The Embodied Penman: Effector‐Specific Motor–Language Integration During Handwriting

Several studies have illuminated how processing manual action verbs (MaVs) affects the programming or execution of concurrent hand movements. Here, to circumvent key confounds in extant designs, we conducted the first assessment of motor–language integration during handwriting—a task in which linguistic and motoric processes are co‐substantiated. Participants copied MaVs, non‐manual action verbs, and non‐action verbs as we collected measures of motor programming and motor execution. Programming latencies were similar across conditions, but execution was faster for MaVs than for the other categories, regardless of whether word meanings were accessed implicitly or explicitly. In line with the Hand‐Action‐Network Dynamic Language Embodiment (HANDLE) model, such findings suggest that effector‐congruent verbs can prime manual movements even during highly automatized tasks in which motoric and verbal processes are naturally intertwined. Our paradigm opens new avenues for fine‐grained explorations of embodied language processes.     

Haptics in teaching handwriting: the role of perceptual and visuo-motor skills

Two studies were carried out in order to better understand the role of perceptual and visuo-motor skills in handwriting. Two training programs, visual-haptic (VH) and visual (V), were compared which differed in the way children explored the letters. The results revealed that improvements of VH training on letter recognition and handwriting quality were higher than improvements after V training. We suppose that VH training was more efficient because it improved both perceptual and visuo-motor skills. In the second experiment, in order to investigate the part of each component, we assessed the link between visuo-motor skills, perceptual skills and handwriting. The results showed that only the visuo-motor tasks predict handwriting copying performance. These results are discussed in relation to the respective roles of the perceptual and visuo-motor skills on letter shape learning and handwriting movement execution.     

Biomechanical analyses of prolonged handwriting in subjects with and without perceived discomfort

Since wrist-joint position affects finger muscle length and grip strength, we studied its biomechanical relevance in prolonged handwriting. We recruited participants from young adults, aged 18–24, and separated them into control (n = 22) and in-pain (n = 18) groups, based whether or not they experience pain while handwriting. The participants then performed a writing task for 30 min on a computerized system which measured their wrist-joint angle and documented their handwriting kinematics. The in-pain group perceived more soreness and had a less-extended wrist joint, longer on-paper time, and slower stroke velocity compared to control group. There was no significant difference in handwriting speed and quality between the two groups. The wrist extension angle significantly correlated with perceived soreness. Ergonomic and biomechanical analyses provide important information about the handwriting process. Knowledge of pen tip movement kinematics and wrist-joint position can help occupational therapists plan treatment for individuals with handwriting induced pain.     

Learning New Letter-like Writing Patterns Explicitly and Implicitly in Children and Adults

A handwriting task was used to test the assumption that explicit learning is dependent on age and working memory, while implicit learning is not. The effect of age was examined by testing both, typically developing children (5–12 years old, n = 81) and adults (n = 27) in a counterbalanced within-subjects design. Participants were asked to repeatedly write letter-like patterns on a digitizer with a non-inking pen. Reproduction of the pattern was better after explicit learning compared to implicit learning. Age had positive effects on both explicit and implicit learning; working memory did not affect learning in either conditions. These results show that it may be more effective to learn writing new letter-like patterns explicitly and that an explicit teaching method is preferred in mainstream primary education.     

Visual perceptual and handwriting skills in children with Developmental Coordination Disorder

ObjectiveChildren with Developmental Coordination Disorder demonstrate a lack of automaticity in handwriting as measured by pauses during writing. Deficits in visual perception have been proposed in the literature as underlying mechanisms of handwriting difficulties in children with DCD. The aim of this study was to examine whether correlations exist between measures of visual perception and visual motor integration with measures of the handwriting product and process in children with DCD.MethodThe performance of twenty-eight 8–14 year-old children who met the DSM-5 criteria for DCD was compared with 28 typically developing (TD) age and gender-matched controls. The children completed the Developmental Test of Visual Motor Integration (VMI) and the Test of Visual Perceptual Skills (TVPS). Group comparisons were made, correlations were conducted between the visual perceptual measures and handwriting measures and the sensitivity and specificity examined.ResultsThe DCD group performed below the TD group on the VMI and TVPS. There were no significant correlations between the VMI or TVPS and any of the handwriting measures in the DCD group. In addition, both tests demonstrated low sensitivity.ConclusionClinicians should execute caution in using visual perceptual measures to inform them about handwriting skill in children with DCD.     

Investigating how children produce rotation and pointing movements when they learn to write letters

How do children learn to write letters? During writing acquisition, some letters may be more difficult to produce than others because certain movement sequences require more precise motor control (e.g., the rotation that produces curved lines like in letter O or the pointing movement to trace the horizontal bar of a T). Children of ages 6–10 (N = 108) wrote sequences of upper-case letters on a digitizer. They varied in the number of pointing and rotation movements. The data revealed that these movements required compensatory strategies in specific kinematic variables. For pointing movements there was a duration decrease that was compensated by an increase in in-air movement time. Rotation movements were produced with low maximal velocity but high minimal velocity. At all ages there was a global tendency to keep stability in the tempo of writing: pointing movements exhibited a duration trade-off whereas rotation movements required a trade-off on maximal and minimal velocity. The acquisition of letter writing took place between ages 6 and 7. At age 8 the children shifted focus to improving movement control. Writing automation was achieved around age 10 when the children controlled movement duration and fluency. This led to a significant increase in writing speed.     

A computational model of Parkinsonian handwriting that highlights the role of the indirect pathway in the basal ganglia

Parkinsonian handwriting is typically characterized by micrographia, jagged line contour, and unusual fluctuations in pen velocity. In this paper we present a computational model of handwriting generation that highlights the role of the basal ganglia, particularly the indirect pathway. Whereas reduced dopamine levels resulted in reduced letter size, transition of STN–GPe dynamics from desynchronized (normal) to synchronized (PD) condition resulted in increased fluctuations in velocity in the model. We also present handwriting data from PD patients (n = 34) who are at various stages of disease and had taken medication various lengths of time before the handwriting sessions. The patient data are compared with those of age-matched controls. PD handwriting statistically exhibited smaller size and larger velocity fluctuation compared to normal handwriting.     

How do we code the letters of a word when we have to write it? Investigating double letter representation in French

How do we code the letters of a word when we have to write it? We examined whether the orthographic representations that the writing system activates have a specific coding for letters when these are doubled in a word. French participants wrote words on a digitizer. The word pairs shared the initial letters and differed on the presence of a double letter (e.g., LISSER/LISTER). The results on latencies, letter and inter-letter interval durations revealed that L and I are slower to write when followed by a doublet (SS) than when not (ST). Doublet processing constitutes a supplementary cognitive load that delays word production. This suggests that word representations code letter identity and quantity separately. The data also revealed that the central processes that are involved in spelling representation cascade into the peripheral processes that regulate movement execution.