Handwriting Movement Abnormalities in Older Adults with Silent Cerebral Small Vessel Disease-A Preliminary Study.

BACKGROUND: The features of cerebral small vessel disease (CSVD) range from occurrence of asymptomatic radiological markers to symptomatic characteristics that include cognitive deficits and gait decline. The aim of the present study was to examine whether handwriting movement is abnormal in older people with CSVD through handwriting and drawing tasks using digitized handwriting kinematic assessment technology. METHODS: Older subjects (n = 60) were grouped according to Fazekas score, with 16 in the Severe CSVD group, 12 in the Non-severe group and 32 in the Healthy group. Kinematic data were recorded and analyzed during handwriting and drawing tasks: signature; writing of Chinese characters ("" and ""); and Archimedes' spiral drawing. RESULTS: The Severe CSVD group showed lower velocity and higher tortuosity during signature writing, lower velocity of stroke #4 of "" and vertical size of "" than did the Non-severe and Healthy groups. Both Severe CSVD and Non-severe CSVD subjects displayed higher average normalized jerk than did the Healthy group. Partial correlation analysis adjusting for age, gender, education, and mini-mental state evaluation (MMSE) showed that CSVD burden was positively associated with tortuosity of signature and average normalized jerk of Archimedes' spiral, and was negatively associated with velocity of strokes #3 and #4 of "", as well as vertical size of "". CONCLUSIONS: Older adults with CSVD showed abnormal handwriting movement. And the handwriting abnormalities captured by digitized handwriting analysis were correlated with CSVD severity in users of simplified Chinese characters.

A quantitative measure of handwriting dysfluency for assessing tardive dyskinesia.

Tardive dyskinesia (TD) is a movement disorder commonly associated with chronic exposure to antidopaminergic medications, which may be in some cases disfiguring and socially disabling. The consensus from a growing body of research on the incidence and prevalence of TD in the modern era of antipsychotics indicates that this disorder has not disappeared continues to challenge the effective management of psychotic symptoms in patients with schizophrenia. A fundamental component in an effective strategy for managing TD is its reliable and accurate assessment. In the present study, we examined the clinical utility of a brief handwriting dysfluency measure for quantifying TD. Digitized samples of handwritten circles and loops were obtained from 62 psychosis patients with or without TD and from 50 healthy subjects. Two measures of dysfluent pen movements were extracted from each vertical pen stroke, including normalized jerk and the number of acceleration peaks. Tardive dyskinesia patients exhibited significantly higher dysfluency scores than non-TD patients and controls. Severity of handwriting movement dysfluency was correlated with Abnormal Involuntary Movement Scale severity ratings for some tasks. The procedure yielded high degrees of test-retest reliability. These results suggest that measures of handwriting movement dysfluency may be particularly useful for objectively evaluating the efficacy of pharmacotherapeutic strategies for treating TD.

Aged Patients With Severe Small Vessel Disease Exhibit Poor Bimanual Coordination During the Anti-Phase Horizontal Line Drawing Task.

The present study explores whether SVD affects bimanual coordination, which is easier to detect than by conventional, MRI-based methods. We tested nine severe SVD patients, eight non-severe (i.e., moderate or mild) SVD patients, eleven healthy age-matched controls, and eight young adults. They were grouped according to Fazekas scale and by age. Participants performed horizontal line drawings with both hands simultaneously on two pen tablets. The movements consisted of rhythmic patterns where participants used both hands to draw horizontal lines in anti-phase on two pen tablets. Each participant underwent a series of neuropsychiatric assessments. Results showed that SVD patients exhibited in each hand smaller horizontal movement amplitudes with variability larger compared to the healthy age-matched controls. Only movement amplitudes appeared to decrease significantly with severity of SVD. Interestingly, we found no relevant differences between the age-matched, elderly controls and the young controls. Therefore, this effect appeared indicative of SVD. The variability of the lines orthogonal to the horizontal lines of the left, non-dominant hand differed only between the severe SVD group and the other groups. Furthermore, partial correlations demonstrated that the mean horizontal movement amplitude of the left hand was positively associated with the clock drawing test score, and the inter-manual asynchrony of the horizontal movements was positively associated with the Trail Making Test-B time. These results indicated that SVD patients show poor bimanual coordination, as reflected by spatial features such as movement amplitudes and variabilities, and abnormal bimanual coordination was associated with executive dysfunction.

Relationship between Product and Process Characteristics of Handwriting Skills of Children in the Second Grade of Elementary School.

The purpose of this study was to analyze the relationship between the quality and speed of handwriting and the process characteristics of the handwriting of children in the second grade of elementary school considered as a function of age and gender. A sample of 57 children (mean age 7.25 years, SD 0.43) participated in the study. The Concise Assessment Method for Children's Handwriting (BHK) was used to assess the quality and speed of handwriting. The characteristics of the process of handwriting were assessed using MovAlyzeR® software. The handwriting of boys showed a significantly greater number of strokes and slanted more to the right than the handwriting of girls. Handwriting quality and speed significantly correlated with several process characteristics: the number of strokes, reaction time, duration, relative pen-down duration, average pen pressure, vertical size, horizontal size, road length, and average absolute velocity. This research contributes to the construction of normative values in the process characteristics of the handwriting of elementary school children and provides a promising step towards the early identification of difficulties that can lead to dysgraphia, thus preventing later difficulties in handwriting.

Handwriting movement kinematics for quantifying extrapyramidal side effects in patients treated with atypical antipsychotics.

Ongoing monitoring of neuroleptic-induced extrapyramidal side effects (EPS) is important to maximize treatment outcome, improve medication adherence and reduce re-hospitalization. Traditional approaches for assessing EPS such as Parkinsonism, tardive akathisia, or dyskinesia rely upon clinical ratings. However, these observer-based EPS severity ratings can be unreliable and are subject to examiner bias. In contrast, quantitative instrumental methods are less subject to bias. Most instrumental methods have only limited clinical utility because of their complexity and costs. This paper describes an easy-to-use instrumental approach based on handwriting movements for quantifying EPS. Here, we present findings from psychiatric patients treated with atypical (second generation) antipsychotics. The handwriting task consisted of a sentence written several times within a 2 cm vertical boundary at a comfortable speed using an inkless pen and digitizing tablet. Kinematic variables including movement duration, peak vertical velocity and the number of acceleration peaks, and average normalized jerk (a measure of smoothness) for each up or down stroke and their submovements were analyzed. Results from 59 psychosis patients and 46 healthy comparison subjects revealed significant slowing and dysfluency in patients compared to controls. We observed differences across medications and daily dose. These findings support the ecological validity of handwriting movement analysis as an objective behavioral biomarker for quantifying the effects of antipsychotic medication and dose on the motor system.

The nature of bradykinesia in schizophrenia treated with antipsychotics.

Recognizing drug-induced parkinsonian bradykinesia in psychosis patients can be challenging due to overlapping presentation with psychomotor slowing associated with depression, negative symptoms, or cognitive disturbances. In this study, we apply prior findings on the pathophysiology of bradykinesia in Parkinson's disease to gain an understanding of motor slowing in psychosis patients. Handwriting movements from 57 healthy participants and 70 psychosis patients were recorded on a digitizing tablet. Temporal and kinematic features were extracted from handwritten loops and circles. An independent objective measure based on peak velocity for circles written at maximum speed was used to classify patients as bradykinetic. Using a statistical cut-point derived from normative data, 64% of the patients met criterion for bradykinesia compared with 46% using a conventional observer-based severity rating scale. Bradykinetic patients produced handwriting movements with longer stroke durations, smaller amplitudes and lower peak velocities compared with non-bradykinetic patients. Thirty-six percent of the pen strokes produced by the bradykinetic patients were non-ballistic compare with 20% for the non-bradykinetic patients. The proportion of nonballistic movements observed in handwriting was unrelated to current antipsychotic dose, severity of negative psychosis or depression. The ease-of-use and standardization of a tablet-based approach to quantifying parkinsonian bradykinesia can aid in diagnosing parkinsonian bradykinesia in patients treated with antipsychotics.

Advances in graphonomics: studies on fine motor control, its development and disorders.

During the past 20 years graphonomic research has become a major contributor to the understanding of human movement science. Graphonomic research investigates the relationship between the planning and generation of fine motor tasks, in particular, handwriting and drawing. Scientists in this field are at the forefront of using new paradigms to investigate human movement. The 16 articles in this special issue of Human Movement Science show that the field of graphonomics makes an important contribution to the understanding of fine motor control, motor development, and movement disorders. Topics discussed include writer's cramp, multiple sclerosis, Parkinson's disease, schizophrenia, drug-induced parkinsonism, dopamine depletion, dysgraphia, motor development, developmental coordination disorder, caffeine, alertness, arousal, sleep deprivation, visual feedback transformation and suppression, eye-hand coordination, pen grip, pen pressure, movement fluency, bimanual interference, dominant versus non-dominant hand, tracing, freehand drawing, spiral drawing, reading, typewriting, and automatic segmentation.

Quantitative measurement of handwriting in the assessment of drug-induced parkinsonism.

Monitoring drug-induced side effects is especially important for patients who undergo treatment with antipsychotic medications, as these drugs often produce extrapyramidal side effects (EPS) resulting in movement abnormalities similar to parkinsonism. Scientists have developed several objective laboratory tests to measure and research drug-induced movement disorders, but equipment and tests are complex and costly and have not become accepted in large-scale, multi-site clinical trials. The goals of this study were to test whether a simple handwriting measure can discriminate between individuals with psychotropic-induced parkinsonism, Parkinson's disease, and healthy individuals, and to examine some of the psychometric properties of the measure. We examined pen movement kinematics during cursive writing of a standard word in 13 patients with idiopathic Parkinson's disease (PD), 10 schizophrenia patients with drug-induced parkinsonism (SZ), and 12 normal healthy control participants (NC). Participants were instructed to write the word "hello" in cursive twice, at three vertical height scales. Software was used for data acquisition and analysis of vertical stroke velocities, velocity scaling, and smoothness. There were four important results from this study: (1) both SZ patients with drug-induced EPS and PD participants exhibited impaired movement velocities and velocity scaling; (2) performance on the velocity scaling measure distinguished drug-induced EPS from normal with 90% accuracy; (3) SZ, but not PD participants displayed abnormalities in movement smoothness; and (4) there was a positive correlation between age and magnitude of the velocity scaling deficit in PD participants. This study demonstrates that kinematic analyses of pen movements during handwriting may be useful in detecting and monitoring subtle changes in motor control related to the adverse effects of psychotropic medications.

Adaptation to changes in vertical display gain during handwriting in Parkinson's disease patients, elderly and young controls.

Parkinson's disease (PD) patients, matched elderly controls, and normal young subjects were tested using a visuo-motor adaptation paradigm in which the gain of the vertical component of the visual feedback of handwriting was manipulated in real-time. Handwriting was performed on a digitizer tablet and displayed in real-time on a computer screen in front of the participant. Vision of the hand and pen was occluded. Feedback could be normal (pre- and post-exposure conditions), smaller, or larger than the actual handwriting (exposure conditions). All groups showed a gradual adaptation that compensated for the distorted visual feedback during the exposure conditions. Moreover, all the groups showed significant after-effects during the post-exposure conditions suggesting that all the participants learned to compensate for the novel display gains. Taken together, these data suggest that the mechanisms for visuo-motor adaptation to changes in vertical display gain during handwriting are robust to aging and early stage of PD. These results may have implications for the treatment of micrographia in Parkinsonism.

Manual disfluency in drawing while producing and listening to disfluent speech.

This study investigated the extent to which manual fluency was associated with speech fluency in fluent speakers engaged in dual motor tasks. Thirteen right-handed adult females repeatedly drew circles with a pen on a digitizer tablet under five conditions: (1) a baseline (without reading or listening to speech), (2) reading fluently, (3) reading disfluently, (4) listening to fluent speech, and (5) listening to disfluent speech. The primary measure of disfluency was normalized mean squared jerk (NJ) in the pen strokes. Pen stroke time (ST) and pressure (PP) were also measured. NJ of the circle movements was significantly increased in both the disfluent reading and the disfluent listening conditions (p<0.05), compared to the baseline condition. In the fluent listening and reading conditions, NJ in circle drawing was unaltered compared to the baseline condition. Relative to baseline, ST increased significantly (p<0.05), but to a similar extent in all experimental conditions. Significantly (p<.05) greater pen pressure were also found in the disfluent versus fluent conditions. Positive correlations (r=0.33-0.63) were found between NJ and ST across conditions. These findings demonstrate that in dual-tasks, speech fluency can influence manual fluency. This is consistent with the corpus of data showing neural connectivity between manual and speech tasks, as well between perception and production. The mirror neuron system is implicated as a mechanism involved in forging these links.

Handwriting analysis indicates spontaneous dyskinesias in neuroleptic naïve adolescents at high risk for psychosis.

Growing evidence suggests that movement abnormalities are a core feature of psychosis. One marker of movement abnormality, dyskinesia, is a result of impaired neuromodulation of dopamine in fronto-striatal pathways. The traditional methods for identifying movement abnormalities include observer-based reports and force stability gauges. The drawbacks of these methods are long training times for raters, experimenter bias, large site differences in instrumental apparatus, and suboptimal reliability. Taking these drawbacks into account has guided the development of better standardized and more efficient procedures to examine movement abnormalities through handwriting analysis software and tablet. Individuals at risk for psychosis showed significantly more dysfluent pen movements (a proximal measure for dyskinesia) in a handwriting task. Handwriting kinematics offers a great advance over previous methods of assessing dyskinesia, which could clearly be beneficial for understanding the etiology of psychosis.

Differential levels of speech and manual dysfluency in adults who stutter during simultaneous drawing and speaking tasks.

We examined the disruptive effects of stuttering on manual performance during simultaneous speaking and drawing tasks. Fifteen stuttering and fifteen non-stuttering participants drew continuous circles with a pen on a digitizer tablet under three conditions: silent (i.e., neither reading nor speaking), reading aloud, and choral reading (i.e., reading aloud in unison with another reader). We counted the frequency of stuttering events in the speaking tasks and measured pen stroke duration and pen stroke dysfluency (normalized jerk) in all three tasks. The control group was stutter-free and did not increase manual dysfluency in any condition. In the silent condition, the stuttering group performed pen movements without evidence of dysfluency, similar to the control group. However, in the reading aloud condition, the stuttering group stuttered on 12% of the syllables and showed increased manual dysfluency. In the choral reading condition stuttering was virtually eliminated (reduced by 97%), but manual dysfluency was reduced by only 47% relative to the reading aloud condition. Trials where more stuttered events were generally positively correlated with higher manual dysfluency. The results are consistent with a model in which episodes of stuttering and motor dysfluency are related to neural interconnectivity between manual and speech processes.

Handwriting movement analyses for monitoring drug-induced motor side effects in schizophrenia patients treated with risperidone.

Epidemiologic studies indicate that nearly 60% of schizophrenia (SZ) patients treated with conventional antipsychotic drugs develop extrapyramidal side effects (EPS) such as parkinsonism and tardive dyskinesia. Although the prevalence of EPS has decreased due to the newer antipsychotics, EPS continue to limit the effectiveness of these medicines. Ongoing monitoring of EPS is likely to improve treatment outcome or compliance and reduce the frequency of re-hospitalization. A quantitative analysis of handwriting kinematics was used to evaluate effects of antipsychotic medication type and dose in schizophrenia patients. Twenty-seven schizophrenia patients treated with risperidone, six schizophrenia patients who received no antipsychotic medication and 47 healthy comparison participants were enrolled. Participants performed a 20-min handwriting task consisting of loops of various sizes and a sentence. Data were captured and analyzed using MovAlyzeR software. Results indicated that risperidone-treated participants exhibited significantly more dysfluent handwriting movements than either healthy or untreated SZ participants. Risperidone-treated participants exhibited lower movement velocities during production of simple loops compared to unmedicated patients. Handwriting dysfluency during sentence writing increased with dose. A 3-factor model consisting of kinematic variables derived from sentence writing accounted for 83% (r=.91) of the variability in medication dose. In contrast, we found no association between observer-based EPS severity ratings and medication dose. These findings support the importance of handwriting-based measures to monitor EPS in medicated schizophrenia patients.