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What is so ‘effortful’ about handwriting? Webb, A. Henderson, S.E. Stuart, K.M. Institute of Education London University. Background.
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What is so ‘effortful’ about handwriting? Webb, A. Henderson, S.E. Stuart, K.M. Institute of Education London University
Background • It has long been recognised that children with Developmental Coordination Disorder (DCD) may experience difficulties with handwriting (e.g. Henderson & Hall, 1982; Losse et al, 1991; Smits-Engelsmann & Van Galen, 1997). • It is one of the diagnostic criteria for DCD listed in the DSM IV (APA, 2000).
Background 2 • My own experience working with children with DCD is that those with poor handwriting also often experience difficulties with the content of what they write. • Thus, the focus of my PhD thesis is the relationship between the physical act of handwriting and the composition quality of handwritten work in this particular group.
Evidence • The first three studies of the thesis found a clear and consistent relationship between the ability to handwrite and written composition quality. • These studies compared written with oral performance on a narrative task in verbally able, literate children, with and without DCD. • Overall, 176 scripts were rated blind to gender, group (DCD vs TD), mode (written vs oral) and order of production (written/oral vs oral/written).
Findings Three main features characterised the handwritten stories of the children with DCD: • They produced less text than the controls. • They sustained writing for less time. • Their handwritten compositions were weaker in ‘the generation and development of ideas’.
Possible factors in compositional weakness The selection of verbally able, literate children reduced the possibility that low general ability or impairments of language or literacy could account for the compositional weakness. ‘Capacity theory’
Capacity theory • Cognitive capacity is limited and finite. Different cognitive processes compete for resources, particularly on dual-tasks, such as writing (Hayes & Flower, 1986; Kellogg 1995). • The automation of certain processes (e.g. handwriting) maximises the processing capacity for others (e.g. composing). • Where handwriting and spelling still make undue demands of conscious control, essential cognitive resources are diverted away from the higher order processes of writing (McCutcheon, 1998; Torrance & Galbraith, 2007).
Aims of this study • In order to establish whether capacity theory could explain the weak composition of poor hand-writers with DCD, the demands of handwriting and spelling needed to be tested. • To this end, two experiments were designed to identify and then to measure the motor and orthographic demands of writing.
Rationale • Earlier research has examined handwriting behaviours as indicators of ‘mental workload’ (Rosenblum et al, 2003; Luria & Rosenblum, 2010, 2011). • As written composition can be conceptualised as ‘mental workload’ it is hypothesised that writing tasks of differing levels of demand would yield evidence of different handwriting characteristics. • It would also follow that any negative impact of this kind would be exaggerated in children with DCD.
Experiment 1: Method Participants 20 poorly coordinated boys (mean age 11.2 years; range 9.10-14.2) were selected from mainstream schools on the basis that they were considered to be bright, verbally fluent and read well, but had ‘poor’ handwriting. 15 met the inclusion criteria and agreed to participate. 15 controls matched for age, ability and literacy were chosen on the basis of good motor coordination and no handwriting problems.
Method 2 Testing All were tested on the following standardised measures: • WISC-R UK – short form (Wechsler, 1992) • WIAT II – word reading and spelling (Wechsler, …) • Movement ABC-2 (Henderson, Sugden & Barnett, 2007) • DASH (Barnett et al, 2007).
Tasks • Children were given a two-sentence introduction for a story to copy. The time taken was recorded. • They were next asked to continue the story in their own words for ten minutes. An electronic marker was placed after the same period of time which they had taken for the copying task. • Comparisons could then be made between the three tasks: • Copying • Freewriting 1 (FW1 = equal time ) • Freewriting 2 (FW2 = up to ten minutes).
Procedures • Tasks were performed on A4 paper affixed to a WACOM Intuos 4 digitiser tablet with a WACOM Intuos Cinteq sensitive inkpen. • The tablet was connected to a laptop computer on to which was installed the software for analysis.
ComPET software • The Computerized Penmanship Evaluation Tool (ComPET) developed by Rosenblum and colleagues at Haifa University was used to provide data on objective spatial, temporal and pressure measures (Rosenblum, Parush & Weiss, 2003a).
Experimental measures Certain specific measures were chosen to indicate handwriting demand based on the literature: • Total time on task (Smits-Engelsman et al, 2001) • Total time on paper (Luria & Rosenblum, 2011) • Total time in air (Luria & Rosenblum, 2011) • Velocity (Chang & Yu, 2010) • Pen pressure (Luria & Rosenblum, 2010) • Stroke variability (Parush et al, 1995a)
Results • Comparisons were made first between the copying task and the first free-writing task (FW1). These were of equal time duration. • Further comparisons were made between the first sample of free-writing (FW1) and the remaining free-writing task time to ten minutes (FW2). • ANOVAs were conducted with one between-subject factor (group: DCD or control) and with one within-subject factor (task: copying or FW1; FW1 or FW2).
1. Total time: Copying (and FW1) An independent t test showed there was a significant difference between groups in copying time (t = 3.902, p = .001): the DCD children took more time than controls.
2. Time spent ‘in air’:Copying vs FW1 • There was a significant main effect of group (F (1,24) = 4.445, p = .046) and of task (F (1,24) = 4.185, p = .050) but no group x task interaction: DCD spent longer ‘in air’ than the controls and both groups spent longer ‘in air’ for FW1 than when copying.
3.Time spent ‘on paper’:Copying vs FW1 • There was a significant main effect of group (F (1,24) = 5.003, p = .035) and of task (F (1,24) = 16.9, p = .000) and a significant group x task interaction (F (1,24) = 4.744, p = .039): DCD spent longer ‘on paper’ than controls and both spent longer ’on paper’ for copying than for FW1 but this was greater for the DCD group.
4. Velocity: Copying vs FW1 • There were no significant main effects of group or task and no group x task interaction. The DCD children wrote with equal velocity to the controls on both the copying and the short free-writing task.
5. Pen pressure: Copying vs FW1 There was a significant main effect of group (F (1,24) = 5.414, p = .029) but no main effect of task and no group x task interaction: The DCD children wrote with more pen pressure than the controls in both tasks. For pen pressure variability there was also a significant main effect of group (F (1,24) = 16.637, p = .000): the DCD children showed greater variability than the controls did.
6. Stroke efficiency:Copying vs FW1 • There were no significant main effects of group or task on stroke length, width or height. • However, there was a significant group x task interaction on stroke length (F (1,24) = 8.05. p = .009) and width (F (1,24) = 6.236, p = .02) : when transferring from copying to free-writing the DCD groups’ strokes increased in length and width.
Summary:Copying vs FW1 • DCD took longer for copying than controls. • DCD spent longer ‘on paper’ than controls. • Both groups spent longer time ‘0n paper’ for copying than for FW1, though the difference was greater for the DCD. • DCD spent longer ‘in air’ than controls on both tasks. • There was no group difference in velocity of writing. • DCD exerted more pressure than controls for both tasks and showed greater variability. • There was no group difference in stroke efficiency on copying, but in FW1 the DCD strokes increased in length and width.
Number of words: FW2 • An independent t-test showed that the controls wrote significantly more than the DCD group.
1-3. Time on task • There were no significant differences overall between FW1 and FW2 on time spent ‘0n paper’ or ‘in air’.
4. Velocity: FW1 vs FW2 • There was no significant main effect of group but there was of task (F (1,24) = 8.421, p = .000). There was no significant group x task interaction: velocity increased for both groups as they wrote more.
4. Velocity standard deviation There was a significant main effect of task (F (1,24) = 27.523, p = .008) and a significant group x task interaction (F (1,24) = 4.245, p = .050: variability increased for the DCD group as they wrote more.
5. Pen pressure: FW1 vs FW2 There was a significant main effect of group (F (1,24) = 6.239, p = .020) and of task (F (1,24) = 8.579, p = .000) and a significant group x task interaction (F (1,24) = 7.010, p = .014): the pen pressure exerted by the DCD group increased as they wrote for longer but it decreased for the controls.
6. Stroke efficiency • There were no significant differences between FW1 and FW2 on stroke efficiency.
Summary:FW1 vs FW2 • DCD produced less text overall than controls. • There were no group or task differences on time spent ‘on paper’ or ‘in air’ or in stroke efficiency. • There was no group difference on velocity but DCD showed greater variability. • As DCD wrote for longer their pen pressure increased. • As controls wrote for longer their pen pressure decreased. Question: If the DCD group could write as fast on the page as the controls why did they produce less text?
Conclusion • There is evidence on paper that supports an argument that handwriting is more demanding for children with DCD: - produced less text in all tasks, - exerted greater pressure overall, - showed greater variability, - strokes were less efficient when FW than when copying. 2. There is visual evidence that their ‘in air’ movement is less efficient (excess motor activity). • Controls seem able to make adjustments to their motor execution when task demands increase (e.g. by reducing pen pressure). • As the generation and development of ideas requires processing thatcannot be automated, it might easily be compromised where handwriting demanded the type of effort in evidence here.
For the future… • Software needs to be refined to measure and analyse the in-air traces more acutely. • The effect on motor execution of handwriting with different orthographic demand needs to be examined. • Handwritten execution to be compared with typed execution on similar tasks.
