Visual perception and upper limb function in children with developmental coordination disorder

Abstract

Background: Poor upper limb coordination is one of the most common problems experienced by children with Developmental Coordination Disorder (DCD). Researchers have hypothesised that visual perception deficits exist in children with DCD and are partly responsible for the motor coordination problems demonstrated in this population. Previous studies analysing global visual perception in children with DCD are limited, with the presence of global visual perception deficits unable to be confirmed. The contribution of visual perception to types of upper limb function in children with DCD has not been measured, making it considerably difficult to accurately guide treatment of upper limb coordination deficits. Purpose: The aim of this study is to determine if global visual perception deficits exist in children with DCD, and the relative contribution of visual perception towards types of upper limb function. Methods: Thirty-two children aged 6-12 years, 17 with DCD and 15 typical developing (TD) children were included in the study. Visual perception was assessed using the Motor- Free Visual Perception Test-3 (MVPT). Upper limb function was assessed in terms of speed of everyday unimanual tasks (Jebsen-Taylor Test of Hand Function: JTTHF-Objects and JTTHF-Handwriting); handwriting speed and accuracy (Evaluation Tool of Children's Handwriting (ETCH)) and manual dexterity (Movement Assessment Battery for Children, 2nd edition (MABC2)). Results: Children with DCD demonstrated significantly poorer scores on global visual perception (MVPT) than TD children (p = 0.033). Visual perception was most predictive of performance on manual dexterity tasks (MABC2-MD, accounting for 24% of the variation (p = 0.003)) and unimanual upper limb speed-based tasks (JTTHF-Objects, accounting for 21% of the variation for the dominant hand (p = 0.005), and 20% for the non-dominant hand (p = 0.008)). Visual perception also predicted handwriting performance, contributing to 19% of the variation in legibility of letters (p = 0.009) and 10% of the variation in legibility of words (p = 0.045). There was a non-significant trend between visual perception and legibility of numbers (p = 0.084). Visual perception was only related to handwriting speed for one subtest, uppercase alphabet writing (p = 0.032), accounting for 11% of this variability. There was no relationship between visual perception and handwriting speed (p > 0.25) for other ETCH subtests, including lowercase alphabet writing (p = 0.660), numeric writing (p = 0.25), near-point copying (p = 0.421), far-point copying (p = 0.953) and sentence composition p = 0.543). Visual perception was not related to aiming and catching (p = 0.084) and balance (p = 0.123) components of the MABC-2. Age and gender did not contribute to the significance of the model for any of the tests. Conclusion(s): Overall, these findings reveal that visual perception makes a large contribution to upper limb function for children with DCD, especially for dexterity and speed-based upper limb tasks involving hand trajectories and grasp. Implications: These findings highlight the importance of providing formal visual perception assessment and treatment for children with DCD.L721142832015-12-22 <br />