Neuropsychological analysis of a typewriting disturbance following cerebral damage

Following a left CVA, a skilled professional typist sustained a disturbance of typing disproportionate to her handwriting disturbance. Typing errors were predominantly of the sequencing type, with spatial errors much less frequent, suggesting that the impairment was based on a relatively early (premotor) stage of processing. Depriving the subject of visual feedback during handwriting greatly increased her error rate. Similarly, interfering with auditory feedback during speech substantially reduced her self-correction of speech errors. These findings suggested that impaired ability to utilize somesthetic information--probably caused by the subject's parietal lobe lesion--may have been the basis of the typing disorder.     

The impact of graphomotor demands on letter-like shapes recognition: A comparison between hampered and normal handwriting

Recent research suggests that graphic motor programs acquired through writing are part of letter representations and contribute to their recognition. Indeed, learning new letter-like shapes through handwriting gave rise to better recognition than learning through methods suppressing the graphomotor activity (e.g., typing or viewing). The present study aimed at further assessing the role of the graphic motor programs in letter-like shape recognition by disturbing the graphomotor activity during learning. We compared recognition performance following normal handwriting to recognition performance following hampered handwriting. Adult participants learned sets of symbols by copying them either with a standard pen or with a hampering writing tool. Recognition tests were administered immediately after the learning phase and again one week later. The results revealed lower recognition accuracy following hampered handwriting than following normal handwriting suggesting a contribution of graphomotor skills in the construction of letter representation.     

Reprint of ‘Age-related changes in executive control and their relationships with activity performance in handwriting’

Deterioration in the frontal and prefrontal cortex associated with executive functions (EF) occurs with age and may be associated with changes in daily performance. The aim of the present study was to describe changes occurring with age in Executive Functions (EF) and handwriting activity, as well as to analyze relationships between age, EF and handwriting performance. The study population included 80 healthy participants (aged 31 to 76+) living in the community. After answering five questions about their writing habits, the participants completed the Behavioral Assessment of the Dysexecutive Syndrome (BADS). In addition, they performed a handwriting task on a digitizer included in the Computerized Penmanship Evaluation Tool (ComPET), which provides kinematic measures of the handwriting process. Significant differences were found between the four age groups for both EF and temporal and spatial handwriting measures. A series of regressions indicated that age predicted 35% of the variance of the BADS profile score (EF control) and 32% of the variance of in-air time while writing. The results of this study indicated age effect on both EF control and handwriting performance. Possible implications for further research and clinical evaluation and intervention are discussed.     

The influence of writing practice on letter recognition in preschool children: a comparison between handwriting and typing

A large body of data supports the view that movement plays a crucial role in letter representation and suggests that handwriting contributes to the visual recognition of letters. If so, changing the motor conditions while children are learning to write by using a method based on typing instead of handwriting should affect their subsequent letter recognition performances. In order to test this hypothesis, we trained two groups of 38 children (aged 3-5 years) to copy letters of the alphabet either by hand or by typing them. After three weeks of learning, we ran two recognition tests, one week apart, to compare the letter recognition performances of the two groups. The results showed that in the older children, the handwriting training gave rise to a better letter recognition than the typing training.     

Handwriting process and product characteristics of children diagnosed with developmental coordination disorder

Deficits in handwriting performance limit the school participation of children with developmental coordination disorder (DCD). The aim of this study was to compare the handwriting process and product characteristics of children with DCD to those of typically developing (TD) children in order to determine the best means of differentiation between the groups. Participants were 40 children, from 7 to 10 years old. The experimental group consisted of 20 children who met the criteria of DCD, and the control group consisted of 20 age- and gender-matched controls. The children were asked to perform three graded writing tasks on an electronic tablet, which was part of a computerized handwriting evaluation system (ComPET), in order to obtain measures of their handwriting process. The children's handwriting product was then evaluated by the Hebrew Handwriting Evaluation (HHE). Results showed significant differences between the groups for the handwriting process measures (on-paper and in-air time, mean pressure) and for the handwriting product characteristics (global legibility, number of letters erased or overwritten, spatial arrangement, and number of letters written in the first minute). The discriminant analysis yielded a high significant discrimination (80-90%), with the 'number of letters erased or overwritten' variable as the most differentiating variable (-.67). We concluded that an evaluation of both handwriting process and product characteristics among children with DCD provides a more comprehensive picture of their deficits. Using this method may enable practitioners to focus on children's main deficits and to tailor intervention methods so as to prevent academic underachievement and its consequences on their emotional well-being.     

Visual detectability gradients: the effect of distractors in contralateral field

A number of studies involving recognition of tachistoscopically presented words have reported that the typical right visual field performance superiority associated with linguistic stimuli is enhanced by bilateral presentations (simultaneous stimuli in both visual half-fields) compared to unilateral presentations (stimuli in only one half-field on a trial). We have reported the same phenomenon, however, using visual spatial patterns in a search paradigm (E. W. Yund, R. Efron, & D. R. Nichols, 1990c. Brain and Cognition, 12, 117-127) and have accounted for it in terms of the operating characteristics of a visual scanning mechanism which serially examines a decaying neural representation of the stimuli. In the present experiment we attempted to exploit these operating characteristics to influence this difference between unilateral and bilateral presentations. The results not only are consistent with the assumptions of the scanning hypothesis but they also provide new information pertinent to the operating characteristics of this mechanism.     

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.     

A computerized multidimensional measurement of mental workload via handwriting analysis

The goal of this study was to test the effect of mental workload on handwriting behavior and to identify characteristics of low versus high mental workload in handwriting. We hypothesized differences between handwriting under three different load conditions and tried to establish a profile that integrated these indicators. Fifty-six participants wrote three numerical progressions of varying difficulty on a digitizer attached to a computer so that we could evaluate their handwriting behavior. Differences were found in temporal, spatial, and angular velocity handwriting measures, but no significant differences were found for pressure measures. Using data reduction, we identified three clusters of handwriting, two of which differentiated well according to the three mental workload conditions. We concluded that handwriting behavior is affected by mental workload and that each measure provides distinct information, so that they present a comprehensive indicator of mental workload.     

Efficacy of an explicit handwriting program

The aim of this study was to investigate the effects of an explicit handwriting program introduced during the first grade of elementary school. Grade 1 children (N=23) with an age range of 6.1 to 7.4 yr. (15 girls, 8 boys) were administered an additional handwriting program of two weekly sessions of 45 min. over six weeks. Another group of 19 Grade 1 children (11 girls, 8 boys) received only the regular handwriting program of one weekly session. The Concise Assessment Scale for Children's Handwriting was administered to measure the changes in quality and speed of handwriting. The children given the explicit program showed better quality and speed of handwriting than did the control group. Their handwriting was more regular, with fewer ambiguous letters and fewer incorrect relative heights.     

Asymmetrical number-space mapping in the avian brain

When trained to peck a selected position in a sagittally-oriented series of identical food containers, and then required to generalize to an identical series rotated by 90°, chicks identify as correct only the target position from the left end, while choosing the right one at chance. Here we show that when accustomed to systematic changes in inter-elements distances during training or faced with similar spatial changes at test, chicks identify as correct both the target positions from left and right ends. However, ordinal position is spontaneously encoded even when inter-element distances are kept fixed during training (in spite of the fact that distances between elements suffice for target identification without any numerical computation). We explain these findings in terms of intra-hemispheric coupling of bilateral numerical (ordinal) representation and unilateral (right hemispheric) spatial representation of the number line, producing differential allocation of attention in the left and right visual hemifields.     

中文书写者字迹识别的眼动研究

采用眼动技术,以不同整体书写风格的字迹为实验材料,探讨中文字迹识别的眼动模式。实验结果显示：随着整体书写风格一致性的变化,被试识别不同书写者中文字迹的反应时、注视次数,眼跳次数,兴趣区数及落入兴趣区的比率均表现出显著性差异。结论：（1）识别中文字迹依赖字迹整体书写风格;（2）中文字迹识别模式：在识别字迹时,优先采用字迹整体书写风格识别不同的字迹;（3）中文字迹识别属于图像识别加工。     

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.     

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.     

Comparing language lateralization determined by dichotic listening and fMRI activation in frontal and temporal lobes in children with epilepsy

We investigated the relationship between ear advantage scores on the Fused Dichotic Words Test (FDWT), and laterality of activation in fMRI using a verb generation paradigm in fourteen children with epilepsy. The magnitude of the laterality index (LI), based on spatial extent and magnitude of activation in classical language areas (BA 44/45, 21/22, 39) differed significantly for patients classified with unilateral left, compared to bilateral, language representation based on FDWT scores. Concordance with fMRI was higher for those classified with unilateral left, than bilateral language representation on the FDWT. Of note, asymmetry in temporal lobe, rather than frontal lobe, activation was more strongly related to the LI from the dichotic listening test. This study shows that the FDWT can provide a quick and valid estimate of lateralization in pre-surgical candidates, which can be readily adopted for other clinical or research purposes when an estimate of language dominance is desired.     

A paradigm for emulating the early learning stage of handwriting: Performance comparison between healthy controls and Parkinson’s disease patients in drawing loop shapes

We present a novel paradigm, aimed at emulating the early stage of handwriting learning in proficient writers, by asking them to produce a familiar shape through a novel (unfamiliar) motor plan. Handwriting of beginner writers is characterized by slower movements, reduced spatial precision, lower fluency and reduced force regulation compared to those observed in the handwriting production of proficient writers. Features observed in the ink trace obtained with the novel motor plan and performance comparison of the handwriting obtained by familiar and unfamiliar motor plan suggest that the proposed paradigm is able to elicit non-automated movements in proficient writers.As that produced by beginner writers, handwriting of Parkinson’s disease (PD) patients is characterized by lack of fluency, slowness and abrupt changes of direction. Furthermore, PD patients show impaired performance in learning novel motor behaviors, as well as in executing motor behaviors acquired before the onset of the disease. We used the proposed paradigm for comparing the performance achieved by healthy controls in writing a familiar shape through a novel motor plan with those obtained by PD patients performing a well-known motor plan for drawing the same shape. Our analysis points out some similarities between performance obtained by healthy controls and those obtained by PD patients, sustaining the hypothesis that the fine tuning of the motor plan parameters involved in the handwriting production is impaired by PD.     

Spatial neglect, Balint-Homes' and Gerstmann's syndrome, and other spatial disorders

Brain-damaged patients with lesion or dysfunction involving the parietal cortex may show a variety of neuropsychological impairments involving spatial cognition. The more frequent and disabling deficit is the syndrome of unilateral spatial neglect that, in a nutshell, consists in a bias of spatial representation and attention ipsilateral to of extrapersonal, personal (ie, the body) space, or both, toward the side of the hemispheric lesion. The deficit is more frequent and severe after damage to the right hemisphere, involving particularly the posterior-inferior parietal cortex at the temporo-parietal junction. Damage to these posterior parietal regions may also impair visuospatial short-term memory, which may be associated with and worsen spatial neglect. The neural network supporting spatial representation, attention and short-term memory is, however, more extensive, including the right premotor cortex. Also disorders of drawing and building objects (traditionally termed constructional apraxia) are a frequent indicator of posterior parietal damage in the left and in the right hemispheres. Other less frequent deficits, which, however, have a relevant localizing value, include optic ataxia (namely, the defective reaching of visual objects, in the absence of elementary visuo-motor impairments), which is typically brought about by damage to the superior parietal lobule. Optic ataxia, together with deficits of visual attention, of estimating distances and depth, and with apraxia of gaze, constitutes the severely disabling Balint-Holmes' syndrome, which is typically associated with bilateral posterior parietal and occipital damage. Finally, lesions of the posterior parietal lobule (angular gyrus) in the left hemisphere may bring about a tetrad of symptoms (left-right disorientation, acalculia, finger agnosia, and agraphia) termed Gerstmann's syndrome, that also exists in a developmental form.     

Do motor ability and handwriting kinematic measures predict organizational ability among children with Developmental Coordination Disorders?

Background and aimChildren with Developmental Coordination Disorders (DCD) exhibit deficient daily performance concealed in their perception–action mechanism. The aim of this study was to analyze behavior organization of children with DCD, in varied tasks that require generating and monitoring mental representations related to space and time inputs/requirements, for achieving better insight about their perception–action mechanism.MethodParticipants included 42 children aged 7–10, half of whom were defined with DCD and half were typically developing (TD). The children were matched for age, gender and school. They were evaluated using the Movement–ABC and performed three handwriting tasks on an electronic tablet that is part of a computerized system (ComPET – Computerized Penmanship Evaluation Tool). In addition, their teachers completed the Questionnaire for Assessing Students’ Organizational Abilities-Teachers (QASOA-T) to assess the children’s daily organizational ability.ResultsSignificant group differences (DCD versus controls) were found for all handwriting kinematic measures across the three handwriting tasks and for the children’s organizational abilities. Motor ability predicted a considerable percentage of the variance of the kinematic handwriting measures (30–37%), as well as a high percentage of the variance of their organizational abilities (67%). The coefficient of variance of the pen tilt added an additional 3% to the prediction of their organizational abilities.ConclusionsThe results of this study exhibited deficient ability among children with DCD in organizing their behavior in varied real-world tasks requiring generation and monitoring representation related to space and time. The significance of the results to understanding the performance mechanism and implication to the clinical field are discussed.     

旋转任务中3～5岁儿童空间物体位置编码的研究

本实验探讨3~5岁儿童在对空间物体位置进行编码时,能否有效采用心理旋转策略或根据物体"位置关系"来判断物体方位。实验采用3×4混合设计,在旋转条件下研究上述问题。结果表明:(1)在策略方面,儿童对心理旋转的使用要显著优于利用位置关系进行判断;(2)随着年龄增长,心理旋转的能力不断提高,5岁时进步尤其明显;(3)3~5岁儿童均不能自动利用位置关系对物体位置进行编码,但5岁儿童经提示后可采用此策略。     

3~5岁儿童理解和使用空间表征的特点

以96名3~5儿童为被试,采用自编的儿童空间表征实验任务,在语言表征、模型表征和图画表征三种空间表征形式上,考察了儿童理解和使用空间表征的发展特点。结果表明:(1)总体上,3~5岁儿童理解空间表征的发展水平均显著高于使用空间表征的发展水平。(2)3~5岁儿童理解和使用空间表征的发展表现出显著的年龄效应。(3)从不同的空间表证形式来看,3岁儿童理解语言表征的能力与理解模型表征的能力之间差异显著,4岁儿童使用语言表征的能力与使用模型表征的能力之间的差异、使用语言表征的能力与使用图画表征的能力之间的差异、以及使用模型表征的能力与使用图画表征的能力之间的差异都显著,其余形式的空间表征理解之间的差异或空间表征使用之间的差异在各年龄段中均不显著。