The effects of dual tasking on handwriting in patients with Parkinson’s disease

Abstract

Previous studies have shown that patients with Parkinson's disease (PD) experience extensive problems during dual tasking. Up to now, dual-task interference in PD has mainly been investigated in the context of gait research. However, the simultaneous performance of two different tasks is also a prerequisite to efficiently perform many other tasks in daily life, including upper limb tasks. To address this issue, this study investigated the effect of a secondary cognitive task on the performance of handwriting in patients with PD. Eighteen PD patients and 11 age-matched controls performed a writing task involving the production of repetitive loops under single- and dual-task conditions. The secondary task consisted of counting high and low tones during writing. The writing tests were performed with two amplitudes (0.6 and 1.0cm) using a writing tablet. Results showed that dual-task performance was affected in PD patients versus controls. Dual tasking reduced writing amplitude in PD patients, but not in healthy controls (p=0.046). Patients' writing size was mainly reduced during the small-amplitude condition (small amplitude p=0.017; large amplitude p=0.310). This suggests that the control of writing at small amplitudes requires more compensational brain-processing recourses in PD and is as such less automatic than writing at large amplitudes. In addition, there was a larger dual-task effect on the secondary task in PD patients than controls (p=0.025). The writing tests on the writing tablet proved highly correlated to daily life writing as measured by the 'Systematic Screening of Handwriting Difficulties' test (SOS-test) and other manual dexterity tasks, particularly during dual-task conditions. Taken together, these results provide additional insights into the motor control of handwriting and the effects of dual tasking during upper limb movements in patients with PD.

Dual tasking in Parkinson’s disease: Cognitive consequences while walking.

“…Even under these conditions that were not particularly challenging, the participants with PD showed cognitive vulnerabilities, suggesting that deleterious effects on cognition may be more prevalent in everyday environments that are less predictable and that feature greater environmental demands. The cognitive consequences of PD on dual cognitive-motor tasks has been observed on other motor tasks such as swallowing (Troche, Okun, Rosenbek, Altmann, & Sapienza, 2014), handwriting (Broeder et al, 2014) and copying figures (De Lucia, Grossi, Mauro, & Trojano, 2015), with implications for the role of neurorehabilitation in enhancing motor function by targeting PD cognitive vulnerabilities (Conradsson et al, 2015). Ultimately, cognition may prove to be a modifiable treatment target, with cognitive enhancement also resulting in improvement of traditional PD motor symptoms.…”

Relearning of Writing Skills in Parkinson's Disease After Intensive Amplitude Training

“…They included simple repetitive prewriting tasks, avoiding the involvement of language and higher‐order cognitive demands and allowing accurate measurement of pure motor performance. Automatization of writing was measured with a dual task (DT) paradigm . Patients were asked to write a 3‐loop sequence in the presence of visual target zones while counting high or low tones (Supplementary Fig.…”

“…The Systematic Screening of Handwriting Difficulties (SOS) test was used to assess daily life writing. It involved writing a text for 5 minutes continuously and was previously used in PD …”

Motor automaticity in Parkinson's disease

“…Some findings support the assumption that impaired automaticity is a reason underlying micrographia. External visual, auditory or verbal cues or attention could increase the amplitude and diminish the amplitude variability of handwriting in PD (Oliveira et al, 1997; Swinnen et al, 2000; Nieuwboer et al, 2009; Bryant et al, 2010; Ringenbach et al, 2011), while dual-tasking significantly reduces writing amplitude in PD patients, but not in healthy controls (Broeder et al, 2014). …”