Planning and control in a manual collision avoidance task by children with hemiparesis

Upper Limb Motor Planning in Individuals with Cerebral Palsy Aged between 3 and 21 Years Old: A Systematic Review

Individuals with cerebral palsy have difficulties performing activities of daily living. Beyond motor execution impairments, they exhibit motor planning deficits contributing to their difficulties. The objective of this review is to synthesize the behavioral evidence of motor planning deficits during an upper limb motor task in children, adolescents and young adults with cerebral palsy aged between 3 and 21 years. Methods: The inclusion criteria were: (1) including individuals with cerebral palsy from 3 to 21 years old; (2) assessing upper limb motor planning. Six databases were screened. The quality assessment of the studies was performed. Results: Forty-six studies and 686 participants were included. Five articles have been identified as very high quality, 12 as high, 20 as moderate, six as low, three as very low. Force planning studies reported a deficit for the more affected hand but adequate performances for the less affected hand. Object-manipulation studies reported hand posture planning deficits irrespectively of the hand assessed. Conclusions: Motor planning deficits has been shown in the more affected hand for force scaling, while the results for other variables showed overall deficits. Hence, variables affected by motor planning deficits in both hands should be considered in children with cerebral palsy to optimize intervention.

Impaired anticipatory vision and visuomotor coordination affects action planning and execution in children with hemiplegic cerebral palsy

BACKGROUND

Action-planning and execution deficits in children with hemiplegic cerebral palsy (HCP) are potentially due to deficits in the integration of sensory information, such as vision, with motor output.

AIMS

To determine differences in anticipatory visual patterns in children with HCP compared to typically developing (TD) children, and to assess visuomotor coordination in children with HCP.

METHODS AND PROCEDURES

We included 13 children with HCP (Age = 6.8 + 2.9 yrs) and 15 TD children (Age = 5.8 + 1.1 yrs). The experimental task used in this study is a valid action-planning task, which consisted of initially reaching and grasping an object placed at a fixed position, followed by placing the object in a random target position. Visual patterns were recorded using a head-mounted eye-tracker system and arm movements were recorded using motion capture (120 Hz).

OUTCOMES AND RESULTS

Children with HCP had delayed anticipatory gaze time and longer latency than TD children during the planning and execution phases. Children with HCP also had a higher frequency of gaze shifts, longer reaction times (RT) and movement times (MT) than TD children.

CONCLUSIONS AND IMPLICATIONS

Children with HCP may have deficits in anticipatory vision, which potentially affected planning and executing a goal-directed action. Therapeutic interventions focusing on improving visuomotor coordination may improve the motor performance in children with HCP.

Motor imagery difficulties in children with Cerebral Palsy: A specific or general deficit?

AIM

The aim of this study was to examine the specificity of motor imagery (MI) difficulties in children with CP.

METHOD

Performance of 22 children with CP was compared to a gender and age matched control group. MI ability was measured with the Hand Laterality Judgment (HLJ) task, examining specifically the direction of rotation (DOR) effect, and the Praxis Imagery Questionnaire (PIQ).

RESULTS

In the back view condition of the HLJ task both groups used MI, as evidenced by longer response times for lateral compared with medial rotational angles. In the palm view condition children with CP did not show an effect of DOR, unlike controls. Error scores did not differ between groups. Both groups performed well on the PIQ, with no significant difference between them in response pattern.

CONCLUSION AND IMPLICATION

The present study suggests that children with CP show deficits on tasks that trigger implicit use of MI, whereas explicit MI ability was relatively preserved, as assessed using the PIQ. These results suggest that employing more explicit methods of MI training may well be more suitable for children with CP in rehabilitation of motor function.

Upper limb activity in children with unilateral spastic cerebral palsy: the role of vision in movement strategies

This article reviews the capacity of children with unilateral spastic cerebral palsy (USCP) to (re)organize the available degrees of freedom and to use visual information in interceptive actions during motion with either the impaired or the less-impaired hand. Atypical reaching movements, such as increased trunk movement or slower wrist velocity, are considered adaptive coordination patterns that are the result of a change in the constraints. It is argued that manipulation of the task context facilitates children with USCP to enhance performance. For example, when reducing the time available to intercept a ball, the children are found to exceed their usual maximum walking speed and to increase range of motion of the elbow. In addition, the children appear to rely on a visual information strategy similar to typically developing children ('bearing angle'), although more variability is observed when using the impaired arm. The implications for interventions are, it should be recognized, that these children adapt to the impairment by reorganizing the movement system and that this process can be influenced by changing the task context. Attention should be paid to the importance of using correct visual cues for initiation and guidance of interceptive actions, which may be provoked by using external visual triggers.

Gaze behaviour during interception in children with spastic unilateral cerebral palsy

Anticipatory gaze behaviour during interceptive movements was investigated in children with Spastic Unilateral Cerebral Palsy (SUCP), and related to the side of the intracerebral lesion. Five children with lesions of the right hemisphere (RHL) and five children with lesions of the left hemisphere (LHL) had to walk towards and intercept a ball that moved perpendicular to the walking path. Interception accuracy and gaze patterns were measured in a no-occlusion and occlusion condition, in which the ball was occluded from view for half of its trajectory. There was a clear support for a relationship between gaze behaviour and success in interception performance, with some evidence for the presence of anticipatory gaze behaviour. There were also differences in gaze behaviour between children with RHL and children with LHL that might be related to planning, but these did not affect interception accuracy. It is concluded that gaze behaviour during interceptive movements is anticipatory, and at least partly dependent on the lesional side.

Visual guidance of interceptive actions in children with spastic unilateral cerebral palsy is influenced by the side of the lesion

PURPOSE

To determine the type of visual information used by children with spastic unilateral cerebral palsy (SUCP) in order to intercept a ball and to verify whether this information was dependent on the side of the lesion. More specifically, it was examined whether the interception was controlled on the basis of a time or a distance strategy, initiating the catch when the ball is at a fixed time interval or at a fixed distance from the point of interception.

METHODS

Three groups of children were included. Children with either a left sided (LHL) or a right sided lesion (RHL) and children without a lesion [typically developing (TD)] intercepted a ball from a conveyor belt. In order to intercept the ball successfully they had to walk and to reach for the ball at the interception point 4 m away.

RESULTS

Children with LHL had a longer decision time and started their reach movement earlier. In 56% of the children with LHL a distance strategy was observed, while in the TD and the children with RHL predominantly a time strategy was found.

CONCLUSIONS

The side of the lesion influences the visual information used to initiate interceptive actions.

Motor planning in congenital hemiplegia

PURPOSE

Cerebral Palsy (CP) is a broad definition of a neurological condition in which disorders in movement execution and postural control limit the performance of activities of daily living. In this paper, we first review studies on motor planning in hemiplegic CP. Second, preliminary data of a recent study on eye-hand coordination in participants with hemiplegic CP are presented. Here, the potential role of vision for online and prospective control of action was examined.

METHOD

Review and presentation of preliminary data of an eye- and hand movement registration experiment in hemiplegic CP.

RESULTS

Deficits in motor planning in hemiplegic CP contribute to limitations of activities of daily living. In the second part, exemplary plots of eye-hand coordination are presented for the affected and unaffected hand in one participant with hemiplegic CP, and for the preferred hand in controls, both as an illustration of the research methodology and to give an impression of the observed gaze patterns.

CONCLUSION

Research on CP should not solely focus on low-level aspects of action execution, but also take into account the more high-level aspects of motor control, such as planning. Possible deviations therein may be sought in altered gaze patterns as illustrated in the paper.

Visual information for action planning in left and right congenital hemiparesis

Converging evidence suggests that compromised motor abilities in hemiparetic cerebral palsy are not solely due to impairments in motor execution, but are also related to deficits in action planning. The present study had two aims. First, we compared grip planning in a sequential task between participants with left-sided (n=12) or right-sided (n=10) congenital hemiparesis. Second, we studied the use of visual information for grip planning by having participants grasp a rod embedded in a 'rod-and-frame' illusion. The results showed that especially participants with right hemiparesis revealed planning problems as most of them did not switch between different grip types at all or they switched in an inconsistent manner. In contrast, the majority of participants with left hemiparesis showed consistent planning of the first part of the task. Second, the results indicated that visual information provided by the illusion had an effect on grip planning in participants that used a consistent planning strategy, suggesting that the use of visual information in action planning was not affected in these participants. The results are discussed in relation to hemispheric differences in motor planning and visuo-motor integration in congenital hemiparesis.

Eye-hand coordination during manual object transport with the affected and less affected hand in adolescents with hemiparetic cerebral palsy

In the present study we investigated eye-hand coordination in adolescents with hemiparetic cerebral palsy (CP) and neurologically healthy controls. Using an object prehension and transport task, we addressed two hypotheses, motivated by the question whether early brain damage and the ensuing limitations of motor activity lead to general and/or effector-specific effects in visuomotor control of manual actions. We hypothesized that individuals with hemiparetic CP would more closely visually monitor actions with their affected hand, compared to both their less affected hand and to control participants without a sensorimotor impairment. A second, more speculative hypothesis was that, in relation to previously established deficits in prospective action control in individuals with hemiparetic CP, gaze patterns might be less anticipatory in general, also during actions performed with the less affected hand. Analysis of the gaze and hand movement data revealed the increased visual monitoring of participants with CP when using their affected hand at the beginning as well as during object transport. In contrast, no general deficit in anticipatory gaze control in the participants with hemiparetic CP could be observed. Collectively, these findings are the first to directly show that individuals with hemiparetic CP adapt eye-hand coordination to the specific constraints of the moving limb, presumably to compensate for sensorimotor deficits.

Solving a mental rotation task in congenital hemiparesis: motor imagery versus visual imagery

A recent study showed that motor imagery was compromised after right congenital hemiparesis. In that study, posture of the displayed stimuli and the actual posture of the hand making the response were incongruent. Ample evidence exists that such an incongruency may negatively influence laterality judgements in a mental rotation task. In the present study, three participant groups (controls, left hemiparesis, right hemiparesis [all n=11]) performed a mental rotation task in which posture of the displayed hand and the responding hand were congruent. A small amount of errors were made and linear relations between reaction times and rotation angles of the stimuli were found for all groups, suggesting intact motor imagery. However, reaction times for the participants with hemiparesis were consistently slower compared to controls and no asymmetry in responding between the affected and less-affected hand was found, suggesting a visual imagery strategy. Collectively, these results suggest that the ability to mentally rotate stimuli is still intact in right hemiparesis. The results are discussed in relation to two strategies that may have been used to solve the task: visual imagery and motor imagery.