An empirical study of the validity of handwriting analysis

The EPQ was administered to 99 Ss, and a handwriting sample provided by each. A professional graphologist undertook to analyse the handwritings, and fill in the EPQ as she thought would have been done by the respondents. Significant correlations were only obtained for the P category; neither E, nor N, nor the L scale showed significant correlations between Ss and the graphologist.     

Comparing the handwriting behaviours of true and false writing with computerized handwriting measures

The goal of this study is to compare the handwriting behaviours of true and false writing. Based on the cognitive load and dis‐automaticity known to be experienced while communicating a deceptive message, we hypothesized a difference (in temporal and spatial, pressure measures and peak velocities) between the handwriting of true vs. false messages. Thirty‐four participants wrote true and false sentences on a digitizer, which is part of a new system called the Computerized Penmanship Evaluation Tool (ComPET). The ComPET evaluates brain‐hand performance, as manifested through handwriting behaviour, and was found to be a valid measure for detecting the dis‐automaticity that is indicative of certain diseases in the clinical field. Differences were found in mean pressure, spatial measures (mean stroke length and mean stroke height), but no differences were found in temporal measures and in the number of peak velocities. The use of ComPET in lie detection is discussed. Copyright © 2009 John Wiley & Sons, Ltd.     

Ductus: A software package for the study of handwriting production

Ductus is a software tool designed to analyze and aid understanding of the processes underlying handwriting production. Ductus is a digitizer-based device that provides online information on the handwriting process. It consists of two distinct modules that operate independently. The first module concerns stimulus presentation. It is particularly suited to experiments with children and patients presenting handwriting pathologies. The second module is devoted to data analysis. Apart from the geometrical aspects of handwriting, such as trajectory formation, Ductus provides a wide range of kinematic information, such as velocity, duration, fluency, and pauses, linked to the mastery of the movement itself. Ductus is available free from the authors. It works on a Windows platform with Wacom digitizers.     

Dynamic time warping: a new method in the study of poor handwriting

Poor handwriting is a diagnostic criterion for developmental coordination disorder. Typical of poor handwriting is its low overall quality and the high variability of the spatial characteristics of the letters, usually assessed with a subjective handwriting scale. Recently, Dynamic Time Warping (DTW), a technique originally developed for speech recognition, was introduced for pattern recognition in handwriting. The present study evaluates its application to analyze poor handwriting. Forty children attending Dutch mainstream primary schools were recruited and based on their scores on the Concise Evaluation Scale for Children's Handwriting (Dutch abbreviation: BHK), 20 good and 20 poor writers (of whom 13 were scheduled for handwriting intervention) were identified. The groups were matched for age (7-9 years), school grade (grades 2 and 3) and handedness. The children subsequently wrote sequences of the letter "a" on a graphics tablet in three conditions (normal, fast, and accurate). Classical kinematics were obtained and for each individual letter DTW was used to calculate the distance from the mean shape. The DTW data revealed much higher variability in the letter forms of the poor writers that was independent of the kinematic results of larger trajectories, faster movements, and higher pen pressure. The current results suggest that DTW is a valid and objective technique for letter-form analysis in handwriting and may hence be useful to evaluate the rehabilitation treatments of children suffering from poor handwriting. In education research it may be exploited to explore how children (should) learn to write.     

Motor constancy and the upsizing of handwriting

Although handwriting can vary in size, it remains remarkably similar in form, demonstrating motor constancy (equivalence). A consideration of changes in writing size may indicate: (1) how rescaling is accomplished, and (2) those invariant features that remain constrained under size variation. In the experiment reported here nine participants wrote the word “minimum” (without dotting “i’s”) in cursive text, under three size conditions on a SmartBoard. The standard deviation of stroke slope did not change its relationship to mean stroke slope, but stroke durations and lengths did vary. Kinematic analysis indicated that the number of submovements, their efficiency, and their kinematic structure varied across the three writing size conditions. The results suggested that motor constancy does not merely reflect a simple change in a single parameter of scale.     

Focus of attention and automaticity in handwriting

This study investigated the nature of automaticity in everyday tasks by testing handwriting performance under single and dual-task conditions. Item familiarity and hand dominance were also manipulated to understand both cognitive and motor components of the task. In line with previous literature, performance was superior in an extraneous focus of attention condition compared to two different skill focus conditions. This effect was found only when writing with the dominant hand. In addition, performance was superior for high familiarity compared to low familiarity items. These findings indicate that motor and cognitive familiarity are related to the degree of automaticity of motor skills and can be manipulated to produce different performance outcomes. The findings also imply that the progression of skill acquisition from novel to novice to expert levels can be traced using different dual-task conditions. The separation of motor and cognitive familiarity is a new approach in the handwriting domain, and provides insight into the nature of attentional demands during performance.     

Functions of vision in the control of handwriting

Much recent work on handwriting has emphasized the organisational processes which occur before output and has minimised the role of feedback processes, although reports of dysgraphic patients suggest that such processes have an important role in control. In the experiment reported here subjects wrote a set of sentences in each of six conditions, three with sight of the hand, and three without. In each visual condition subjects wrote normally, while counting aloud, and while repeating a nonsense syllable aloud. The orientation of the written words to the horizontal was affected by the loss of vision rather than by the addition of a secondary task, but the errors produced during writing were very similar for the secondary task condition and the without-vision condition. Errors occur at several levels in the output system which suggests that the role of sensory feedback is a complex one. Editing or monitoring functions can be compared with place keeping or sequencing control functions but current models are not well enough specified to help us discriminate between these.     

Evaluating the coordination dynamics of handwriting

This study aims to test the hypothesis that handwriting is governed by the dynamics of non-linear coupled oscillators. Accordingly, its first goal is to identify preferred, basic graphic shapes corresponding to spontaneously stable combinations of the two frequency-locked oscillatory x-y components of the trajectories. Six participants were required to produce 26 ellipsoids of varying eccentricities and orientations presented consecutively on a graphic tablet. These shapes corresponded to a systematic manipulation of the relative phase and the relative amplitude of the oscillators by a constant step. Results showed that among those, only eight ellipsoids were produced in a spontaneous and stable fashion. They were characterized by attraction of nearby shapes, and by a higher accuracy and velocity. Alike all periodic motion, graphic skills, hence handwriting, exhibit preferred coordination patterns, which can be ascribed to the non-linear coupling of two oscillators.     

Automatic segmentation as a tool for examining the handwriting process of children with dysgraphic and proficient handwriting

The purpose of this study was to use an x-y digitizer to collect handwriting samples typical of those written by the child in his or her natural environment, to analyze these samples with novel segmentation algorithms, and to present them visually in ways that illuminate spatial and temporal dynamic features amongst children with dysgraphic and proficient handwriting. While using the POET software (Penmanship Objective Evaluation Tool), a paragraph was copied onto paper affixed to an x-y digitizer by third-grade students, 14 with proficient and 14 with poor handwriting. A segmentation algorithm was developed to automatically isolate writing segments. Results yielded significant differences between the groups in various measures, including the number of the raw segments (i.e., the number of segments before combined with letters), the number of reverse segments (i.e., when the participant returned to correct or complete a previously written segment), the number of letters per minute, and the mean "In-Air" time between letters. Variability in both the spatial and temporal domains of instances of the same letter throughout the text was greater among the dysgraphic handwriters in comparison to the variability among the proficient. These results demonstrated the potential of using automated analytic techniques and visual display to achieve a more comprehensive understanding of handwriting difficulties.     

Effects of spatial and motor demands in handwriting

Four experiments were conducted to study response programming in handwriting tasks. Twelve right-handed subjects wrote acoustically presented words and phrases, and their handwriting was digitally recorded. Changes in latency, movement time, trajectory length, and pen pressure were studied as a function of response complexity (i.e., word length, complexity of initial letter, and spacing distance). The lengthening of the spatiotemporal parameters preceding the more complex structures is interpreted to be a reflection of the effects of mental load. The results further indicate that the choice of a programming strategy is dependent on the structural complexity of the task. Writing pressure decreased as a function of increased sequence length. The findings support a hierarchical model of handwriting.