Handwriting performance in the absence of visual control in writer's cramp patients: Initial observations

BACKGROUND: The present study was aimed at investigating the writing parameters of writer's cramp patients and control subjects during handwriting of a test sentence in the absence of visual control. METHODS: Eight right-handed patients with writer's cramp and eight healthy volunteers as age-matched control subjects participated in the study. The experimental task consisted in writing a test sentence repeatedly for fifty times on a pressure-sensitive digital board. The subject did not have visual control on his handwriting. The writing performance was stored on a PC and analyzed off-line. RESULTS: During handwriting all patients developed a typical dystonic limb posture and reported an increase in muscular tension along the experimental session. The patients were significantly slower than the controls, with lower mean vertical pressure of the pen tip on the paper and they could not reach the endmost letter of the sentence in the given time window. No other handwriting parameter differences were found between the two groups. CONCLUSION: Our findings indicate that during writing in the absence of visual feedback writer's cramp patients are slower and could not reach the endmost letter of the test sentence, but their level of automatization is not impaired and writer's cramp handwriting parameters are similar to those of the controls except for even lower vertical pressure of the pen tip on the paper, which is probably due to a changed strategy in such experimental conditions

Technical Device for Prevention of Spinal Column Disorders. Pilot EMG Study for Estimation of Back Muscle Activity

One possible cause of abnormal spinal column curvatures in adolescents is standing in “bad posture” for a long time. If this bad habit can be corrected on time, by creating a dynamic stereotype for correct body position maintenance, further health problems can be avoided. To present a technical device for prevention of scoliotic deformations signaling when the angles of inclination forward or sideward are bigger than preliminary set ones. To elaborate an experimental protocol based on analysis of EMG activity (EMGs) of spine muscles for verification of its effect. Study design: Devising of the device and of software for EMGs processing. Pilot experiments were conducted recording EMGs of eight spinal muscles for estimation of the device efficiency. Different mathematical procedures were proposed and programmed for data processing and illustration. Two device prototypes (with sound and vibration signal) are developed and experimentally used. EMG data from 20 motor tasks (half of them with carrying the device) are processed. The device can be used as a simple tool for biofeedback-type pupil teaching of dynamic stereotype for right posture maintenance. The developed software for EMGs processing can be used for tracing the effect of using the device

Principle Generalized Net Model of a Human Stress Reaction

The present study was aimed at investigating the mechanism of a human stress reaction by means of Generalized Nets (GNs). A principle GN-model of the main structures, organs and systems of the human body taking part in the acute and chronic reaction of the organism to a stress stimulus is generated. A possible application of the GN-model of the human stress reaction for testing the effect of known or newly synthesized pharmacological products as well as of food supplements is discussed

Handwriting performance in the absence of visual control in writer's cramp patients: Initial observations-0

<p><b>Copyright information:</b></p><p>Taken from "Handwriting performance in the absence of visual control in writer's cramp patients: Initial observations"</p><p>BMC Neurology 2006;6():14-14.</p><p>Published online 4 Apr 2006</p><p>PMCID:PMC1456986.</p><p>Copyright © 2006 Chakarov et al; licensee BioMed Central Ltd.</p>ence "Die Wellen schlagen hoch" for control subject S7 (left part) and writer's cramp patient P4 (right part). The upper plots represent the X/Y coordinate plot of the tip of the writing pen on the digitizing tablet. The lower plots are the respective time courses on Z-axis for the vertical pressure. Under each the number of inversions of vertical pressure is given (NI). The continuous line denotes the pen trace on the tablet and the dotted one – the pen trace lifted. Note in the pen trace that the patient has a longer stroke length and trajectory on the paper with longer pen lift. Note also that the time course pattern of the vertical pressure for the patient is characterized by larger number of segments with more NI and lower vertical pressure. : mean group values and standard deviations (error bars) for 7 controls (grey column) and 7 patients (black column) for vertical pressure and number of inversions in velocity per stroke (NIV). The asterisk denotes a statistically significant difference between both groups (p < 0.05). Note the statistically significant lower vertical pressure for the patients