Motor imagery in children with unilateral cerebral palsy: a case-control study

Motor imagery ability in children and adolescents with cerebral palsy: a systematic review and evidence map

Background

Cerebral palsy (CP) refers to a group of permanent movement and posture disorders. Motor imagery (MI) therapy is known to provide potential benefits, but data on MI ability in children and adolescents with CP is lacking.

Objective

A systematic review was performed to explore MI abilities in children and adolescents with CP compared to typically developed (TD) subjects.

Methods

We searched on PubMed, Web of Science (WOS), EBSCO, Google Scholar, and PEDro including observational studies. Methodological quality was assessed with the modified Newcastle-Ottawa Scale and evidence map was created to synthesize the evidence qualitatively and quantitatively.

Results

Seven cross-sectional studies were selected, which included 174 patients with CP and 321 TD subjects. Three studies explored explicit MI, two MI-execution synchrony, and four implicit MI domains. Methodological quality ranged from 6 to 8 stars. Moderate evidence supported the absence of differences in vividness between the groups. As there was only limited evidence, establishing a clear direction for the results was not possible, especially for the capacity to generate MI, mental chronometry features, and MI-execution synchrony domains. Moderate evidence supported a lower efficiency in cases for hand recognition, derived from a lower accuracy rate, while reaction time remained similar between the two groups. Moderate evidence indicated that patients with CP and TD controls showed similar features on whole-body recognition.

Conclusion

Moderate evidence suggests that patients with CP present a reduced ability in hand recognition, which is not observed for whole-body recognition compared to healthy controls. Severe limitations concerning sample size calculations and validity of assessment tools clearly limits establishing a direction of results, especially for explicit MI and MI-Execution synchrony domains. Further research is needed to address these limitations to enhance our comprehension of MI abilities in children, which is crucial for prescribing suitable MI-based therapies in this child population.

Children with Cerebral Palsy can imagine actions like their normally developed peers

The present study aimed at assessing whether children with Cerebral Palsy (CP) can imagine object directed actions similarly to their normally developed peers. We asked children with CP (n = 12) and paired healthy controls (n = 12) to imagine in first person perspective eight daily actions, after observing them through videoclips presented on a computer screen. During motor imagery (MI) children were interrupted at a specific timepoint (e.g., at 2.5 s) from the start. Two frames extracted from the videoclips were then presented on the screen. One of the two depicted the correct timepoint at which the imagined action was interrupted, while the other represented an earlier or later timepoint. Children had to respond by pressing the key associated to the correct frame. Children also underwent VMIQ-2 questionnaire. Both groups performed similarly in the questionnaire and in the requested task, where they showed the same error rate. Errors mainly concerned the later frame, suggesting a similar strategy to solve the task in the two groups. The results support the view that children with CP can imagine actions similarly to their normally developed peers. This encourages the use of MI as a rehabilitative tool in children with motor impairment.

Motor imagery in congenital hemiplegia: Impairments are not universal

BACKGROUND

Motor imagery (MI) training may benefit children with congenital hemiplegia, but reports on MI ability are mixed. This study considered individual patterns of performance to better understand MI ability in children with hemiplegia.

METHOD

Twenty children with hemiplegia (7-13 years; 10 with right hemiplegia), completed a MI task, IQ estimate and functional tests. Children with hemiplegia scoring above chance on the MI task were compared to a group of age-matched peers. The performance patterns of those scoring below chance were considered individually.

RESULTS

Three children with right hemiplegia were excluded due to low IQ. Seven of 10 children with left hemiplegia and three of seven with right hemiplegia performed MI at an equivalent level to peers without hemiplegia. The seven children with hemiplegia who scored significantly below chance scored lower on functional tests, but differences here failed to reach an adjusted significance level. Four of the seven appeared engaged in MI, but performed very poorly. The remaining three had unique performance patterns explored in more detail.

CONCLUSION

Motor imagery deficits are not universally observed in children with congenital hemiplegia and individual performance should be examined before completing group analyses. Recommendations for exclusions and reporting in future studies are made.

Neuromotor examination in unilateral cerebral palsy: Bilateral impairments in different levels of motor integration

Unilateral cerebral palsy (UCP) usually results in damage to the unilateral pyramidal system. However, the clinical presentation of neuromotor deficits also suggests lesions to the extrapyramidal and cerebellar systems bilaterally. In this study, we developed and tested a behavioral neuromotor examination protocol assessing impairments at three levels of motor integration for children with UCP, also considering impairments of the non-paretic upper limb as well as the influences of the laterality of the lesion. We included 30 children with UCP (10.79 ± 2.61 years) and 60 healthy children (8.27 ± 1.57 years) in the study. All children were assessed on general cognitive ability and classified according to the manual ability classification system (MACS). Our neuromotor examination protocol incorporated specific tasks for each level of motor integration: pyramidal, extrapyramidal and cerebellar. Children with UCP and controls did not differ with respect to general cognitive abilities and sex but children with UCP were significantly older. Controls performed significantly better than children with UCP on neuromotor tasks at all levels of motor integration. Additionally, performance of the non-plegine hand in children with UCP was significantly inferior to controls. With the exception of fine motor skills (pyramidal level), children with right and left UCP did not differ. Our behavioral neuromotor examination was sensitive to reveal impairments at all three levels of motor integration bilaterally in children with UCP-although more subtle for the non-paretic limb.

Relationship between motor abilities and executive functions in patients after pediatric stroke

Patients after pediatric stroke typically experience varying extent of motor and cognitive impairments. During rehabilitation, these impairments are often treated as separate entities. While there is a notion claiming that motor and cognitive functions are interrelated to some degree in healthy children, a minimal amount of evidence exists regarding this issue in patients after pediatric stroke. The purpose of this study was to investigate the association between motor abilities and executive functions in patients after pediatric arterial ischemic stroke. Twenty-seven patients (6 - 23 years) diagnosed with pediatric arterial ischemic stroke in the chronic phase (≥ 2 years after diagnosis, diagnosed < 16 years) and 49 healthy controls (6 - 26 years) were included in this study. Participants completed six tasks from standardized neuropsychological tests assessing the dimensions of executive functions, namely working memory, inhibition, and shifting. Additionally, we assessed hand strength and upper limb performance with two tasks each. In the patient group, the association between upper limb performance and executive functions was stronger than between hand strength and executive functions. Our results point toward the idea of a close interrelation between upper limb performance and executive functions. Training more complex and cognitively engaging motor abilities involving upper limb performance rather than basic motor abilities such as hand strength during a rehabilitation program may have the power to foster executive function development and vice versa in patients after stroke.