Handwriting movements for assessment of motor symptoms in schizophrenia spectrum disorders and bipolar disorder

Effect of stroke-induced memory impairment on handwriting-A forensic case study

Handwriting is an acquired neuromuscular skill that relies on motor memory and brain function, which make it vulnerable to impairments caused by physical or mental conditions. This paper presents a forensic case study comparing pre- and post-stroke Devnagari writing samples of a post-neurosurgery memory-impaired patient. The study aimed to assess the feasibility, reliability, and limitations of handwriting identification, in such cases. Results revealed that there are significant differences between pre- and post-stroke handwritings, indicating distinct master pattern and potentially different writers. In the absence of medical history, a false negative opinion could have been generated in this case. This study highlights the need for contemporaneous specimens, careful evaluation, and integration of medical history in forensic document examination. It is, certainly, a grey area, emphasizing the need for further research.

A new schizophrenia screening instrument based on evaluating the patient's writing

Formal Thought Disorder (FTD) is a defining feature of schizophrenia, which is often assessed through patients' speech. Meanwhile, the written language is less studied. The aim of the present study is to establish and validate a comprehensive clinical screening scale, capturing the full variety of empirical characteristics of writing in patients with schizophrenia. The 16-item Screening Instrument for Schizophrenic Features in Writing (SISFiW) is derived from detailed literature review and a "brainstorming" discussion on 30 samples written by patients with schizophrenia. One hundred and fifty-seven participants (114 patients with an ICD-10 diagnoses of schizophrenia; 43 healthy control subjects) were interviewed and symptoms assessed with the Positive and Negative Syndrome Scale (PANSS) and the Scale for the Assessment of Thought, Language, and Communication (TLC). Article samples written by each participant were rated with the SISFiW. Results demonstrated significant difference of the SISFiW-total between the patient group and healthy controls [(3.61 ± 1.72) vs. (0.49 ± 0.63), t = 16.64, p<0.001]. The inter-rater reliability (weighted kappa = 0.72) and the internal consistency (Cronbach's alpha coefficient = 0.613) were acceptable, but correlations with the criterion (PANSS and TLC) were unremarkable. The ROC analysis indicated a cutoff point at 2 with the maximal sensitivity (93.0 %)/specificity (93.0 %). Discriminant analysis of the SISFiW items yielded 8 classifiers that discriminated between the diagnostic groups at a perfect overall performance (with 90.4 % of original and 88.5 % cross-validated grouped cases classified correctly). This instrument appears to be practicable and reliable, with relatively robust discriminatory power, and may serve as a complementary tool to existing FTD rating scales.

Graphomotor Dysfluency as a Predictor of Disease Progression in Premanifest Huntington's Disease

BACKGROUND

Prior studies have relied on conventional observer-based severity ratings such as the Unified Huntington's Disease Rating Scale (UHDRS) to identify early motor markers of decline in Huntington's disease (HD).

OBJECTIVE

The present study examined the predictive utility of graphomotor measures handwriting and drawing movements.

METHODS

Seventeen gene-positive premanifest HD subjects underwent comprehensive clinical, cognitive, motor, and graphomotor assessments at baseline and at follow-up intervals ranging from 9-36 months. Baseline graphomotor assessments were subjected to linear multiple regression procedures to identify factors associated with change on the comprehensive UHDRS index.

RESULTS

Subjects were followed for an average of 21.2 months. Three multivariate regression models based on graphomotor variables derived from a complex loop task, a maximum speed circle drawing task and a combined task returned adjusted R2 coefficients of 0.76, 0.71, and 0.80 respectively accounting for a significant portion of the variability in cUHDRS change score. The best-fit model based on the combined tasks indicated that greater decline on the cUHDRS was associated with increased pen movement dysfluency and stroke-stroke variability at baseline.

CONCLUSION

Performance on multiple measures of graphomotor dysfluency assessed during the premanifest or prodromal stage in at-risk HD individuals was associated with decline on a multidimensional index of HD morbidity preceding an HD diagnosis.

An exploratory study on the handwritten allographic features of multi-ethnic population with different educational backgrounds

Ethnicity, native and/or foreign language knowledge, as well as the learned writing systems potentially influence the development of an individual’s handwriting. The unique education system consisting of National schools, Chinese-medium vernacular schools, Tamil-medium vernacular schools, and Islamic religious schools in Malaysia may have established specific characteristic handwritten allographic features that deserve investigation within the intelligence context. This study was aimed to explore handwritten allographic features of handwriting samples from 120 subjects (30 writers from four different educational backgrounds mentioned above). Characteristic features which could be attributed to the study groups were statistically analyzed and identified. In this study, thirteen allographic features, including letters "A", "B", "D", "H", "p", "T", "t", "w", "X" and "x", were found to be discriminative. Such information could serve to indicate the primary education system undergone by a writer; enabling the comparison of different handwriting profiles and allowing characterization of writers to a specific group of people.

Examining Motor Anticipation in Handwriting as an Indicator of Motor Dysfunction in Schizophrenia

Dysfunction in motor skills can be linked to alterations in motor processing, such as the anticipation of forthcoming graphomotor sequences. We expected that the difficulties in motor processing in schizophrenia would be reflected in a decrease of motor anticipation. In handwriting, motor anticipation concerns the ability to write a letter while processing information on how to produce the following letters. It is essential for fast and smooth handwriting, that is, for the automation of graphomotor gestures. In this study, we examined motor anticipation by comparing the kinematic characteristics of the first l in the bigrams ll and ln written on a digitiser. Previous studies indicated that the downstroke duration of the first l is modulated by the anticipation of the local constraints of the following letter. Twenty-four adult individuals with diagnosis of schizophrenia and 24 healthy adults participated in the study. The classic measures of duration (sec), trajectory (cm), and dysfluency (velocity peaks) were used for the kinematic analysis of the upstroke (US) and downstroke (DS). In the control group, the duration of the downstroke of the l was longer in ln than ll (US: ln = ll; DS: ln > ll) whereas no differences were found for the group with schizophrenia. Likewise, the control group showed a longer DS trajectory for the l of ln than ll in downstrokes, while the group of patients failed to show this effect. These results suggest that the motor alterations in patients with schizophrenia could also affect their ability for motor anticipation.

The Use of Handwriting Changes for the Follow-up of Patients with Bipolar Disorder

INTRODUCTION

Patients with bipolar disorder have motor skill deficiency and cognitive dysfunction. It is suggested that these deficiencies are related to the neurodevelopmental course of the disease. The aim of this study was to examine whether or not there was a change in the handwriting of patients with bipolar disorder in periods of mania and remission.

METHOD

Two samples of handwriting and signature were taken from the cases, one on admission before treatment and one just after discharge. The first sample was taken in the period when the patients hospitalised with manic episode before medications and the second sample was taken in remission when the decision for discharge was made. The handwriting changes betwen the manic episode and the remission period were examined.

RESULTS

In the examination of the handwriting between the two periods, there was an increase in the size of the writing, pen pressure, the length of words, the spaces between words, and missing and incorrect punctuation marks in the manic episode. There were no differences in any handwriting measure on function of the specific diagnosis or the antipsychotic dose but tremor count was higher in patients using antipsychotics (p<0.05). Most of the parameters showing a change were found to be related to the Young Mania Rating Scale (YMRS) scores.

CONCLUSION

The results of this study determined severe changes in the handwriting of patients with bipolar disorder in a period of mania. Handwriting features can be used to screen patients for discharge and can be used for prediction when a patient might switch into manic episode. Also intake YMRS scores were found as the most important feature that affect handwriting parameters in manic patients.

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.

Exploring the Relationship of Transdiagnostic Mood and Psychosis Symptom Domains with Motor Dysfunction

BACKGROUND

A number of motor abnormalities have been reported in psychotic disorders, including dyskinesia and psychomotor slowing. There is also evidence for many of the same motor abnormalities in biological first-degree relatives and accruing evidence for motor abnormalities in bipolar disorder. In addition to motor dysfunction, there are also shared symptom domains amongst these populations.

OBJECTIVES

We explored the associations of (1) current and lifetime psychosis and mood symptom domains and (2) domains of psychosis proneness with various domains of motor function in a transdiagnostic sample (n = 149).

METHOD

Individuals with schizophrenia, schizoaffective disorder, or bipolar disorder, biological first-degree relatives of individuals with a psychotic disorder, and controls completed measures of psychomotor speed and movement fluidity, and neural activity related to motor preparation (stimulus-locked lateralized readiness potential, S-LRP) and execution (response-locked LRP) was assessed using EEG. All participants completed the Brief Psychiatric Rating Scale; patients were additionally assessed for lifetime psychosis and mood episode symptoms, and relatives and controls completed the Chapman psychosis proneness scales.

RESULTS

Multiple regression revealed levels of current negative symptoms and mania were significantly positively associated with psychomotor slowing even after accounting for current antipsychotic medication dosage and duration of illness. S-LRP onset latency was significantly positively associated with magical ideation.

CONCLUSION

Domains of motor function are associated with various mood and psychosis symptom domains in a transdiagnostic sample, which may provide insight into brain abnormalities relevant to the expression of symptoms across disorders.

The computational analyses of handwriting in individuals with psychopathic personality disorder

The main aim of the present study was to examine several parameters of handwriting in order to identify the putative specific patterns of writing associated with psychopathic personality disorder. The hypothesis-generating study was carried out with the use of Mann-Whitney U test to compare two groups of prisoners, without p-value, effect size, and confidence intervals for effect size. The handwriting samples were obtained from two groups of individuals: prisoners diagnosed with psychopathic personality (n = 50), prisoners without psychopathic personality disorder (n = 30). Two groups were matched in terms of intellectual level, age, and education. The examined handwriting samples were identical. To examine graphical parameters such as structure, proportions, density, inter-spaces, and impulse, the computer programs GlobalGraf were used. This software is employed by Polish Forensic Association. The inter-group comparisons of graphical parameters have shown there is no significant difference (95% confidence intervals for the effect sizes included 0, or negative numbers) in handwriting between prisoners with psychopathic personality disorder and prisoners without this disorder. Logistic regression has been calculated to show whether any handwriting patterns allow to predict psychopathic personality disorder. Results indicate that participants with psychopathic personality disorder do not exhibit significant motor impairments manifesting in structural, density, topographic, proportions, letter spacing, and impulse features of handwriting. This suggests, contrary to many beliefs related to graphology, that psychopathic personality cannot be identified on the basis of computational forensic examination of handwriting.