Physiotherapy based on problem-solving in upper limb function and neuroplasticity in chronic stroke patients: A case series

Rationale, aims, and objectives: Upper limb recovery is one of the main concerns of stroke neurorehabilitation. Neuroplasticity might underlie such recovery, particularly in the chronic phase. The purpose of this study was to assess the effect of physiotherapy based on problem-solving in recovering arm function in chronic stroke patients and explore its neuroplastic changes. Methods: A small sample research design with a n of 3 using a pre-post test design was carried out. Neuroplasticity and function were assessed by using functional magnetic resonance imaging (during motor imagery and performance), action research arm test, motor assessment scale, and Fugl-Meyer assessment scale, at 3 sequential time periods: baseline(m0before a 4-week period without physiotherapy), pre-treatment(m1), and post-treatment(m2). Minimal clinical important differences and a recovery score were assessed. Assessors were blinded to moment assignment. Patients(1) underwent physiotherapy sessions, 50minutes, 5days/week for 4weeks. Four control subjects served as a reference for functional magnetic resonance imaging changes. Results: All patients recovered more than 20% after intervention. Stroke patients had similar increased areas as healthy subjects during motor execution but not during imagination at baseline. Consequently, all patients increased activity in the contralateral precentral area after intervention. Conclusions: This study indicates that 4weeks of physiotherapy promoted the recovery of arm function and neuroplasticity in all chronic stroke patients. Future research is recommended to determine the efficacy of this therapy.info:eu-repo/semantics/publishedVersio

Median nerve stimulation induced motor learning in healthy adults: A study of timing of stimulation and type of learning

Median nerve stimulation (MNS) has been shown to change brain metaplasticity over the somatosensory networks, based on a bottom-up mechanism and may improve motor learning. This exploratory study aimed to test the effects of MNS on implicit and explicit motor learning as measured by the serial reaction time task (SRTT) using a double-blind, sham-controlled, randomized trial, in which participants were allocated to one of three groups: (a) online active MNS during acquisition, (b) offline active MNS during early consolidation and (c) sham MNS. SRTT was performed at baseline, during the training phase (acquisition period), and 30min after training. We assessed the effects of MNS on explicit and implicit motor learning at the end of the training/acquisition period and at retest. The group receiving online MNS (during acquisition) showed a significantly higher learning index for the explicit sequences compared to the offline group (MNS during early consolidation) and the sham group. The offline group also showed a higher learning index as compared to sham. Additionally, participants receiving online MNS recalled the explicit sentence significantly more than the offline MNS and sham groups. MNS effects on motor learning have a specific effect on type of learning (explicit vs. implicit) and are dependent on timing of stimulation (during acquisition vs. early consolidation). More research is needed to understand and optimize the effects of peripheral electrical stimulation on motor learning. Taken together, our results show that MNS, especially when applied during the acquisition phase, is a promising tool to modulate motor leaning.This work has been supported by a grant from Labuschagne Foundation to Spaulding Rehabilitation Hospital

Does Observation of Postural Imbalance Induce a Postural Reaction?

Import JabRef | WosArea Life Sciences and Biomedicine - Other TopicsInternational audienceBackground: Several studies bring evidence that action observation elicits contagious responses during social interactions. However automatic imitative tendencies are generally inhibited and it remains unclear in which conditions mere action observation triggers motor behaviours. In this study, we addressed the question of contagious postural responses when observing human imbalance. Methodology/Principal Findings: We recorded participants' body sway while they observed a fixation cross (control condition), an upright point-light display of a gymnast balancing on a rope, and the same point-light display presented upside down. Our results showed that, when the upright stimulus was displayed prior to the inverted one, centre of pressure area and antero-posterior path length were significantly greater in the upright condition compared to the control and upside down conditions. Conclusions/Significance: These results demonstrate a contagious postural reaction suggesting a partial inefficiency of inhibitory processes. Further, kinematic information was sufficient to trigger this reaction. The difference recorded between the upright and upside down conditions indicates that the contagion effect was dependent on the integration of gravity constraints by body kinematics. Interestingly, the postural response was sensitive to habituation, and seemed to disappear when the observer was previously shown an inverted display. The motor contagion recorded here is consistent with previous work showing vegetative output during observation of an effortful movement and could indicate that lower level control facilitates contagion effects

Obesity Impact on the Attentional Cost for Controlling Posture

International audienceBACKGROUND: This study investigated the effects of obesity on attentional resources allocated to postural control in seating and unipedal standing. METHODS: Ten non obese adults (BMI = 22.4±1.3, age = 42.4±15.1) and 10 obese adult patients (BMI = 35.2±2.8, age = 46.2±19.6) maintained postural stability on a force platform in two postural tasks (seated and unipedal). The two postural tasks were performed (1) alone and (2) in a dual-task paradigm in combination with an auditory reaction time task (RT). Performing the RT task together with the postural one was supposed to require some attentional resources that allowed estimating the attentional cost of postural control. 4 trials were performed in each condition for a total of 16 trials. FINDINGS: (1) Whereas seated non obese and obese patients exhibited similar centre of foot pressure oscillations (CoP), in the unipedal stance only obese patients strongly increased their CoP sway in comparison to controls. (2) Whatever the postural task, the additional RT task did not affect postural stability. (3) Seated, RT did not differ between the two groups. (4) RT strongly increased between the two postural conditions in the obese patients only, suggesting that body schema and the use of internal models was altered with obesity. INTERPRETATION: Obese patients needed more attentional resources to control postural stability during unipedal stance than non obese participants. This was not the case in a more simple posture such as seating. To reduce the risk of fall as indicated by the critical values of CoP displacement, obese patients must dedicate a strong large part of their attentional resources to postural control, to the detriment of non-postural events. Obese patients were not able to easily perform multitasking as healthy adults do, reflecting weakened psycho-motor abilities

Aging Affects the Mental Rotation of Left and Right Hands

BACKGROUND:Normal aging significantly influences motor and cognitive performance. Little is known about age-related changes in action simulation. Here, we investigated the influence of aging on implicit motor imagery. METHODOLOGY/PRINCIPAL FINDINGS:Twenty young (mean age: 23.9+/-2.8 years) and nineteen elderly (mean age: 78.3+/-4.5 years) subjects, all right-handed, were required to determine the laterality of hands presented in various positions. To do so, they mentally rotated their hands to match them with the hand-stimuli. We showed that: (1) elderly subjects were affected in their ability to implicitly simulate movements of the upper limbs, especially those requiring the largest amplitude of displacement and/or with strong biomechanical constraints; (2) this decline was greater for movements of the non-dominant arm than of the dominant arm. CONCLUSIONS/SIGNIFICANCE:These results extend recent findings showing age-related alterations of the explicit side of motor imagery. They suggest that a general decline in action simulation occurs with normal aging, in particular for the non-dominant side of the body

The influence of early aging on eye movements during motor simulation

Movement based interventions such as imagery and action observation are used increasingly to support physical rehabilitation of adults during early aging. The efficacy of these more covert approaches is based on an intuitively appealing assumption that movement execution, imagery and observation share neural substrate; alteration of one influences directly the function of the other two. Using eye movement metrics this paper reports findings that question the congruency of the three conditions. The data reveal that simulating movement through imagery and action observation may offer older adults movement practice conditions that are not constrained by the age-related decline observed in physical conditions. In addition, the findings provide support for action observation as a more effective technique for movement reproduction in comparison to imagery. This concern for imagery was also seen in the less congruent temporal relationship in movement time between imagery and movement execution suggesting imagery inaccuracy in early aging

Motor neuroplasticity: A MEG-fMRI study of motor imagery and execution in healthy ageing

Age-related decline in motor function is associated with over-activation of the sensorimotor circuitry. Using a multimodal MEG-fMRI paradigm, we investigated whether this neural over-recruitment in old age would be related to changes in movement-related beta desynchronization (MRBD), a correlate of the inhibitory neurotransmitter γ-aminobutyric acid (GABA), and whether it would characterize compensatory recruitment or a reduction in neural specialization (dedifferentiation). We used MEG to assess age-related changes in beta band oscillations in primary motor cortices, fMRI to localize age-related changes in brain activity, and the Finger Configuration Task to measure task performance during overt and covert motor processing: motor execution (ME) and motor imagery (MI). The results are threefold: first, showing age-related neuroplasticity during ME of older adults, compared to young adults, as evidenced by increased MRBD in motor cortices and over-recruitment of sensorimotor areas; second, showing similar age-related neuroplastic changes during MI; and finally, showing signs of dedifferentiation during ME in older adults whose performance negatively correlated with connectivity to bilateral primary motor cortex. Together, these findings demonstrate that elevated MRBD levels, reflecting greater GABAergic inhibitory activity, and over-activation of the sensorimotor network during ME may not be compensatory, but rather might reflect an age-related decline of the quality of the underlying neural signal

Age and gender differences in motor imagery

Few studies have explored the effects of ageing and gender in the dimensions of motor imagery (MI) such as vividness (vivid images and sensations of mental movements) and timing (the duration of an imagined movement). This study aims 1) to investigate the effect of age and gender effect in vividness and timing capabilities on MI, and 2) to examine the relationship between these two dimensions of MI

Cognition motrice et vieillissement (aspects fondamentaux et cliniques)

L étude des représentations du mouvement via des paradigmes basés sur l imagination ou l observation d actions constitue un moyen unique d accéder au contenu cognitif - comme la planification ou la programmation - du mouvement, en s affranchissant des informations sensorielles et motrices liées à son exécution réelle. Dans cette thèse, nous nous sommes intéressés au vieillissement des capacités de représentation - ou de simulation mentale selon Marc Jeannerod - du mouvement. Dans la première étude, nous avons plus spécifiquement exploré l évolution avec l âge du contenu non conscient - en lien avec la programmation - de la simulation mentale. A l aide d une tâche où les sujets devaient déterminer la latéralité de mains gauches et droites présentées dans différentes orientations, nous avons montré que les personnes âgées avaient des difficultés à simuler implicitement des mouvements du membre supérieur, et ce d autant plus que ces mouvements étaient contraignants au niveau biomécanique. Nous avons également mis en évidence que les représentations des mouvements du bras non-dominant était plus affectées que celles concernant le bras dominant. Dans la deuxième étude, nous nous sommes plus particulièrement intéressés aux représentations conceptuelles du mouvement, en rapport avec la planification de l action. Les participants devaient replacer dans l ordre des images représentant les différentes actions nécessaires pour se relever du sol. Là encore, nous avons montré que les sujets âgés avaient plus de difficultés que les jeunes à simuler mentalement une séquence motrice complexe. Enfin, dans une dernière étude, nous avons exploré l impact d une pratique d observation du mouvement, complémentaire à une pratique physique, sur l apprentissage / réapprentissage du relevé du sol chez des personnes âgées à risque de chute. Le nombre de personnes capables de se relever a augmenté significativement à l issue du programme d entraînement dans le groupe ayant suivi cette approche. Cependant, cette amélioration de la performance ne s est pas révélée plus importante que dans un groupe contrôle ayant suivi un entraînement physique seul. Les deux premières études ont donc montré que les processus de simulation mentale du mouvement sont altérés avec l âge, notamment en ce qui concerne les actions complexes. Ces résultats soulignent le rôle des composantes centrales de l action dans le déclin des performances motrices associé au vieillissement. La dernière étude n a pas révélé d impact significatif d une pratique d observation complémentaire à une pratique physique, dans l acquisition d une séquence motrice complexe. La pratique mentale - basée sur l imagerie motrice ou l observation - devrait se restreindre à des mouvements relativement simples avec des populations âgées.The study of movement representations through experimental paradigms based on action imagination or action observation is interesting to access to the cognitive content - like planning and programming - of an action, without being perturbed by the sensory and motor information associated with the actual execution. In this thesis, we were interested in studying the aging of movement representations - or mental simulation of movements (Jeannerod, 2001). In the first study, we have more specifically explored the age-related changes of the non conscious content - related to action programming - of the mental simulation. By means of a task where the subjects had to judge the laterality of left and right hands presented in different orientations, we have shown that elderly people were impaired in implicitly simulating upper-limb movements, particularly movements requiring strong biomechanical constraints. We have also revealed that the movement representations of the non-dominant arm were more affected by aging than those of the dominant arm. In the second study, we were more particularly interested in the conceptual representations of the movement, those in relation with action planning. The participants had to put in order images representing the different actions necessary to perform to rise from the floor. Here too, we have shown that the elderly subjects had more difficulties than their younger counterparts in mentally simulating this complex motor sequence. Finally, in the last study, we have investigated the impact of a mental practice based on action observation, complementary to a physical practice, on the learning / relearning of the rising from the floor , in elderly people at risk of falling. The percent of people able to rise has significantly increased at the end of the training program in the group which has followed this method. However, this increase in performance was not significantly more important than in a control group which has only followed a physical training. Thus, the first two studies have shown that the processes of the mental simulation of movement are impaired with advancing age, especially when complex actions have to be simulated. These results highlight the role of the central components of action in the age-related decline of motor performances. The last study has not revealed a significant impact of an observational practice complementary to a physical practice in the acquisition of a complex motor sequence. The mental practice - based on motor imagery or observation - should be limited to relatively simple movements with elderly people.DIJON-BU Sciences Economie (212312102) / SudocSudocFranceF