Clinical Neuroscience

[Assessment of motor impairment with electromyography - the kinesiological EMG]

HORVÁTH Mónika, FAZEKAS Gábor

DECEMBER 20, 2003

Clinical Neuroscience - 2003;56(11-12)

[Kinesiological electromyography means the application of the surface EMG measurement technique during movement and locomotion. The authors investigated the motor impairments of the upper limb of patients with spastic hemiparesis. Surface EMG activity in musculus biceps brachii and musculus triceps brachii were recorded during voluntary elbow flexion and extension movements. In some cases even the raw EMG signals contain the accurate information but more often the recorded signals should further be processed to achieve more valuable data concerning muscle performance. The limitations of the technique underlines the importance of the several steps of the processing. The purpose of this study is to present a systematic description of the methods and the precise application of surface EMG. The authors give a comprehensive view of different processing methods and demonstrate the application areas of the kinesiological EMG.]

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[The vestibulospinal system plays determining role in the activation processes of elementary sensorymotor patterns characterised by the verticalisation of the trunk and elevation of the head. In the thirties of the last century János Szentágothai proved that axons of the vestibulospinal tract reach the cervical and thoracic spinal cord and innervate the muscles of the neck. Later he verified existence of various connections among the labyrinth, the vestibular system, and the motor nuclei of the III., IV. and the VI. cranial nerves. His studies explain the functional neuroanatomic background of sitting up, sitting and balancing in the air, head-elevation and head control during the execution of a special elementary sensorymotor pattern: ”sitting in air”. All these functions can be activated by labyrinthine stimulation long before the maturation of the corticospinal tract.]

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[The symbolic characters of the Seven Deadly Sins can be traced from time to time in the cultural history of human mankind, being directly specified in certain artistic products. Such are, among others, the painting entitled „The Seven Deadly Sins and the Four Last Things” by Hieronymus Bosch and the poems Divina Commedia and The Faerie Queene by Dante Alighieri and Edmund Spenser, respectively. However, there are several paragraphs referring to these behaviours of the Seven Deadly Sins in the Bible and in the dramas of William Shakespeare. The objective of the present review is to propose that dysfunctions in the central serotonergic system might be involved in the the neurobiology of these ’sinful’ behaviour patterns. Evidences indicate that behaviour traits such as Accidia (Sloth), Luxuria (Lust, Lechery), Superbia (Pride), Ira (Wrath, Anger), Invidia (Envy), Avaritia (Greed, Avarice), and Gula (Gluttony) can relate to the functional alterations of serotonin in the brain. Results of biochemical and molecular genetic (polymorphism) studies on the human serotonergic system (receptor, transporter, enzyme), findings of functional imaging techniques, effects of depletion (or supplementation) of the serotonin precursor tryptophan, data of challenge probe investigations directed to testing central serotonergic functions, alterations in the peripheral serotonin measures (platelet), and the changes in the CSF 5-hydroxy-indoleacetic acid content indicate such serotonergic involvement. Furthermore, results of animal experiments on behaviour change (aggressive, dominant or submissive, appetite, alcohol preference) attributed to serotonin status modification and the clinically evidenced therapeutic efficacy of pharmacological interventions, based on the modulation and perturbation of the serotonergic system (e.g. selective serotonin reuptake inhibitors), in treating the ’sinful’ behaviour forms and analogous pathological states reaching the severity of psychiatric disorders (depression, sexual disturbances, social phobia, impulsivity-aggression, obsessive-compulsive and related spectrum disorders, paranoid jealousy, eating disorders) all strongly suggest the possibility that brain serotonin dysfunctions might underlie the neurophysiology of the Seven Deadly Sins.]

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