Characteristics of handwriting of patients with huntington's disease

Abstract

Patients with Huntington's disease exhibit poorer-quality handwriting, sometimes clinically exhibiting macrographia, an increase in the size of handwriting. To characterize deficits in handwriting of patients with Huntington's disease, we compared the writing of 12 young, 12 age-matched controls, and 12 patients with Huntington's disease. Subjects were asked to write the letter "l" four times, at a constant length, on a graphics tablet that sampled pen position at 200 Hz. Huntington's disease causes chorea (involuntary movement), akinesia (difficulty in initiating voluntary movement), and bradykinesia (slowness and difficulty in maintaining voluntary movement). To distinguish changes in handwriting quality due to involuntary movement from impairments of voluntary movement, handwriting samples with obvious choreic movements were analyzed separately from other handwriting samples. Several measures of quality of handwriting were considered, based on: the regularity and consistency of handwriting, the efficiency of movement trajectories, and the proportions of movement occurring at specific frequencies. Results suggested that Huntington's disease increases variability of movement parameters, and causes problems in producing smooth movements. Choreic movement was best characterized by the number of zero crossings in the velocity function relative to the prescribed number of writing strokes. We hypothesize that macrographia in Huntington's disease occurs when chorea predominates over bradykinesia. Comparisons were made between the handwriting of patients with Huntington's and Parkinson's diseases.

Feasibility of a home-based program to improve handwriting after stroke: a pilot study

“…Cognitive impairment post-stroke may also affect handwriting performance, as handwriting requires cognitive skills (Phillips, Bradshaw, Chiu, & Bradshaw, 1994;Tucha et al, 2006). Cognition is an important aspect of motor control.…”

“…Detailed analysis of the handwriting process is becoming increasingly available using computerised assessments, which measure temporal aspects such as speed, time spent with the pen on the page versus 'in air' time (Rosenblum, Parush, & Weiss, 2001), stroke durations (Falk, Tam, Schellnus, & Chau, 2011), and frequency of handwriting (van Drempt et al, 2011a). Computerised assessments have also been used to measure spatial and kinematic aspects of handwriting performance such as force regularity and consistency, movement trajectories (Phillips et al, 1994), position, angle and velocity of movement of the writing implement (Falk et al, 2011), and pressure exerted on the writing implement . Computerised assessments are also able to measure handwriting components such as grip strength and variations in the centre of mass, which are thought to correlate with legibility (Falk et al, 2011).…”

Statistical Shape Analysis of Handwriting of Patients with Multiple Sclerosis

“…5 There are studies about handwriting changes in neurological disorders, but most of them were concentrated on dystonia, stroke, Parkinson's or Huntington's disease. [6][7][8][9] Despite common occurrence of handwriting deficits in MS, there are a limited number of manuscripts on this aspect of MS in the literature. Some of them were done in MS patients with tremor; some in MS with a motor disorder of handwriting.…”

Macrographia

“…It might be seen in patients with cerebellar disease (Haymaker 1956) and basal ganglia dysfunctions such as Huntington disease (Phillips et al 1994). It has also been observed in a sample of patients with aphasia (Fradis and Leischner 1985).…”