The “handwriting brain”: A meta-analysis of neuroimaging studies of motor versus orthographic processes

Evaluating handwriting in children with developmental coordination disorder (DCD): Temporal, spatial, pressure and grip-force measures

BACKGROUND

Writing involves complex sensorimotor and biomechanical processes that regulate pressure on the writing surface. Researchers analyze writing to understand kinetics and kinematics by evaluating temporal, spatial, and pressure aspects, yet discerning writing surface pressure and pen-grip force remains challenging.

AIMS

To compare handwriting kinetics (pen grip-force and surface pressure) and kinematics (temporal-spatial) of children with developmental coordination disorder (DCD) with those of typically developing (TD) children.

METHODS AND PROCEDURES

Twenty-seven children with DCD aged 7-12 years and 27 TD children matched by age and gender copied a 29-word passage onto a computerized tablet. Temporal, spatial and surface pressure as well as pen grip-force were measured with a tablet and a wearable device respectively.

OUTCOMES AND RESULTS

The DCD group displayed significantly longer total writing time, mean letter time, and greater letter height, width, variance, spacing, area, and erasures than the TD group. Although there were no significant between-group differences in the surface pressure or maintaining pressure, the DCD group displayed weaker grip-force, p = .01, with greater variance.

CONCLUSIONS AND IMPLICATIONS

The DCD group's weaker grip-force dynamics correlated with reduced legibility, form, and prolonged writing duration, revealing insights into handwriting mechanisms, particularly grip force, crucial for effective clinical interventions.

Associative white matter tracts selectively predict sensorimotor learning

Human learning varies greatly among individuals and is related to the microstructure of major white matter tracts in several learning domains, yet the impact of the existing microstructure of white matter tracts on future learning outcomes remains unclear. We employed a machine-learning model selection framework to evaluate whether existing microstructure might predict individual differences in learning a sensorimotor task, and further, if the mapping between tract microstructure and learning was selective for learning outcomes. We used diffusion tractography to measure the mean fractional anisotropy (FA) of white matter tracts in 60 adult participants who then practiced drawing a set of 40 unfamiliar symbols repeatedly using a digital writing tablet. We measured drawing learning as the slope of draw duration over the practice session and measured visual recognition learning for the symbols using an old/new 2-AFC task. Results demonstrated that tract microstructure selectively predicted learning outcomes, with left hemisphere pArc and SLF3 tracts predicting drawing learning and the left hemisphere MDLFspl predicting visual recognition learning. These results were replicated using repeat, held-out data and supported with complementary analyses. Results suggest that individual differences in the microstructure of human white matter tracts may be selectively related to future learning outcomes.

Cortical and Subcortical Mechanisms of Orthographic Word-form Learning

We examined the initial stages of orthographic learning in real time as literate adults learned spellings for spoken pseudowords during fMRI scanning. Participants were required to learn and store orthographic word forms because the pseudoword spellings were not uniquely predictable from sound to letter mappings. With eight learning trials per word form, we observed changes in the brain's response as learning was taking place. Accuracy was evaluated during learning, immediately after scanning, and 1 week later. We found evidence of two distinct learning systems-hippocampal and neocortical-operating during orthographic learning, consistent with the predictions of dual systems theories of learning/memory such as the complementary learning systems framework [McClelland, J. L., McNaughton, B. L., & O'Reilly, R. C. Why there are complementary learning systems in the hippocampus and neocortex: Insights from the successes and failures of connectionist models of learning and memory. Psychological Review, 102, 419-457, 1995]. The bilateral hippocampus and the visual word form area (VWFA) showed significant BOLD response changes over learning, with the former exhibiting a rising pattern and the latter exhibiting a falling pattern. Moreover, greater BOLD signal increase in the hippocampus was associated with better postscan recall. In addition, we identified two distinct bilateral brain networks that mirrored the rising and falling patterns of the hippocampus and VWFA. Functional connectivity analysis revealed that regions within each network were internally synchronized. These novel findings highlight, for the first time, the relevance of multiple learning systems in orthographic learning and provide a paradigm that can be used to address critical gaps in our understanding of the neural bases of orthographic learning in general and orthographic word-form learning specifically.

Role of the Cerebellum in the Construction of Functional and Geometrical Spaces

The perceptual and motor systems appear to have a set of movement primitives that exhibit certain geometric and kinematic invariances. Complex patterns and mental representations can be produced by (re)combining some simple motor elements in various ways using basic operations, transformations, and respecting a set of laws referred to as kinematic laws of motion. For example, point-to-point hand movements are characterized by straight hand paths with single-peaked-bell-shaped velocity profiles, whereas hand speed profiles for curved trajectories are often irregular and more variable, with speed valleys and inflections extrema occurring at the peak curvature. Curvature and speed are generically related by the 2/3 power law. Mathematically, such laws can be deduced from a combination of Euclidean, affine, and equi-affine geometries, whose neural correlates have been partially detected in various brain areas including the cerebellum and the basal ganglia. The cerebellum has been found to play an important role in the control of coordination, balance, posture, and timing over the past years. It is also assumed that the cerebellum computes forward internal models in relationship with specific cortical and subcortical brain regions but its motor relationship with the perceptual space is unclear. A renewed interest in the geometrical and spatial role of the cerebellum may enable a better understanding of its specific contribution to the action-perception loop and behavior's adaptation. In this sense, we complete this overview with an innovative theoretical framework that describes a possible implementation and selection by the cerebellum of geometries adhering to different mathematical laws.

White matter associations with spelling performance

Multiple neurocognitive processes are involved in the highly complex task of producing written words. Yet, little is known about the neural pathways that support spelling in healthy adults. We assessed the associations between performance on a difficult spelling-to-dictation task and microstructural properties of language-related white matter pathways, in a sample of 73 native English-speaking neurotypical adults. Participants completed a diffusion magnetic resonance imaging scan and a cognitive assessment battery. Using constrained spherical deconvolution modeling and probabilistic tractography, we reconstructed dorsal and ventral white matter tracts of interest, bilaterally, in individual participants. Spelling associations were found in both dorsal and ventral stream pathways. In high-performing spellers, spelling scores significantly correlated with fractional anisotropy (FA) within the left inferior longitudinal fasciculus, a ventral stream pathway. In low-performing spellers, spelling scores significantly correlated with FA within the third branch of the right superior longitudinal fasciculus, a dorsal pathway. An automated analysis of spelling errors revealed that high- and low- performing spellers also differed in their error patterns, diverging primarily in terms of the orthographic distance between their errors and the correct spelling, compared to the phonological plausibility of their spelling responses. The results demonstrate the complexity of the neurocognitive architecture of spelling. The distinct white matter associations and error patterns detected in low- and high- performing spellers suggest that they rely on different cognitive processes, such that high-performing spellers rely more on lexical-orthographic representations, while low-performing spellers rely more on phoneme-to-grapheme conversion.

Written language preservation in glioma patients undergoing awake surgery: The value of tailored intra-operative assessment

Written language is increasingly important, as contemporary society strongly relies on text-based communication. Nonetheless, in neurosurgical practice, language preservation has classically focused on spoken language. The current study aimed to evaluate the potential role of intra-operative assessments in the preservation of written language skills in glioma patients undergoing awake surgery. It is the first feasibility study to use a standardized and detailed Written language battery in glioma patients undergoing awakening surgery. Reading and spelling were assessed pre- and post-operatively in eleven patients. Intra-operatively, 7 cases underwent written language assessment in addition to spoken object naming. Results show that reading and spelling deficits may arise before and after glioma surgery and that written language may be differently affected than spoken language. In our case series, task-specific preservation of function was obtained in all cases when a specific written language skill was monitored intra-operatively. However, the benefits of intra-operative testing did not always generalize, and non-monitored written language tasks may not be preserved. Hence, when a specific written language skill needs to be preserved, to facilitate return to work and maintain quality of life, results indicate that intra-operative assessment of that skill is advised. An illustrative case report demonstrates how profile analyses can be used pre-operatively to identify cognitive components at risk and intra-operatively to preserve written language abilities in clinical practice.

Lateralized Functional Connectivity of the Sensorimotor Cortex and its Variations During Complex Visuomotor Tasks

Previous studies have shown that the left hemisphere dominates motor function, often observed through homotopic activation measurements. Using a functional connectivity approach, this study investigated the lateralization of the sensorimotor cortex during handwriting and drawing, two complex visuomotor tasks with varying contextual demands. We found that both left- and right-lateralized connectivity in the primary motor cortex (M1), dorsal premotor cortex (PMd), somatosensory cortex, and visual regions were evident in adults (males and females), primarily in an interhemispheric integrative fashion. Critically, these lateralization tendencies remained highly invariant across task contexts, representing a task-invariant neural architecture for encoding fundamental motor programs consistently implemented in different task contexts. Additionally, the PMd exhibited a slight variation in lateralization degree between task contexts, reflecting the ability of the high-order motor system to adapt to varying task demands. However, connectivity-based lateralization of the sensorimotor cortex was not detected in 10-year-old children (males and females), suggesting that the maturation of connectivity-based lateralization requires prolonged development. In summary, this study demonstrates both task-invariant and task-sensitive connectivity lateralization in sensorimotor cortices that support the resilience and adaptability of skilled visuomotor performance. These findings align with the hierarchical organization of the motor system and underscore the significance of the functional connectivity-based approach in studying functional lateralization.

Exploring cerebral laterality of writing and the relationship to handedness: a functional transcranial Doppler ultrasound investigation

Cerebral lateralization of oral language has been investigated in a plethora of studies and it is well established that the left hemisphere is dominant for production tasks in the majority of individuals. However, few studies have focused on written language and even fewer have sampled left-handers. Writing comprises language and motor components, both of which contribute to cerebral activation, yet previous research has not disentangled. The aim of this study was to disentangle the language and motor components of writing lateralization. This was achieved through the comparison of cerebral activation during (i) written word generation and (ii) letter copying, as assessed by functional Transcranial Doppler (fTCD) ultrasound. We further assessed cerebral laterality of oral language. The sample was balanced for handedness. We preregistered the hypotheses that (i) cerebral lateralization of the linguistic component of writing would be weaker in left-handers compared to right-handers and (ii) oral language and the linguistic component of written language would not be correlated in terms of cerebral lateralization. No compelling evidence for either of our hypotheses was found. Findings highlight the complexity of the processes subserving written and oral language as well as the methodological challenges to isolate the linguistic component of writing.

The Modularity of Dysgraphia

Research regarding dysgraphia, an impairment in writing, is attaining more attention in recent times. The existing studies on dysgraphia draw insights from cognitive, behavioural, neurological, and genetic fields of knowledge. However, these multiple studies on dysgraphia fail to illustrate how these cognitive, behavioural, neurological, and genetic systems interact and intersect in dysgraphia. Therefore, the studies could not offer a comprehensive understanding of dysgraphia. In order to fill this gap, the review attempts to study dysgraphia using the notion of modularity by accommodating insights from cognitive, behavioural, neurological, and genetic aspects of dysgraphia. Such a profound understanding could facilitate an early diagnosis and holistic intervention towards dysgraphia.

Transcranial direct current stimulation in semantic variant of primary progressive aphasia: a state-of-the-art review

The semantic variant of primary progressive aphasia (svPPA), known also as "semantic dementia (SD)," is a neurodegenerative disorder that pertains to the frontotemporal lobar degeneration clinical syndromes. There is currently no approved pharmacological therapy for all frontotemporal dementia variants. Transcranial direct current stimulation (tDCS) is a promising non-invasive brain stimulation technique capable of modulating cortical excitability through a sub-threshold shift in neuronal resting potential. This technique has previously been applied as adjunct treatment in Alzheimer's disease, while data for frontotemporal dementia are controversial. In this scoped review, we summarize and critically appraise the currently available evidence regarding the use of tDCS for improving performance in naming and/or matching tasks in patients with svPPA. Clinical trials addressing this topic were identified through MEDLINE (accessed by PubMed) and Web of Science, as of November 2022, week 3. Clinical trials have been unable to show a significant benefit of tDCS in enhancing semantic performance in svPPA patients. The heterogeneity of the studies available in the literature might be a possible explanation. Nevertheless, the results of these studies are promising and may offer valuable insights into methodological differences and overlaps, raising interest among researchers in identifying new non-pharmacological strategies for treating svPPA patients. Further studies are therefore warranted to investigate the potential therapeutic role of tDCS in svPPA.

Enhancing Handwriting Performance of Children with Developmental Coordination Disorder (DCD) Using Computerized Visual Feedback

Recent studies have analyzed the writing metrics of children with developmental coordination disorder (DCD) using computerized systems. To date, the use of computerized visual feedback to improve handwriting has not been investigated. This study aimed to examine the effects of computerized visual feedback on handwriting performance in time, spatial orientation, and pressure indices for children with DCD. Twenty-seven children aged 7 to 12 years with DCD assessed by the Movement Assessment Battery for Children and the Developmental Coordination Disorder Questionnaire received one weekly intervention session for 8 weeks, during which they twice copied an excerpt onto a tablet. Once, they received visual feedback where the writing color corresponded to the degree of pressure on the writing surface, and once they received no visual feedback. The two conditions were counterbalanced throughout the sessions. Pre-intervention sessions were compared with post-intervention sessions and with new texts for time, spatial orientation, and pressure measures. The findings revealed significantly decreased total and mean letter writing, in-air, and writing time and increased capacity in the visual feedback condition. In the spatial variables, a significant decrease in letter height variance was found. Pressure increased significantly throughout the intervention with visual feedback, whereas it decreased post-test in the writing task in both conditions and was maintained in the new text. Visual feedback intervention can increase the kinesthetic-haptic feedback required to regulate pressure during writing, promoting more efficient feedforward processes and improving output quality and capacity. The training effectiveness was transferable, and the intervention accessibility could increase student autonomy.

Writing letters in two graphic systems: Behavioral and neural correlates in Latin-Arabic biscripters

Biscriptuality is the ability to read and write using two scripts. Despite the increasing number of biscripters, this phenomenon remains poorly understood. Here, we focused on investigating graphomotor processing in French-Arabic biscripters. We chose the French and Arabic alphabets because they have comparable visuospatial complexity and linguistic features, but differ dramatically in their graphomotor characteristics. In a first experiment we describe the graphomotor features of the two alphabets and showed that while Arabic and Latin letters are produced with the same velocity and fluency, Arabic letters require more pen lifts, contain more right-to-left strokes and clockwise curves, and take longer to write than Latin letters. These results suggest that Arabic and Latin letters are produced via different motor patterns. In a second experiment we used functional magnetic resonance imaging to ask whether writing the two scripts relies upon partially distinct or fully overlapping neural networks, and whether the elements of the previously described handwriting network are recruited to the same extent by the two scripts. We found that both scripts engaged the so-called "writing network", but that within the network, Arabic letters recruited the left superior parietal lobule (SPL) and the left primary motor cortex (M1) more strongly than Latin letters. Both regions have previously been identified as holding scale-invariant representations of letter trajectories. Arabic and Latin letters also activated distinct regions that do not belong to the writing network. Complementary analyses indicate that the differences observed between scripts at the neural level could be driven by the specific graphomotor features of each script. Overall, our results indicate that particular features of the practiced scripts can lead to different motor organization at both the behavioral and brain levels in biscripters.

Reading anxiety modulates the functional connectivity of the reading-related network during adult reading

Researchers have studied cognitive and linguistic skills in predicting reading abilities, but the impact of affective factors such as anxiety on reading at the neurobiological level is not well understood. Here, we used functional magnetic resonance imaging to investigate the neural correlates of reading anxiety in adult readers performing a semantic judgment task. The results showed that reading anxiety was significantly correlated with response time but not with accuracy. Neurobiologically, functional connectivity strength rather than activation level of semantic-related areas significantly predicted reading anxiety. Activation of regions (i.e., the right putamen and right precentral gyrus) external to the semantic-related areas positively correlated with reading anxiety levels. These findings suggest that reading anxiety influences adult reading by modulating functional connections of semantic-related areas and brain activation of semantic-unrelated areas. This study provides insights into the neural mechanisms underlying reading anxiety experienced by adult readers.

Associative white matter tracts selectively predict sensorimotor learning

Human learning is a complex phenomenon that varies greatly among individuals and is related to the microstructure of major white matter tracts in several learning domains, yet the impact of the existing myelination of white matter tracts on future learning outcomes remains unclear. We employed a machine-learning model selection framework to evaluate whether existing microstructure might predict individual differences in the potential for learning a sensorimotor task, and further, if the mapping between the microstructure of major white matter tracts and learning was selective for learning outcomes. We used diffusion tractography to measure the mean fractional anisotropy (FA) of white matter tracts in 60 adult participants who then underwent training and subsequent testing to evaluate learning. During training, participants practiced drawing a set of 40 novel symbols repeatedly using a digital writing tablet. We measured drawing learning as the slope of draw duration over the practice session and visual recognition learning as the performance accuracy in an old/new 2-AFC recognition task. Results demonstrated that the microstructure of major white matter tracts selectively predicted learning outcomes, with left hemisphere pArc and SLF 3 tracts predicting drawing learning and the left hemisphere MDLFspl predicting visual recognition learning. These results were replicated in a repeat, held-out data set and supported with complementary analyses. Overall, results suggest that individual differences in the microstructure of human white matter tracts may be selectively related to future learning outcomes and open avenues of inquiry concerning the impact of existing tract myelination in the potential for learning.

Significance statement

A selective mapping between tract microstructure and future learning has been demonstrated in the murine model and, to our knowledge, has not yet been demonstrated in humans. We employed a data-driven approach that identified only two tracts, the two most posterior segments of the arcuate fasciculus in the left hemisphere, to predict learning a sensorimotor task (drawing symbols) and this prediction model did not transfer to other learning outcomes (visual symbol recognition). Results suggest that individual differences in learning may be selectively related to the tissue properties of major white matter tracts in the human brain.

Positive changes to written language following phonological treatment in logopenic variant primary progressive aphasia: Case report

Phonological impairment contributes to deficits in repetition and spoken naming in logopenic variant Primary Progressive Aphasia (lvPPA), but weakened phonology can also affect written language skills. In this experimental case report, we demonstrate phonological text agraphia in a 71-year-old woman in the early stages of lvPPA that undermined her ability to write meaningful, grammatical sentences. We investigated the therapeutic value of a rigorous treatment protocol to strengthen phonological manipulation skills coupled with transcranial direct current stimulation (tDCS). Intervention took place 5 days a week for 2 weeks with active tDCS, followed by a 2-month rest period, and then a second period of phonological treatment with sham tDCS. Over the course of treatment, our participant demonstrated improved phonological transcoding and manipulation skills as well as marked improvement in the proportion of grammatically well-formed, meaningful written narratives. Improvements in spelling and letter selection were also observed. Treatment gains were documented during phonological intervention in both active tDCS and sham treatment phases and were maintained 2 months after the conclusion of intervention. Importantly, improvements were observed in the context of a progressive disorder. These data present compelling evidence regarding the impairment-based approach that targets compromised phonological skills, presenting opportunity for improving functional written communication skills relevant to the everyday lives of individuals with lvPPA.

A Crossed Pure Agraphia by Graphemic Buffer Impairment following Right Orbito-Frontal Glioma Resection

Pure agraphias are caused by graphemic buffer damage. The graphemic buffer stores graphemic representations that handle the transition from spelling lexicon to writing or oral spellings. The authors report a case of a crossed pure agraphia, following the post-surgical removal of a right frontal low-grade glioma in a right-handed French patient. He presented a pure agraphia displaying the features of a graphemic buffer impairment. Our patient only made spelling errors, whereas repetition and other oral language abilities remained perfect. We found a greater number of errors for longer stimuli, increased errors for the medially located graphemes, and agraphia for both words and non-words and error types, essentially consisting of omissions, substitutions, and letter transpositions. We also observed no significant effect of word frequency on spelling errors, but word length affected the rate of errors. The particularity of this case was linked to right frontal subcortical injuries in a right-handed subject. To our knowledge, it is the first report of a crossed pure agraphia caused by graphemic buffer impairment. Further studies are needed in order to analyse the role of subcortical structures, particularly the caudate nucleus in the graphemic buffer during writing tasks, as well as the participation of the non-dominant hemisphere in writing language.

Brain Correlates of Chinese Handwriting and Their Relation to Reading Development in Children: An fMRI Study

Handwriting plays an important role in written communication, reading, and academic success. However, little is known about the neural correlates of handwriting in children. Using functional magnetic resonance imaging (fMRI) and a copying task, we investigated regional brain activation and functional lateralization associated with Chinese handwriting in children (N = 36, 9-11 years old), as well as their relations to reading skills. We found significant activation of the bilateral frontal motor cortices, somatosensory cortex, intraparietal sulcus (IPS), fusiform gyrus (FuG), and cerebellum during handwriting, suggesting that an adult-like brain activation pattern emerges by middle childhood. Moreover, children showed left-lateralized and bilateral activation of motor regions and right-lateralized activation of the FuG and cerebellum during handwriting, suggesting that functional lateralization of handwriting is not fully established by this age. Finally, the activation of Exner's area and the lateralization of the IPS and cerebellum during handwriting were correlated with reading skills, possibly representing a neural link between handwriting and reading in children. Collectively, this study reveals the brain correlates of handwriting and their relation to reading development in Chinese children, offering new insight into the development of handwriting and reading skills.

A 90-channel triaxial magnetoencephalography system using optically pumped magnetometers

Magnetoencephalography (MEG) measures the small magnetic fields generated by current flow in neural networks, providing a noninvasive metric of brain function. MEG is well established as a powerful neuroscientific and clinical tool. However, current instrumentation is hampered by cumbersome cryogenic field-sensing technologies. In contrast, MEG using optically pumped magnetometers (OPM-MEG) employs small, lightweight, noncryogenic sensors that provide data with higher sensitivity and spatial resolution, a natural scanning environment (including participant movement), and adaptability to any age. However, OPM-MEG is new and the optimum way to design a system is unknown. Here, we construct a novel, 90-channel triaxial OPM-MEG system and use it to map motor function during a naturalistic handwriting task. Results show that high-precision magnetic field control reduced background fields to ∼200 pT, enabling free participant movement. Our triaxial array offered twice the total measured signal and better interference rejection compared to a conventional (single-axis) design. We mapped neural oscillatory activity to the sensorimotor network, demonstrating significant differences in motor network activity and connectivity for left-handed versus right-handed handwriting. Repeatability across scans showed that we can map electrophysiological activity with an accuracy ∼4 mm. Overall, our study introduces a novel triaxial OPM-MEG design and confirms its potential for high-performance functional neuroimaging.

Stroke disconnectome decodes reading networks

Cognitive functional neuroimaging has been around for over 30 years and has shed light on the brain areas relevant for reading. However, new methodological developments enable mapping the interaction between functional imaging and the underlying white matter networks. In this study, we used such a novel method, called the disconnectome, to decode the reading circuitry in the brain. We used the resulting disconnection patterns to predict a typical lesion that would lead to reading deficits after brain damage. Our results suggest that white matter connections critical for reading include fronto-parietal U-shaped fibres and the vertical occipital fasciculus (VOF). The lesion most predictive of a reading deficit would impinge on the left temporal, occipital, and inferior parietal gyri. This novel framework can systematically be applied to bridge the gap between the neuropathology of language and cognitive neuroscience.

Personality traits modulate the neural responses to handwriting processing

Handwriting is a vital skill for everyday human activities. It has a wealth of information about writers' characteristics and can hint toward underlying neurological conditions, such as Parkinson's disease, autism, dyslexia, and attention-deficit/hyperactivity disorder (ADHD). Many previous studies have reported a link between personality and individual differences in handwriting, but the evidence for the relationship tends to be anecdotal in nature. Using functional magnetic resonance imaging (fMRI), we examined whether the association between personality traits and handwriting was instantiated at the neural level. Results showed that the personality trait of conscientiousness modulated brain activation in the left premotor cortex and right inferior/middle frontal gyrus, which may reflect the impact of personality on orthography-to-grapheme transformation and executive control involved in handwriting. Such correlations were not observed in symbol-drawing or word-reading tasks, suggesting the specificity of the link between conscientiousness and handwriting in these regions. Moreover, using a connectome-based predictive modeling approach, we found that individuals' conscientiousness scores could be predicted based on handwriting-related functional brain networks, suggesting that the influence of personality on handwriting may occur within a broader network. Our findings provide neural evidence for the link between personality and handwriting processing, extending our understanding of the nature of individual differences in handwriting.

Functional brain networks underlying the interaction between central and peripheral processes involved in Chinese handwriting in children and adults

The neural mechanisms that support handwriting, an important mode of human communication, are thought to be controlled by a central process (responsible for spelling) and a peripheral process (responsible for motor output). However, the relationship between central and peripheral processes has been debated. Using functional magnetic resonance imaging, this study examined the neural mechanisms underlying this relationship in Chinese handwriting in 36 children (mean age = 10.40 years) and 56 adults (mean age = 22.36 years) by manipulating character frequency (a central variable). Brain network analysis showed that character frequency reconfigured functional brain networks known to underlie motor processes, including the somatomotor and cerebellar network, in both children and adults, indicating that central processing cascades into peripheral processing. Furthermore, the network analysis characterized the interaction profiles between motor networks and linguistic-cognitive networks, fully mapping the neural architecture that supports the interaction of central and peripheral processes involved in handwriting. Taken together, these results reveal the neural interface underlying the interaction between central and peripheral processes involved in handwriting in a logographic writing system, advancing our understanding of the neural basis of handwriting.

Disruption of Functional Brain Networks Underlies the Handwriting Deficit in Children With Developmental Dyslexia

Developmental dyslexia (DD) is a neurological-based learning disorder that affects 5-17.5% of children. Handwriting difficulty is a prevailing symptom of dyslexia, but its neural mechanisms remain elusive. Using functional magnetic resonance imaging (fMRI), this study examined functional brain networks associated with handwriting in a copying task in Chinese children with DD (n = 17) and age-matched children (n = 36). We found that dyslexics showed reduced network connectivity between the sensory-motor network (SMN) and the visual network (VN), and between the default mode network (DMN) and the ventral attention network (VAN) during handwriting, but not during drawing geometric figures. Moreover, the connectivity strength of the networks showing group differences was correlated with handwriting speed, reading and working memory, suggesting that the handwriting deficit in DD is linked with disruption of a large-scale brain network supporting motoric, linguistic and executive control processes. Taken together, this study demonstrates the alternations of functional brain networks that underly the handwriting deficit in Chinese dyslexia, providing a new clue for the neural basis of DD.

Neural Correlates of Handwriting Effects in L2 Learners

Learning to write involves integrating motor production and visual perception to develop orthographic representations. This study tries to test the effect of hand movement training as a pathway to neural correlates for L2 Chinese and L2 English readers. Twenty L2 Chinese and 20 L2 English (n = 20) adults participated in both behavioral and electroencephalogram (EEG) experiments. We designed six learning conditions: Hand Writing Chinese (HC), Viewing Chinese (VC), Drawing followed by Character Recognition in Chinese (DC), Hand Writing English (HE), Viewing English (VE), and Drawing followed by Word Recognition in English (DE). Behavioral and EEG results demonstrated that drawing facilitated visual word recognition in Chinese compared to viewing. The findings imply that hand movement could strengthen the neural processing and improve behavioral performance in Chinese character recognition for L2 Chinese learners and English word recognition for L2 Chinese learners. Furthermore, N170 amplitude at the drawing condition was positively correlated with N400 amplitudes. Thus, the early visual word recognition neural indicator (e.g., N170) was predictive of the late neural indicator of semantic processing (e.g., N400), suggesting that hand movement facilitates the neural correlates between early word recognition and later comprehension.

Comparative research on neural dysfunction in children with dyslexia under different writing systems: A meta-analysis study

Developmental dyslexia is a special learning disorder which is prevalent in all languages. A central question in dyslexia is whether the neural mechanism of their defects is universal or distinct in different writing systems. Using meta-analytic approach, we created meta-images using activation abnormalities in Chinese and alphabetic children with dyslexia to find convergence and divergence under different writing systems. The results revealed that dyslexic children have a universal attention-related dysfunction with hypoactivation in the left inferior frontal cortex (IFC) and the anterior cingulate cortex (ACC) under different writing systems, in spite of differences of degree and spatial extent in those regions. Alphabetic dyslexic children additionally showed hypoactivation in the left occipito-temporo-parietal regions. Chinese dyslexic children showed specific hyperactivation in the right postcentral gyrus, the left rectus, and the right middle temporal gyrus. The present meta-analysis for the first time showed both shared and distinct abnormalities in children with dyslexia under Chinese and alphabetic writing systems.

Cerebral laterality of writing in right- and left- handers: A functional transcranial Doppler ultrasound study

The cerebral lateralization of written language has received very limited research attention in comparison to the wealth of studies on the cerebral lateralization of oral language. The purpose of the present study was to further our understanding of written language lateralization, by elucidating the relative contribution of language and motor functions. We compared written word generation with a task that has equivalent visuomotor demands but does not include language: the repeated drawing of symbols. We assessed cerebral laterality using functional transcranial Doppler ultrasound (fTCD), a non-invasive, perfusion-sensitive neuroimaging technique in 23 left- and 31 right-handed participants. Findings suggest that the linguistic aspect of written word generation recruited more left-hemispheric areas during writing, in right-handers compared to left-handers. This difference could be explained by greater variability in cerebral laterality patterns within left-handers or the possibility that the areas subserving language in left-handers are broader than in right-handers. Another explanation is that the attentional demands of the more novel symbol copying task (compared to writing) contributed more right-hemispheric activation in right-handers, but this could not be captured in left-handers due to ceiling effects. Future work could investigate such attentional demands using both simple and complex stimuli in the copying condition.

A connectivity model of the anatomic substrates underlying Gerstmann syndrome

The Gerstmann syndrome is a constellation of neurological deficits that include agraphia, acalculia, left–right discrimination and finger agnosia. Despite a growing interest in this clinical phenomenon, there remains controversy regarding the specific neuroanatomic substrates involved. Advancements in data-driven, computational modelling provides an opportunity to create a unified cortical model with greater anatomic precision based on underlying structural and functional connectivity across complex cognitive domains. A literature search was conducted for healthy task-based functional MRI and PET studies for the four cognitive domains underlying Gerstmann’s tetrad using the electronic databases PubMed, Medline, and BrainMap Sleuth (2.4). Coordinate-based, meta-analytic software was utilized to gather relevant regions of interest from included studies to create an activation likelihood estimation (ALE) map for each cognitive domain. Machine-learning was used to match activated regions of the ALE to the corresponding parcel from the cortical parcellation scheme previously published under the Human Connectome Project (HCP). Diffusion spectrum imaging-based tractography was performed to determine the structural connectivity between relevant parcels in each domain on 51 healthy subjects from the HCP database. Ultimately 102 functional MRI studies met our inclusion criteria. A frontoparietal network was found to be involved in the four cognitive domains: calculation, writing, finger gnosis, and left–right orientation. There were three parcels in the left hemisphere, where the ALE of at least three cognitive domains were found to be overlapping, specifically the anterior intraparietal area, area 7 postcentral (7PC) and the medial intraparietal sulcus. These parcels surround the anteromedial portion of the intraparietal sulcus. Area 7PC was found to be involved in all four domains. These regions were extensively connected in the intraparietal sulcus, as well as with a number of surrounding large-scale brain networks involved in higher-order functions. We present a tractographic model of the four neural networks involved in the functions which are impaired in Gerstmann syndrome. We identified a ‘Gerstmann Core’ of extensively connected functional regions where at least three of the four networks overlap. These results provide clinically actionable and precise anatomic information which may help guide clinical translation in this region, such as during resective brain surgery in or near the intraparietal sulcus, and provides an empiric basis for future study.

Handwriting Declines With Human Aging: A Machine Learning Study

Background

Handwriting is an acquired complex cognitive and motor skill resulting from the activation of a widespread brain network. Handwriting therefore may provide biologically relevant information on health status. Also, handwriting can be collected easily in an ecological scenario, through safe, cheap, and largely available tools. Hence, objective handwriting analysis through artificial intelligence would represent an innovative strategy for telemedicine purposes in healthy subjects and people affected by neurological disorders.

Materials and Methods

One-hundred and fifty-six healthy subjects (61 males; 49.6 ± 20.4 years) were enrolled and divided according to age into three subgroups: Younger adults (YA), middle-aged adults (MA), and older adults (OA). Participants performed an ecological handwriting task that was digitalized through smartphones. Data underwent the DBNet algorithm for measuring and comparing the average stroke sizes in the three groups. A convolutional neural network (CNN) was also used to classify handwriting samples. Lastly, receiver operating characteristic (ROC) curves and sensitivity, specificity, positive, negative predictive values (PPV, NPV), accuracy and area under the curve (AUC) were calculated to report the performance of the algorithm.

Results

Stroke sizes were significantly smaller in OA than in MA and YA. The CNN classifier objectively discriminated YA vs. OA (sensitivity = 82%, specificity = 80%, PPV = 78%, NPV = 79%, accuracy = 77%, and AUC = 0.84), MA vs. OA (sensitivity = 84%, specificity = 56%, PPV = 78%, NPV = 73%, accuracy = 74%, and AUC = 0.7), and YA vs. MA (sensitivity = 75%, specificity = 82%, PPV = 79%, NPV = 83%, accuracy = 79%, and AUC = 0.83).

Discussion

Handwriting progressively declines with human aging. The effect of physiological aging on handwriting abilities can be detected remotely and objectively by using machine learning algorithms.

Cerebellar contributions to orthographic working memory: A single case cognitive neuropsychological investigation

Single case cognitive neuropsychological investigations involve the precise characterization of cognitive impairment at the level of an individual participant. This deep data precision affords a more fine-grained understanding of the cognitive and neural underpinnings of complex tasks, and continues to provide unique insights that inform theory in cognitive neuroscience. Here, we present a single case study of an individual, F.R., who suffered a stroke that led to chronic reading and writing problems that include an impairment to the orthographic working memory system proposed to be involved in both written language production and comprehension. Individuals who have been previously reported with a similar cognitive impairment commonly have left parietal lesions. However, F.R.'s orthographic working memory deficit resulted from damage to the right cerebellum, specifically to a region that is both structurally and functionally connected to the left parietal lobe and has been identified as part of the spelling network in previous meta-analyses of writing fMRI studies. From this lesion-symptom association, we argue that orthographic working memory is subserved by a cortical-cerebellar circuit, with damage at any point in the circuit resulting in an impairment to this function. Such a conclusion is warranted by observations from this single case approach, and we argue that these observations would likely have been missed if F.R. had been included in a larger, shallower group study. In addition to elucidating our understanding of the neural basis of spelling, this case study demonstrates the value that single case neuropsychology can continue to bring to cognitive neuroscience.

Neural Correlates of Executed Compared to Imagined Writing and Drawing Movements: A Functional Magnetic Resonance Imaging Study

Objective

In this study we used functional magnetic resonance imaging (fMRI) to investigate whether motor imagery (MI) of handwriting and circle drawing activates a similar handwriting network as writing and drawing itself.

Methods

Eighteen healthy right-handed participants wrote the German word “Wellen” and drew continuously circles in a sitting (vertical position) and lying position (horizontal position) to capture kinematic handwriting parameters such as velocity, pressure and regularity of hand movements. Afterward, they performed the same tasks during fMRI in a MI and an executed condition.

Results

The kinematic analysis revealed a general correlation of handwriting parameters during sitting and lying except of pen pressure during drawing. Writing compared to imagined writing was accompanied by an increased activity of the ipsilateral cerebellum and the contralateral sensorimotor cortex. Executed compared to imagined drawing revealed elevated activity of a fronto–parieto-temporal network. By contrasting writing and drawing directly, executed writing induced an enhanced activation of the left somatosensory and premotor area. The comparison of the MI of these tasks revealed a higher involvement of occipital activation during imagined writing.

Conclusion

The kinematic results pointed to a high comparability of writing in a vertical and horizontal position. Overall, we observed highly overlapping cortical activity except of a higher involvement of motor control areas during motor execution. The sparse difference between writing and drawing can be explained by highly automatized writing in healthy individuals.

Evidence of Altered Functional Connectivity at Rest in the Writing Network of Children with Dyslexia

Aim. Handwriting abilities in children with dyslexia (DYS) are not well documented in the current literature, and the presence of graphomotor impairment in addition to spelling impairment in dyslexia is controversial. Using resting-state functional connectivity (RSFC), the present study aims to answer the following question: are there markers of graphomotor impairment at rest in DYS children? Method. The participants were children with DYS and typically developing (TD) children (n = 32) from French-speaking primary schools (M_age = 9.3 years). The behavioural evaluation consisted of spelling and handwriting measures. Participants underwent a resting-state fMRI scan. Results. Analyses of RSFC focused on a brain region responsible for graphomotor processes—the graphemic/motor frontal area (GMFA). The RSFC between the GMFA and all other voxels of the brain was measured. Whole-brain ANOVAs were run to compare RSFC in DYS and TD children. The results demonstrated reduced RSFC in DYS compared to TD between the GMFA and brain areas involved in both spelling processes and motor-related processes. Conclusions. For the first time, this study highlighted a disruption of the writing network in DYS. By identifying functional markers of both spelling and handwriting deficits at rest in young DYS participants, this study supports the presence of graphomotor impairment in dyslexia.

Components of language processing and their long-term and working memory storage in the brain

There is a consensus that the temporal lobes are involved in representing various types of information critical for language processing, including phonological (i.e., speech sound), semantic (meaning), and orthographic (spelling) representations. An important question is whether the same regions that represent our long-term knowledge of phonology, semantics, and orthography are used to support the maintenance of these types of information in working memory (WM) (for instance, maintaining semantic information during sentence comprehension), or whether regions outside the temporal lobes provide the neural basis for WM maintenance in these domains. This review focuses on the issue of whether temporal lobe regions support WM for phonological information, with a brief discussion of related findings in the semantic and orthographic domains. Across all three domains, evidence from lesion-symptom mapping and functional neuroimaging indicates that parietal or frontal regions are critical for supporting WM, with different regions supporting WM in the three domains. The distinct regions in different domains argue against these regions as playing a general attentional role. The findings imply an interaction between the temporal lobe regions housing the long-term memory representations in these domains and the frontal and parietal regions needed to maintain these representations over time.

Deficient Interhemispheric Connectivity Underlies Movement Irregularities in Parkinson's Disease

BACKGROUND

Movement execution is impaired in patients with Parkinson's disease. Evolving neurodegeneration leads to altered connectivity between distinct regions of the brain and altered activity at interconnected areas. How connectivity alterations influence complex movements like drawing spirals in Parkinson's disease patients remains largely unexplored.

OBJECTIVE

We investigated whether deteriorations in interregional connectivity relate to impaired execution of drawing.

METHODS

Twenty-nine patients and 31 age-matched healthy control participants drew spirals with both hands on a digital graphics tablet, and the regularity of drawing execution was evaluated by sample entropy. We recorded resting-state fMRI and task-related EEG, and calculated the time-resolved partial directed coherence to estimate effective connectivity for both imaging modalities to determine the extent and directionality of interregional interactions.

RESULTS

Movement performance in Parkinson's disease patients was characterized by increased sample entropy, corresponding to enhanced irregularities in task execution. Effective connectivity between the motor cortices of both hemispheres, derived from resting-state fMRI, was significantly reduced in Parkinson's disease patients in comparison to controls. The connectivity strength in the nondominant to dominant hemisphere direction in both modalities was inversely correlated with irregularities during drawing, but not with the clinical state.

CONCLUSION

Our findings suggest that interhemispheric connections are affected both at rest and during drawing movements by Parkinson's disease. This provides novel evidence that disruptions of interhemispheric information exchange play a pivotal role for impairments of complex movement execution in Parkinson's disease patients.

Influence of visual control on the quality of graphic gesture in children with handwriting disorders

Handwriting disorders (HD) are considered one of the major public health problems among school-aged children worldwide with significant interference on academic performances. The current study hypothesized that HD could be partly explained by a deficit in sensory feedback processing during handwriting. To explore this hypothesis, we have analyzed the effect of vision suppression on postural-gestural and on spatial/temporal/kinematic organization of drawing during an early pre-scriptural loop task with a digital pen, under two conditions: eyes open and eyes closed. Data collected from 35 children with HD were compared to data collected from typical children (typical group) from primary schools. The HD group showed significantly poorer postural control and an improvement on the spatial/temporal/kinematic organization of drawings when they closed their eyes compared to eyes opened. While in the typical group, postural-gestural organization became significantly more mature but there was no significant influence found on spatial/temporal/kinematic parameters of the loops. Thus, handwriting disorders could be explained by both proprioceptive/kinesthetic feedback disabilities and a disruptive effect of the visual control on the quality of the pre-scriptural drawings among these children who have kinesthetic memory and visuospatial disabilities. The ability of directing the strokes would remain dependent on sensory feedbacks, themselves insufficiently efficient, which would lead to difficulties in reaching a proactive control of handwriting. This current research is a liable contribution to enhance clinical practice, useful in clinical decision-making processes for handwriting disorders remediation.

Temporally resolved neural dynamics underlying handwriting

How do the temporal dynamics of neural activity encode highly coordinated visual-motor behaviour? To capture the millisecond-resolved neural activations associated with fine visual-motor skills, we devised a co-registration system to simultaneously record electroencephalogram and handwriting kinematics while participants were performing four handwriting tasks (writing in Chinese/English scripts with their dominant/non-dominant hand). The neural activation associated with each stroke was clearly identified with a well-structured and reliable pattern. The functional significance of this pattern was validated by its significant associations with language, hand and the cognitive stages and kinematics of handwriting. Furthermore, the handwriting rhythmicity was found to be synchronised to the brain's ongoing theta oscillation, and the synchronisation was associated with the factor of language and hand. These major findings imply an implication between motor skill formation and the interplay between the rhythms in the brain and the peripheral systems.

Protracted Neural Development of Dorsal Motor Systems During Handwriting and the Relation to Early Literacy Skills

Handwriting is a complex visual-motor skill that affects early reading development. A large body of work has demonstrated that handwriting is supported by a widespread neural system comprising ventral-temporal, parietal, and frontal motor regions in adults. Recent work has demonstrated that this neural system is largely established by 8 years of age, suggesting that the development of this system occurs in young children who are still learning to read and write. We made use of a novel MRI-compatible writing tablet that allowed us to measure brain activation in 5-8-year-old children during handwriting. We compared activation during handwriting in children and adults to provide information concerning the developmental trajectory of the neural system that supports handwriting. We found that parietal and frontal motor involvement during handwriting in children is different from adults, suggesting that the neural system that supports handwriting changes over the course of development. Furthermore, we found that parietal and frontal motor activation correlated with a literacy composite score in our child sample, suggesting that the individual differences in the dorsal response during handwriting are related to individual differences in emerging literacy skills. Our results suggest that components of the widespread neural system supporting handwriting develop at different rates and provide insight into the mechanisms underlying the contributions of handwriting to early literacy development.

Curved vs. Straight-Line Handwriting Effects on Word Recognition in Typical and Dyslexic Readers Across Chinese and English

Handwriting serves to link auditory and motor routines with visual word processing, which is a hallmark of successful reading. The current study aims to explore the effect of multisensory integration as a pathway to neural specialization for print among typical and dyslexic readers across writing systems. We identified 9-10-year-old dyslexic Chinese children (n = 24) and their typically developing counterparts (n = 24) on whom we conducted both behavioral and electroencephalogram (EEG) experiments. We designed four learning conditions: Handwriting Chinese (HC), Viewing Chinese (VC), Drawing followed by Character Recognition in Chinese (D-C), and Drawing followed by Word Recognition in English (D-E). In both handwriting and drawing conditions, we also designed curved vs. straight-line stimuli. Both behavioral and EEG results showed that handwriting straight line strokes facilitated visual word recognition in Chinese compared to handwriting curved lines. Handwriting conditions resulted in a lateralization of the N170 in typical readers, but not the dyslexic readers. Interestingly, drawing curved lines facilitate word recognition in English among dyslexic readers. Taken together, the results of the study suggest benefits of handwriting on the neural processing and behavioral performance in response to Chinese character recognition and curved-line drawing effects on English word recognition among dyslexic readers. But the lack of handwriting effects in dyslexic readers suggest that students who have deficits in reading may also be missing the link between multisensory integration and word recognition in the visual word form areas. The current study results have implications for maintaining handwriting practices to promote perception and motor integration for visual word form area development for normal readers and suggest that drawing practices might benefit Chinese dyslexic readers in reading English.

Is Instructional Scaffolding a Better Strategy for Teaching Writing to EFL Learners? A Functional MRI Study in Healthy Young Adults

To test the scaffolding theory when applied to the teaching and learning of writing English as a foreign language, this cross-sectional study was conducted to collect physiological data. A total of 53 participants were randomly assigned into two groups, and brain activity was investigated during a guided-writing task using storytelling pictures. The writing task was further divided into four parts using graded levels of difficulty. The experimental group performed tasks in sequence from easy to difficult, whereas the comparison group performed the tasks at random. Outcomes included handwriting assessments and fMRI measurements. Writing outcome assessments were analyzed using SPSS, and scanned images were analyzed using Statistical Parametric Mapping (SPM) software. The results revealed a positive learning effect associated with scaffolding instruction. The experimental group performed better during the writing tasks, and the fMRI images showed less intense and weaker reactions in the language processing region than were observed in the comparison group. The fMRI results also presented the experimental group with reduced motor and cognitive functions when writing in English. This study provides insight regarding brain activity during writing tasks in humans and may have implications for English-language instruction.

Progressive macrographia for block letter writing: A case study

"Macrographia", a relatively rare symptom generally following cerebellar diseases, consists of an abnormally large handwriting. The case reported in the present investigation shows several outstanding features. First, it is of the progressive variety, letters increase in size as one goes through the word towards the lower-right portion of space. Moreover, it is limited to one allographic variety, that is, block letters. This phenomenon is previously unreported, all allographic varieties being usually equally affected. Finally, no prominent cerebellar or basal ganglia abnormality could be demonstrated with structural MRI or PET. From a cognitive point of view, a peculiar combination of spatial attention, executive function and working memory deficits is proposed to account for the progressive misalignment and elongation of individual letters when specifically writing in block prints. From an anatomical perspective, the pattern of multifocal lesions, encompassing multiple cortical areas in both hemispheres and the corpus callosum, may support this multi-componential interpretation of the reported phenomenon.

The painter who changed her brain at the flick of a switch

The study of artists with acquired brain damage is an empirical way to investigate the multiplicity of cerebral changes that occur with artistic training. We describe a talented painter with a left progressive cerebral lesion. In spite of losing function of her right hand, she regained dexterity of the left one in ten days for painting and drawing but not for writing. We discuss two potential explanations for her rapid recovery: (a) her extensive artistic training and/or (b) the slow-growing nature of her cerebral lesion.

Functional brain networks underlying automatic and controlled handwriting in Chinese

This study aimed to identify the functional brain networks underlying the distinctions between automatic and controlled handwriting in Chinese. Network-based analysis was applied to functional magnetic resonance imaging data collected while adult participants performed a copying task under automatic and speed-controlled conditions. We found significant differences between automatic and speed-controlled handwriting in functional connectivity within and between the frontoparietal network, default mode network, dorsal attention network, somatomotor network and visual network; these differences reflect the variations in general attentional control and task-relevant visuomotor operations. However, no differences in brain activation were detected between the two handwriting conditions, suggesting that the reorganization of functional networks, rather than the modulation of local brain activation, underlies the dissociations between automatic and controlled handwriting in Chinese. Our findings illustrate the brain basis of handwriting automaticity, shedding new light on how handwriting automaticity may be disrupted in individuals with neurological disorders.

The brain basis of handwriting deficits in Chinese children with developmental dyslexia

Abundant behavioral studies have demonstrated high comorbidity of reading and handwriting difficulties in developmental dyslexia (DD), a neurological condition characterized by unexpectedly low reading ability despite adequate nonverbal intelligence and typical schooling. The neural correlates of handwriting deficits remain largely unknown; however, as well as the extent that handwriting deficits share common neural bases with reading deficits in DD. The present work used functional magnetic resonance imaging to examine brain activity during handwriting and reading tasks in Chinese dyslexic children (n = 18) and age-matched controls (n = 23). Compared to controls, dyslexic children exhibited reduced activation during handwriting tasks in brain regions supporting sensory-motor processing (including supplementary motor area and postcentral gyrus) and visual-orthography processing (including bilateral precuneus and right cuneus). Among these regions, the left supplementary motor area and the right precuneus also showed a trend of reduced activation during reading tasks in dyslexics. Moreover, increased activation was found in the left inferior frontal gyrus and anterior cingulate cortex in dyslexics, which may reflect more efforts of executive control to compensate for the impairments of motor and visual-orthographic processing. Finally, dyslexic children exhibited aberrant functional connectivity among brain areas for cognitive control and sensory-motor processes during handwriting tasks. Together, these findings suggest that handwriting deficits in DD are associated with functional abnormalities of multiple brain regions implicated in motor execution, visual-orthographic processing, and cognitive control, providing important implications for the diagnosis and treatment of dyslexia.

Neuroanatomical correlates of self-awareness of highly practiced visuomotor skills

Metacognition is the ability to introspect and control ongoing cognitive processes. Despite the extensive investigation of the brain architectures supporting metacognition for perception and memory, little is known about the neural basis of metacognitive capacity for motor function, a vital aspect of human behavior. Here, using functional and structural magnetic resonance imaging (MRI), we examined the brain substrates underlying self-awareness of handwriting, a highly practiced visuomotor skill. Results showed that experienced adult writers generally overestimated their handwriting quality, and such overestimation was more pronounced in men relative to women. Individual variations in self-awareness of handwriting quality were positively correlated with gray matter volume in the left fusiform gyrus, right middle frontal gyrus and right precuneus. The left fusiform gyrus and right middle frontal gyrus are thought to represent domain-specific brain mechanisms for handwriting self-awareness, while the right precuneus that has been reported in other domains likely represents a domain-general brain mechanism for metacognition. Furthermore, the activity of these structurally related regions in a handwriting task was not correlated with self-awareness of handwriting, suggesting the correlation with metacognition was independent of task performance. Together, this study reveals that metacognition for practiced motor skills relies on both domain-general and domain-specific brain systems, extending our understanding about the neural basis of human metacognition.

Effect of Handwriting on Visual Word Recognition in Chinese Bilingual Children and Adults

In a digital era that neglects handwriting, the current study is significant because it examines the mechanisms underlying this process. We recruited 9- to 10-year-old Chinese children (n = 24), who were at an important period of handwriting development, and adult college students (n = 24), for both behavioral and electroencephalogram (EEG) experiments. We designed four learning conditions: handwriting Chinese (HC), viewing Chinese (VC), drawing shapes followed by Chinese recognition (DC), and drawing shapes followed by English recognition (DE). Both behavioral and EEG results showed that HC facilitated visual word recognition compared to VC, and behavioral results showed that HC facilitated visual word recognition compared to drawing shapes. HC and VC resulted in a lateralization of the N170 in adults, but not in children. Taken together, the results of the study suggest benefits of handwriting on the neural processing and behavioral performance in response to Chinese characters. The study results argue for maintaining handwriting practices to promote the perception of visual word forms in the digital age.

Dysgraphia and dysprosody in a patient with arteriovenous malformation: a case report

Arteriovenous malformation (AVM) results from development of abnormal connections between veins and arteries. This study reported anAVM case suffering from dysgraphia and dysprosody. According to the results after the trauma, the patient's handwriting was identified as macrographic and illegible, and written letters and verbs were neglected in free writing or dictation. Moreover, prosody of the patient's utterances was changed. Finally, an intervention was conducted to improve the writing impairments whereby they eventually enhanced. AVM can adversely affect communication opportunities and working life due to these impairments. Thus referring the patient to speech and language pathologists seems sensible and necessary.