7 days. During each test, they performed a series of 60 motor action trials. In Tests 1, 3, and 5, they also performed a series of 60 mental imagery trials. During the trials, an electroencephalogram (EEG), electromyography (EMG), muscle strength and power, and other physiological parameters were recorded. The results differed by group. Untrained subjects did not show significant effects. In the Action Trained group, training had an effect on reactivity and movement speed, with a reduction of EMG activation and reaction times. Moreover, muscle strength, power, and work increased significantly. The Mental Imagery group showed the same effects on muscle strength, power, and work, but changes in reactivity were not observed. In the Mental Imagery group, the study of Movement Related Brain Macropotentials indicated a progressive modification of the profile of the waves from Test 1 to Test 5 during imagery, showing significant variations of the amplitude of the waves related to the premotor and motor execution periods. Results show that motor imagery can influence muscular abilities such as strength and power and can modify Movement Related Brain Macropotentials, the profile of which potentially could be used to verify the effectiveness of motor imagery training.

The suppressive influence of SMA on M1 in motor imagery revealed by fMRI and dynamic causal modeling.

Neuroimage. 2007 Dec 8;

Authors: Kasess CH, Windischberger C, Cunnington R, Lanzenberger R, Pezawas L, Moser E

Although motor imagery is widely used for motor learning in rehabilitation and sports training, the underlying mechanisms are still poorly understood. Based on fMRI data sets acquired with very high temporal resolution (300 ms) under motor execution and imagery conditions, we utilized Dynamic Causal Modeling (DCM) to determine effective connectivity measures between supplementary motor area (SMA) and primary motor cortex (M1). A set of 28 models was tested in a Bayesian framework and the by-far best-performing model revealed a strong suppressive influence of the motor imagery condition on the forward connection between SMA and M1. Our results clearly indicate that the lack of activation in M1 during motor imagery is caused by suppression from the SMA. These results highlight the importance of the SMA not only for the preparation and execution of intended movements, but also for suppressing movements that are represented in the motor system but not to be performed.

Mental rotation of congenitally absent hands.

J Int Neuropsychol Soc. 2008 Jan;14(1):81-9

Authors: Funk M, Brugger P

The emergence of motor imagery in children.

J Exp Child Psychol. 2007 Nov 28;

Authors: Molina M, Tijus C, Jouen F

Quasi-movements: A novel motor-cognitive phenomenon.

Neuropsychologia. 2007 Oct 22;

Authors: Nikulin VV, Hohlefeld FU, Jacobs AM, Curio G

We introduce quasi-movements and define them as volitional movements which are minimized by the subject to such an extent that finally they become undetectable by objective measures. They are intended as overt movements, but the absence of the measurable motor responses and the subjective experience make quasi-movements similar to motor imagery. We used the amplitude dynamics of electroencephalographic alpha oscillations as a marker of the regional involvement of cortical areas in three experimental tasks: movement execution, kinesthetic motor imagery, and quasi-movements. All three conditions were associated with a significant suppression of alpha oscillations over the sensorimotor hand area of the contralateral hemisphere. This suppression was strongest for executed movements, and stronger for quasi-movements than for motor imagery. The topography of alpha suppression was similar in all three conditions. Proprioceptive sensations related to quasi-movements contribute to the assumption that the "sense of movement" can originate from central efferent processes. Quasi-movements are also congruent with the postulated continuity between motor imagery and movement preparation/execution. We also show that in healthy subjects quasi-movements can be effectively used in brain-computer interface research leading to a significantly smaller classification error ( approximately 47% of relative decrease) in comparison to the errors obtained with conventionally used motor imagery strategies.

High loads induce differences between actual and imagined movement duration.

Exp Brain Res. 2007 Nov 1;

Authors: Slifkin AB

Actual and imagined action may be governed by common information and neural processes. This hypothesis has found strong support from a range of chronometric studies showing that it takes the same amount of time to actually move and to imagine moving. However, exceptions have been observed when actual and imagined movements were made under conditions of inertial loading: sometimes the equivalency of actual and imagined movement durations (MDs) has been preserved, and other times it has been disrupted. The purpose of the current study was to test the hypothesis that the appearance and magnitude of actual-imagined MD differences in those studies was dependent on the level of load relative to the maximum loading capacity of the involved effector system [the maximum voluntary load (MVL)]. The experiment required 12 young, healthy humans to actually produce, and to imagine producing, single degree of freedom index finger movements under a range of loads (0, 5, 10, 20, 40, and 80% MVL). As predicted, statistically significant actual-imagined MD differences were absent at lower loads (0-20% MVL), but differences appeared and increased in magnitude with further increases in %MVL (40 and 80% MVL). That pattern of results may relate to the common, everyday experience individuals have in interacting with loads. Participants are likely to have extensive experience interacting with very low loads, but not high loads. It follows that the control of low inertial loads should be governed by complete central representations of action, while representations should be less complete for high loads. A consequence may be increases in the uncertainty of predicting motor output with increases in load. Compensation for the increased uncertainty may appear as increases in the MD values selected during both the preparation and imagery of action-according to a speed-uncertainty trade-off. Then, during actual action, MD may be reduced if movement-related feedback indicates that a faster movement would succeed.

Effects of movement imagery and electromyography-triggered feedback on arm hand function in stroke patients in the subacute phase.

Clin Rehabil. 2007 Jul;21(7):587-94

Authors: Hemmen B, Seelen HA

OBJECTIVE: To investigate the effects of movement imagery-assisted electromyography (EMG)-triggered feedback (focused on paretic wrist dorsiflexors) on the arm-hand function of stroke patients. DESIGN: Single-blinded, longitudinal, multicentre randomized controlled trial. Measurements were performed (on average) 54 days post stroke (baseline), three months later (post training) and at 12 months post baseline. SETTING: Two rehabilitation centres. SUBJECTS: Twenty-seven patients with a first-ever, ischaemic, subacute stroke. INTERVENTIONS: A reference group received conventional electrostimulation, while the experimental group received arm-hand function training based on EMG-triggered feedback combined with movement imagery. Both groups were trained for three months, 5 days/week, 30 minutes/day, in addition to their therapy as usual. MAIN MEASURES: Arm-hand function was evaluated using the upper extremity-related part of the Brunnstrom Fugl-Meyer test and the Action Research Arm test. RESULTS: During training, Brunnstrom Fugl-Meyer scores improved 8.7 points and Action Research Arm scores by 19.4 points (P < 0.0001) in both groups relative to baseline results, rising to 13.3 and 28.4 points respectively at one year follow-up (P < 0.0001). No between-group differences were found at any time. CONCLUSIONS: EMG-triggered feedback stimulation did not lead to more arm-hand function improvement relative to conventional electrostimulation. However, in contrast to many clinical reports, a significant improvement was still observed in both groups nine months after treatment ceased.

Movement imagery increases pain in people with neuropathic pain following complete thoracic spinal cord injury.

Pain. 2007 Oct 15;

Authors: Gustin SM, Wrigley PJ, Gandevia SC, Middleton JW, Henderson LA, Siddall PJ

Spinal cord injury (SCI) results in deafferentation and the onset of neuropathic pain in a substantial proportion of people. Based on evidence suggesting motor cortex activation results in attenuation of neuropathic pain, we sought to determine whether neuropathic SCI pain could be modified by imagined movements of the foot. Fifteen subjects with a complete thoracic SCI (7 with below-level neuropathic pain and 8 without pain) were instructed in the use of movement imagery. Movement imagery was practiced three times daily for 7days. On the eighth day, subjects performed the movement imagery in the laboratory and recorded pain ratings during the period of imagined movement. Six out of 7 subjects with neuropathic pain reported an increase in pain during imagined movements from 2.9+/-0.7 during baseline to 5.0+/-1.0 during movement imagery (p<0.01). In SCI subjects without neuropathic pain, movement imagery evoked an increase in non-painful sensation intensity from a baseline of 1.9+/-0.7 to 4.8+/-1.3 during the movement imagery (p<0.01). Two subjects without a history of pain or non-painful phantom sensations had onset of dysesthesia while performing imagined movements. This study reports exacerbation of pain in response to imagined movements and it contrasts with reports of reduction pain in people with peripheral neuropathic pain. The potential mechanisms underlying this sensory enhancement with movement imagery are discussed.

Preservation of motor programs in paraplegics as demonstrated by attempted and imagined foot movements.

Neuroimage. 2007 Aug 23;

Authors: Hotz-Boendermaker S, Funk M, Summers P, Brugger P, Hepp-Reymond MC, Curt A, Kollias SS

Execution and imagination of movement activate distinct neural circuits, partially overlapping in premotor and parietal areas, basal ganglia and cerebellum. Can long-term deafferented/deefferented patients still differentiate attempted from imagined movements? The attempted execution and motor imagery network of foot movements have been investigated in nine chronic complete spinal cord-injured (SCI) patients using fMRI. Thorough behavioral assessment showed that these patients were able to differentiate between attempted execution and motor imagery. Supporting the outcome of the behavioral assessment, fMRI disclosed specific patterns of activation for movement attempt and for motor imagery. Compared with motor execution data of healthy controls, movement attempt in SCI patients revealed reduced primary motor cortex activation at the group level, although activation was found in all single subjects with a high variability. Further comparisons with healthy subjects revealed that during attempt and motor imagery, SCI patients show enhanced activation and recruitment of additional regions in the parietal lobe and cerebellum that are important in sensorimotor integration. These findings reflect central plastic changes due to altered input and output and suggest that SCI patients may require additional cognitive resources to perform these tasks that may be one and the same phenomenon, or two versions of the same phenomenon, with quantitative differences between the two. Nevertheless, the retained integrity of movement attempt and motor imagery networks in SCI patients demonstrates that chronic paraplegics can still dispose of the full motor programs for foot movements and that therefore, attempted and imagined movements should be integrated in rehabilitative strategies.

Visuo-motor learning with combination of different rates of motor imagery and physical practice.

Exp Brain Res. 2007 Sep 12;

Authors: Allami N, Paulignan Y, Brovelli A, Boussaoud D

Sports psychology suggests that mental rehearsal facilitates physical practice in athletes and clinical rehabilitation attempts to use mental rehearsal to restore motor function in hemiplegic patients. Our aim was to examine whether mental rehearsal is equivalent to physical learning, and to determine the optimal proportions of real execution and rehearsal. Subjects were asked to grasp an object and insert it into an adapted slot. One group (G0) practiced the task only by physical execution (240 trials); three groups imagined performing the task in different rates of trials (25%, G25; 50%, G50; 75%, G75), and physically executed movements for the remaining trials; a fourth, control group imagined a visual rotation task in 75% of the trials and then performed the same motor task as the others groups. Movement time (MT) was compared for the first and last physical trials, together with other key trials, across groups. All groups learned, suggesting that mental rehearsal is equivalent to physical motor learning. More importantly, when subjects rehearsed the task for large numbers of trials (G50 and G75), the MT of the first executed trial was significantly shorter than the first executed trial in the physical group (G0), indicating that mental practice is better than no practice at all. Comparison of the first executed trial in G25, G50 and G75 with the corresponding trials in G0 (61, 121 and 181 trials), showed equivalence between mental and physical practice. At the end of training, the performance was much better with high rates of mental practice (G50/G75) compared to physical practice alone (G0), especially when the task was difficult. These findings confirm that mental rehearsal can be beneficial for motor learning and suggest that imagery might be used to supplement or partly replace physical practice in clinical rehabilitation.

Relationship between visual and motor imagery.

Percept Mot Skills. 2007 Jun;104(3 Pt 1):823-43

Authors: McAvinue LP, Robertson IH

The relationship between visual and motor imagery was investigated by administering a battery of visual and motor imagery measures to a sample of 101 men (n=49) and women (n=52), who ranged in age from 18 to 59 (M=34.5, SD= 12.6). A principal components analysis applied to the correlation matrix indicated four underlying components, which explained 62.9% of the variance. The components were named Implicit Visual Imagery Ability, Self-report of Visual and Motor Imagery, Implicit Motor Imagery Ability, and Explicit Motor Imagery Ability. These results suggested a dissociation between visual and motor imagery although visual and motor imagery were associated as self-reports and there were correlations among particular measures.

Internal and external imagery perspective measurement and use in imagining open and closed sports skills: an exploratory study.

Percept Mot Skills. 2007 Apr;104(2):387-404

Authors: Spittle M, Morris T

This study explored the measurement and use of internal and external imagery perspectives during imagery of open and closed sports skills. Participants (N=41; male=23; female=18), ages 14 to 28 (M = 19.4 yr.; SD = 3.1), who were recruited from undergraduate classes in human movement and physical education, and local sporting teams, completed the Imagery Use Questionnaire and then imagined performing eight common sports skills, four open skills and four closed skills, in a random order. Participants provided concurrent verbalisation during their imagery. Immediately after imagining each skill, participants completed a rating scale and retrospective verbalisation of imagery perspective use. Analysis indicated that the questionnaire gave a general imagery perspective preference but was not a strong predictor of imagery used on specific occasions. The three measures of imagery perspective were equivalent in imagining performing particular skills. Participants experienced more internal imagery than external imagery while imagining the eight sports skills, but there was no significant difference between perspective use on the open and closed skills.