Eye hand coordination in children with cerebral palsy

Abstract

Reaching to grasp an object of interest requires complex sensorimotor coordination involving eye, head, hand and trunk. While numerous studies have demonstrated deficits in each of these systems individually, little is known about how children with cerebral palsy (CP) coordinate multiple motor systems for functional tasks. Here we used kinematics, remote eye tracking and a trunk support device to examine the functional coupling of the eye, head and hand and the extent to which it was constrained by trunk postural control in 10 children with CP (6-16 years). Eye movements in children with CP were similar to typically developing (TD) peers, while hand movements were significantly slower. Postural support influenced initiation of hand movements in the youngest children (TD & CP) and execution of hand movements in children with CP differentially depending on diagnosis. Across all diagnostic categories, the most robust distinction between TD children and children with CP was in their ability to isolate eye, head and hand movements. Results of this study suggest that deficits in motor coordination for accurate reaching in children with CP may reflect coupled eye, head, and hand movements. We have previously suggested that coupled activation of effectors may be the default output for the CNS during early development.

Figures

Figure 1

Group means for frequency of saccadic intrusions in typically developing children (unfilled symbols and dashed lines) and children with cerebral palsy (filled symbols and solid lines) during control vs. hand only tasks. Means were collapsed across postural support conditions. Error bars, intersubject SE.

Figure 2

Group means for hand submovements (number of zero acceleration crossings) with three levels of postural support; no support (light shade), hip support (medium shade) and upper torso support (dark shade).Error bars, intersubject SE.

Figure 3

Group means (a) and diagnosis means (b) for hand peak velocity with three levels of postural support; no support (light shade), hip support (medium shade) and upper torso support (dark shade). Error bars, intersubject SE.

Figure 3

Group means (a) and diagnosis means (b) for hand peak velocity with three levels of postural support; no support (light shade), hip support (medium shade) and upper torso support (dark shade). Error bars, intersubject SE.