Table 1.
Summary of studies on additional modalities of handwriting contributing to Parkinson's disease dysgraphia
| Reference | Participants | Handwriting task | Comparisons | Modalities | Conclusion |
|---|---|---|---|---|---|
| Poluha et al., 199842 | PD, n = 10 | Sequence “le” and “hell” | On vs. off | Upstroke duration; upstroke size | There was a significant reduction in upstroke duration during on state, whereas upstroke size did not change significantly |
| Tucha et al., 20069 | PD, n = 27; HC, n = 27 | Letter combination “ll”; off vs. on | PD vs. HC; off vs. on | Distance of writing trace, movement time, fluency, (NIV/NIA), maximum velocity, and acceleration | Compared with the HC group, patients who had PD had shorter writing trace, longer movement time, less fluency, and lower maximum velocity and acceleration; these parameters (except distance of writing trace) improved significantly with medication |
| Lange et al., 200643 | PD, n = 12; HC, n = 12 | “helles,” “grelles” | PD vs. HC | Movement distance, movement time, fluency (NIV/NIA) maximum velocity, and acceleration | Compared with the HC group, patients who had PD had shorter movement distance, longer movement time, less fluency, and lower maximum velocity and acceleration; these parameters (except movement distance) improved significantly with medication |
| Broderick et al. 200963 | PD, n = 20; EHC, n = 16; YHC, n = 16 | “^” shape with vertex angle of 40 degrees | EHC vs. PD; YHC vs. PD | Mean acceleration, peak acceleration, mean velocity, normalized jerk | In both age groups, compared with HCs, patients who had PD had significantly lower mean acceleration, peak acceleration, and mean velocity and higher normalized jerk |
| Rosenblum et al., 20137 | PD, n = 20; HC, n = 20 | Full name, address | PD vs. HC | Mean stroke duration (on paper and in air), stroke width, velocity, and pressure | Compared with the HC group, patients who had PD had significantly longer mean stroke duration, both on paper and in air (more pronounced in air); the PD group also had shorter width, lesser velocity, and applied less pressure on paper while writing |
| Yu et al., 201638 | PD, n = 12; ET, n = 13; HC, n = 21 | (1) Crosses, 50 mm2; (2) 20‐mm‐tall cursive “ill”; (3) single circle with 20‐mm diameter; (4) 10 overlapping circles | Mean velocity, progressive vertical and horizontal size | Patients who had PD had lower velocity compared with HCs D in most tasks; the PD group had a significant reduction in progressive vertical size, and the ET group had an increase in progressive horizontal size |
Abbreviations: PD: Parkinson's disease; on, on medication; off, off medication, HC, healthy controls; NIV, number of inversions in velocity; NIA, number of inversions in acceleration; EHC, elderly healthy controls; YHC, young health controls; ET, essential tremor.