Motor Imagery In Patients Research Articles

Beyond body image: what body schema and motor imagery can tell us about the way patients with anorexia nervosa experience their body.

Recent evidence suggests that the body image disturbance often observed in patients with anorexia nervosa also extends to the body schema. According to the embodiment approach, the body schema is not only involved in motor execution, but also in tasks that only require a mental simulation of a movement such as motor imagery, mental rotation of bodies, and visuospatial perspective-taking. The aim of the present study was to assess the ability of patients with anorexia to mentally simulate movements. The sample included 52 patients with acute anorexia and 62 healthy controls. All participants completed three tests of explicit motor imagery, a mental rotation test and a test of visuospatial perspective-taking. Patients with anorexia nervosa, with respect to controls, reported greater difficulties in imagining movements according to a first-person perspective, lower accuracy in motor imagery, selective impairment in the mental rotation of human figures, and reduced ability in assuming a different egocentric visuospatial perspective. These results are indicative of a specific alteration in motor imagery in patients with anorexia nervosa. Interestingly, patients' difficulties appear to be limited to those tasks which specifically rely on the body schema, while patients and controls performed similarly in the 3D objects mental rotation task.

Graded motor imagery modifies movement pain, cortical excitability and sensorimotor function in complex regional pain syndrome.

Patients with complex regional pain syndrome suffer from chronic neuropathic pain and also show a decrease in sensorimotor performance associated with characteristic central and peripheral neural system parameters. In the brain imaging domain, these comprise altered functional sensorimotor representation for the affected hand side. With regard to neurophysiology, a decrease in intracortical inhibition for the sensorimotor cortex contralateral to the affected hand has been repetitively verified, which might be related to increased primary somatosensory cortex functional activation for the affected limb. Rare longitudinal intervention studies in randomized controlled trials have demonstrated that a decrease in primary somatosensory cortex functional MRI activation coincided with pain relief and recovery in sensorimotor performance. By applying a randomized wait-list control crossover study design, we tested possible associations of clinical, imaging and neurophysiology parameters in 21 patients with complex regional pain syndrome in the chronic stage (>6 months). In more detail, we applied graded motor imagery over 6 weeks to relieve movement pain of the affected upper limb. First, baseline parameters were tested between the affected and the non-affected upper limb side and age-matched healthy controls. Second, longitudinal changes in clinical and testing parameters were associated with neurophysiological and imaging parameters. During baseline short intracortical inhibition, as assessed with transcranial magnetic stimulation, was decreased only for hand muscles of the affected hand side. During movement of the affected limb, primary somatosensory cortex functional MRI activation was increased. Hand representation area size for somatosensory stimulation in functional MRI was smaller on the affected side with longer disease duration. Graded motor imagery intervention but not waiting, resulted in a decrease of movement pain. An increase of somatosensory hand representation size over graded motor imagery intervention was related to movement pain relief. Over graded motor imagery intervention, pathological parameters like the increased primary somatosensory cortex activation during fist movement or decreased short intracortical inhibition were modified in the same way as movement pain and hand performance improved. No such changes were observed during the waiting period. Overall, we demonstrated characteristic changes in clinical, behaviour and neuropathology parameters applying graded motor imagery in patients with upper limb complex regional pain syndrome, which casts light on the effects of graded motor imagery intervention on biomarkers for chronic neuropathic pain.

Study of the effects of kinesthetic motor imagery in patients with heart failure.

The aim was to investigate the acute effect of kinesthetic motor imagery of the 2-minute walk test on hemodynamic and cardiopulmonary variables in patients with heart failure. Twenty participants were recruited for the analysis of these variables before and after the execution and imagination of the 2-minute walk test, with the number of laps executed and imagined being recorded. The main results observed showed that (1) there was no difference in the number of laps executed and imagined (p=0.41), indicating that the participants actually imagined the test and (2) the motor imagery of the 2-minute walk test immediately increased (p<0.001) the heart and respiratory rates. The motor imagery seems to have acute effects on the cardiopulmonary anticipatory responses of a patient with heart failure.

Kinesthetic illusion induced by visual stimulation influences sensorimotor event-related desynchronization in stroke patients with severe upper-limb paralysis: A pilot study

Repetition of motor imagery improves the motor function of patients with stroke. However, patients who develop severe upper-limb paralysis after chronic stroke often have an impaired ability to induce motor imagery. We have developed a method to passively induce kinesthetic perception using visual stimulation (kinesthetic illusion induced by visual stimulation [KINVIS]). This pilot study further investigated the effectiveness of KINVIS in improving the induction of kinesthetic motor imagery in patients with severe upper-limb paralysis after stroke. Twenty participants (11 with right hemiplegia and 9 with left hemiplegia; mean time from onset [±standard deviation], 67.0±57.2 months) with severe upper-limb paralysis who could not extend their paretic fingers were included in this study. The ability to induce motor imagery was evaluated using the event-related desynchronization (ERD) recorded during motor imagery before and after the application of KINVIS for 20 min. The alpha- and beta-band ERDs around the premotor, primary sensorimotor, and posterior parietal cortices of the affected and unaffected hemispheres were evaluated during kinesthetic motor imagery of finger extension and before and after the intervention. Beta-band ERD recorded from the affected hemisphere around the sensorimotor area showed a significant increase after the intervention, while the other ERDs remained unchanged. In patients with chronic stroke who were unable to extend their paretic fingers for a prolonged period of time, the application of KINVIS, which evokes kinesthetic perception, improved their ability to induce motor imagery. Our findings suggest that although KINVIS is a passive intervention, its short-term application can induce changes related to the motor output system.

Five days of rTMS associated with motor imagery can decrease durably central neuropathic pain: Results from a cohort of 47 patients

Neuropathic pain is frequent and often drug resistant, with an important impact on quality of life and function recovery. The aim of this study was to assess the efficacy of high frequency rTMS on motor cortex associated with motor imagery in patients with neuropathic pain. Between December 2014 and April 2017, 47 patients with central neuropathic pain were included. We studied clinical parameters (age, gender, pathology, pain duration and pain location) as well as cortical excitability. Before the treatment, a DN4 score and a BPI score were realized. Those two scores were repeated 48 hours after the treatment, at the beginning and at the end of 5 days of treatment, and during the follow up (at M1, M3 and M6). The treatment consisted in daily rTMS session, during five days, associated with motor imagery and mirror therapy. The primary outcome was a decreasing of the most intense pain of two points, defining responders. Thirty-four men and 13 women, 56,5 years old mean, with neuropathic pain from 6.6 years on average, principally secondary to stroke ( n = 24) were included. Thirty percent of patients were responders at 48 hours, M1 and M3, and this diminution of pain was significant (all P < 0.05). There was a significant association between responders at 48 hours and responders at M1 and M3, as well as between pain duration and non-responders at M3 (< 0.03). This study shows that high frequency TMS on the motor cortex associated with motor imagery can decrease neuropathic pain, as it is describes in literature, but durably with an effect until 3 months in our study. Furthermore, it may exist a link between responders at 48 hours and responders in the long term.

Decoding of Ankle Flexion and Extension from Cortical Current Sources Estimated from Non-invasive Brain Activity Recording Methods.

The classification of ankle movements from non-invasive brain recordings can be applied to a brain-computer interface (BCI) to control exoskeletons, prosthesis, and functional electrical stimulators for the benefit of patients with walking impairments. In this research, ankle flexion and extension tasks at two force levels in both legs, were classified from cortical current sources estimated by a hierarchical variational Bayesian method, using electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) recordings. The hierarchical prior for the current source estimation from EEG was obtained from activated brain areas and their intensities from an fMRI group (second-level) analysis. The fMRI group analysis was performed on regions of interest defined over the primary motor cortex, the supplementary motor area, and the somatosensory area, which are well-known to contribute to movement control. A sparse logistic regression method was applied for a nine-class classification (eight active tasks and a resting control task) obtaining a mean accuracy of 65.64% for time series of current sources, estimated from the EEG and the fMRI signals using a variational Bayesian method, and a mean accuracy of 22.19% for the classification of the pre-processed of EEG sensor signals, with a chance level of 11.11%. The higher classification accuracy of current sources, when compared to EEG classification accuracy, was attributed to the high number of sources and the different signal patterns obtained in the same vertex for different motor tasks. Since the inverse filter estimation for current sources can be done offline with the present method, the present method is applicable to real-time BCIs. Finally, due to the highly enhanced spatial distribution of current sources over the brain cortex, this method has the potential to identify activation patterns to design BCIs for the control of an affected limb in patients with stroke, or BCIs from motor imagery in patients with spinal cord injury.

Effects of mirror therapy on the reacquisition of motor imagery in patients with a hand orthopaedic injury

Background: On commencing occupational therapy (OT), some patients with hand orthopaedic injury complain of not knowing how to move an affected finger. Aim/Objective: We report a patient who did no...

Effects of Intermittent Theta Burst Stimulation on Manual Dexterity and Motor Imagery in Patients with Multiple Sclerosis: A Quasi-Experimental Controlled Study

BackgroundIntermittent theta burst stimulation (iTBS) is a repetitive transcranial magnetic stimulation (rTMS) protocol that influences cortical excitability and motor function recovery.ObjectivesThis study aimed to investigate the effects of iTBS on manual dexterity and hand motor imagery in multiple sclerosis (MS) patients.MethodsThirty-six MS patients were non-randomly assigned into sham (control) or iTBS groups. Then, iTBS was delivered to the primary motor cortex for ten days over two consecutive weeks. The patients’ manual dexterity was assessed using the nine-hole peg test (9HPT) and the Box and Block Test (BBT), while the hand motor imagery was assessed with the hand mental rotation task (HMRT).ResultsiTBS group showed a reduction in the time required to complete the 9HPT (mean difference = -3.05, P = 0.002), and an increase in the number of blocks transferred in one minute in the BBT (mean difference = 8.9, P = 0.001) when compared to the control group. Furthermore, there was no significant difference between the two groups in terms of the reaction time (P = 0.761) and response accuracy rate (P = 0.482) in the HMRT.ConclusionsWhen iTBS was applied over the primary motor cortex, it significantly improved manual dexterity, but had no significant effect on the hand motor imagery ability in MS patients.

Functional Preservation and Reorganization of Brain during Motor Imagery in Patients with Incomplete Spinal Cord Injury: A Pilot fMRI Study.

Motor imagery (MI) is a cognitive process involved in mentally rehearsing movement representations, and it has great potential for the rehabilitation of motor function in patients with spinal cord injuries. The aim of this study was to explore changes in the brain activation patterns in incomplete spinal cord injury (ISCI) patients during motor execution (ME) and MI tasks, and to thereby explore whether MI shares similar motor-related networks with ME in ISCI patients. Seventeen right-handed ISCI patients with impaired motor function of their right ankles and 17 age- and gender-matched healthy controls were enrolled in this study. The activation patterns of the ISCI subjects and those of the healthy subjects were compared, both during mental dorsi-plantar flexion of the right ankle (the MI task) and the actual movement of the joint (the ME task). The patients and the healthy controls shared similar activation patterns during the MI or ME tasks. The activation patterns of the MI task between the patients and the healthy controls were more similar than those of the ME task. These findings indicate that the MI network is more functionally preserved than the ME network in ISCI patients. In addition, increased activation in the motor-related regions during ME task, and decreased activation in the parietal regions during both ME and MI tasks, were identified in the ISCI patients compared to the healthy controls, indicating a functional reorganization of these regions after ISCI. The functional preservation and reorganization of the MI network in the ISCI patients suggests a potential role for MI training in motor rehabilitation.

Interaction of BCI with the underlying neurological conditions in patients: pros and cons.

Interaction of BCI with the underlying neurological conditions in patients: pros and cons.

Activity of right premotor-parietal regions dependent upon imagined force level: an fMRI study.

In this study, we utilized functional magnetic resonance imaging (fMRI) to measure blood oxygenation level-dependent (BOLD) signals. This allowed us to evaluate the relationship between brain activity and imagined force level. Subjects performed motor imagery of repetitive right hand grasping with three different levels of contractile force; 10%, 30%, and 60% of their maximum voluntary contraction (MVC). We observed a common activation among each condition in the following brain regions; the dorsolateral prefrontal cortex (DLPFC), ventrolateral prefrontal cortex (VLPFC), supplementary motor area (SMA), premotor area (PM), insula, and inferior parietal lobule (IPL). In addition, the BOLD signal changes were significantly larger at 60% MVC than at 10% MVC in the right PM, the right IPL, and the primary somatosensory cortex (SI). These findings indicate that during motor imagery right fronto-parietal activity increases as the imagined contractile force level is intensified. The present finding that the right brain activity during motor imagery is clearly altered depending on the imagined force level suggests that it may be possible to decode intended force level during the motor imagery of patients or healthy subjects.

Correction: Comparison of EEG-Features and Classification Methods for Motor Imagery in Patients with Disorders of Consciousness

Correction: Comparison of EEG-Features and Classification Methods for Motor Imagery in Patients with Disorders of Consciousness

P1038: Evaluation of H reflex excitability during motor imagery in patients with the restless legs syndrome and healthy individuals

P1038: Evaluation of H reflex excitability during motor imagery in patients with the restless legs syndrome and healthy individuals

Effect of Motor Imagery in Children with Unilateral Cerebral Palsy: fMRI Study

BackgroundMotor imagery is considered as a promising therapeutic tool for rehabilitation of motor planning problems in patients with cerebral palsy. However motor planning problems may lead to poor motor imagery ability.AimThe aim of this functional magnetic resonance imaging study was to examine and compare brain activation following motor imagery tasks in patients with hemiplegic cerebral palsy with left or right early brain lesions. We tested also the influence of the side of imagined hand movement.MethodTwenty patients with clinical hemiplegic cerebral palsy (sixteen males, mean age 12 years and 10 months, aged 6 years 10 months to 20 years 10 months) participated in this study. Using block design, brain activations following motor imagery of a simple opening-closing hand movement performed by either the paretic or nonparetic hand was examined.ResultsDuring motor imagery tasks, patients with early right brain damages activated bilateral fronto-parietal network that comprise most of the nodes of the network well described in healthy subjects. Inversely, in patients with left early brain lesion brain activation following motor imagery tasks was reduced, compared to patients with right brain lesions. We found also a weak influence of the side of imagined hand movement.ConclusionDecreased activations following motor imagery in patients with right unilateral cerebral palsy highlight the dominance of the left hemisphere during motor imagery tasks. This study gives neuronal substrate to propose motor imagery tasks in unilateral cerebral palsy rehabilitation at least for patients with right brain lesions.

Comparison of EEG-Features and Classification Methods for Motor Imagery in Patients with Disorders of Consciousness

Current research aims at identifying voluntary brain activation in patients who are behaviorally diagnosed as being unconscious, but are able to perform commands by modulating their brain activity patterns. This involves machine learning techniques and feature extraction methods such as applied in brain computer interfaces. In this study, we try to answer the question if features/classification methods which show advantages in healthy participants are also accurate when applied to data of patients with disorders of consciousness. A sample of healthy participants (N = 22), patients in a minimally conscious state (MCS; N = 5), and with unresponsive wakefulness syndrome (UWS; N = 9) was examined with a motor imagery task which involved imagery of moving both hands and an instruction to hold both hands firm. We extracted a set of 20 features from the electroencephalogram and used linear discriminant analysis, k-nearest neighbor classification, and support vector machines (SVM) as classification methods. In healthy participants, the best classification accuracies were seen with coherences (mean = .79; range = .53−.94) and power spectra (mean = .69; range = .40−.85). The coherence patterns in healthy participants did not match the expectation of central modulated -rhythm. Instead, coherence involved mainly frontal regions. In healthy participants, the best classification tool was SVM. Five patients had at least one feature-classifier outcome with p0.05 (none of which were coherence or power spectra), though none remained significant after false-discovery rate correction for multiple comparisons. The present work suggests the use of coherences in patients with disorders of consciousness because they show high reliability among healthy subjects and patient groups. However, feature extraction and classification is a challenging task in unresponsive patients because there is no ground truth to validate the results.

Imagined motor action and eye movements in schizophrenia

Visual exploration and planning of actions are reported to be abnormal in schizophrenia. Most of the studies monitoring eye movements in patients with schizophrenia have been performed under free-viewing condition. The present study was designed to assess whether mentally performing an action modulates the visuomotor behavior in patients with schizophrenia and in healthy controls. Visual scan paths were monitored in eighteen patients with schizophrenia and in eighteen healthy controls. Participants performed two tasks in which they were asked either to (1) look at a scene on a computer screen (free viewing), or (2) picture themselves making a sandwich in front of a computer screen (active viewing). The scenes contained both task-relevant and task-irrelevant objects. Temporal and spatial characteristics of scan paths were compared for each group and each task. The results indicate that patients with schizophrenia exhibited longer fixation durations, and fewer fixations, than healthy controls in the free viewing condition. The patients' visual exploration improved in the active viewing condition. However, patients looked less at task-relevant objects and looked more at distractors than controls in the active viewing condition in which they were asked to picture themselves making a sandwich in moving their eyes to task-relevant objects on an image. These results are consistent with the literature on deficits in motor imagery in patients with schizophrenia and it extends the impairment to visual exploration in an action imagery task.

Cued motor imagery in patients with multiple sclerosis

Motor imagery (MI) is a promising practice tool in neurorehabilitation. However, in patients with multiple sclerosis (MS), impairments in MI accuracy and temporal organization were found during clinical assessment, which may limit the benefits of MI practice. Therefore, we investigated whether the MI quality of MS patients could be optimized by means of external cueing. Fourteen patients with MS and 14 healthy control patients physically executed and visually imagined a goal-directed upper limb task in the presence and absence of added visual and auditory cues. MI quality was assessed by means of eye-movement registration. As main results, it was found that MS patients had significant higher eye-movement times than controls during both execution and imagery, and overestimated the to-be-imagined movement amplitude when no external information was provided during imagery. External cues, however, decreased patients' MI duration and increased the spatial accuracy of their imagined movements. In sum, our results indicate that MS patients imagine movements in a better way when they are provided with external cues during MI. These findings are important for developing rehabilitation strategies based on MI in patients with MS.

Effect of Motor Imagery in Patients with Parkinson Disease Using F-wave

Effect of Motor Imagery in Patients with Parkinson Disease Using F-wave

Motor imagery in patients with a right hemisphere stroke and unilateral neglect

Introduction: In the last decade new treatments based on mental imagery have been developed for patients with stroke. Whether this therapy works for patients with neglect is currently unclear.Objective: To investigate whether patients with a right hemisphere stoke complicated with unilateral neglect were less capable of performing motor imagery as compared to patients with a right hemisphere stroke without unilateral neglect.Methods: In a patient-control study, 20 patients with a right hemisphere stroke were included. Twelve patients were diagnosed on admission with neglect and eight without neglect. The ability to perform motor imagery was tested using mental rotation tasks, based on either a visual (CMIA ‘Hand Rotation’ test) or a verbal (Questionnaire d’Imagerie Mentale: Rotation des Mains) instruction. In both tasks subjects were instructed to generate a mental image of their hand.Results: Patients with neglect scored significantly less (p = 0.02) as compared to patients without neglect on the visual mental rotation task, but not on the mental rotation task with verbal instruction.Conclusion: Patients with a right-hemisphere stroke and neglect seem less capable of performing visual mental rotation tasks in comparison to patients with a stroke without neglect.

Modulation of Event-related Desynchronization duringMotor Imagery with Transcranial Direct Current Stimulationin a Patient with Severe Hemiparetic Stroke: A Case Report

Recently, surface electroencephalogram (EEG)-based brain-machine interfaces (BMI) have been used for people with disabilities. As a BMI signal source, event-related desynchronization of alpha-band EEG (8-13 Hz) during motor imagery (mu ERD), which is interpreted as desynchronized activities of the activated neurons, is commonly used. However, it is often difficult for patients with severe hemiparesis to produce mu ERD of sufficient strength to activate BMI. Therefore, whether it is possible to modulate mu ERD during motor imagery with anodal transcranial direct-current stimulation (tDCS) was assessed in a severe left hemiparetic stroke patient. EEG was recorded over the primary motor cortex (M1), and mu ERD during finger flexion imagery was measured before and after a 5-day course of tDCS applied to M1. The ERD recorded over the affected M1 increased significantly after tDCS intervention. Anodal tDCS may increase motor cortex excitability and potentiate ERD during motor imagery in patients with severe hemiparetic stroke.