Publications by authors named "Andon Kossev"

The authors' aim was to investigate the changes of corticospinal excitability during kinesthetic illusions induced by tendon vibration. Motor-evoked potentials in response to transcranial magnetic stimulation were recorded from the vibrated flexor carpi radialis and its antagonist, extensor carpi radialis. The illusions were evoked under vision conditions without feedback for the position of the wrist (open or closed eyes).

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Purpose: The purpose of the present study was to investigate the effect of muscle vibration (MV) on short latency intracortical inhibition (SICI) and facilitation (ICF) assessed by paired-pulse transcranial magnetic stimulation (TMS).

Methods: Nineteen right-handed healthy subjects were investigat ed without and with MV of the right extensor carpi radialis (ECR), using single- and paired-pulse TMS with interstimulus interval (ISI) of 3 and 13 ms. Intensities of the conditioning and test stimulus were 70 and 120 % of the motor threshold at rest.

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Training of skilled movements leads to typical changes in motor evoked potentials (MEPs). To explore how such changes are related to motor performance and hand preference, a goal-directed movement task was implemented on a haptic interface. Right and left hands of right-handed subjects were trained in two sessions separated by a pause of 10 min.

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The aim of this study was to determine whether low-frequency whole-body vibration (WBV) modulates the excitability of the corticospinal and intracortical pathways related to tibialis anterior (TA) muscle activity, thus contributing to the observed changes in neuromuscular function during and after WBV exercise. Motor-evoked potentials (MEPs) elicited in response to transcranial magnetic stimulation (TMS) of the leg area of the motor cortex were recorded in TA and soleus (SOL) muscles of seven healthy male subjects whilst performing 330 s continuous static squat exercise. Each subject completed two conditions: control (no WBV) and WBV (30 Hz, 1.

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Branched surface EMG electrodes are bipolar electrodes with the hot signal pole referenced to two or more short-circuited leading-off surfaces. This technique provides stable recording of single motor unit potentials during real movements, up to maximal muscle contractions. The selective characteristic of branched electrodes is based on the same principles as the double differential detection system and spatial filtering technique proposed later.

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Transcranial magnetic stimulation (TMS) is a useful method to study pharmacological effects on motor cortex excitability. Zolpidem is a selective agonist of the benzodiazepine receptor subtype BZ1 and has a distinct pharmacological profile compared to diazepam. To study the different effects of these two drugs on the cortical inhibitory system, TMS was performed before and after administration of a single oral dose of zolpidem (10 mg) and diazepam (5 mg) in six healthy volunteers.

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Objective: The authors studied amyotrophic lateral sclerosis (ALS) patients using triple stimulation technique (TST) to detect upper motor neuron (UMN) involvement.

Methods: Nineteen ALS patients (aged 45-72 years) were enrolled in the study. According to the El Escorial criteria, 6 diagnoses were suspected or possible, 6 probable, and 7 definite.

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The influence of the intensity of the conditioning stimulus on intracortical inhibition (ICI) and intracortical facilitation (ICF) was assessed in a study using paired-pulse transcranial magnetic stimulation. Interstimulus intervals (ISIs) between conditioning and test stimuli were 3 msec and 13 msec. Latencies and areas of motor evoked potentials in response to the test stimulus were measured in the right extensor carpi radialis muscle.

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Using single and paired-pulse transcranial magnetic stimulation we compared the cortical excitability in two different age groups of healthy subjects (mean+/-SD age: 28.5+/-5.2 vs.

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The authors studied the effects of sensorimotor integration (corticocortical inhibition and facilitation during muscle vibration [MV]) in dystonic patients. Eleven patients with cervical dystonia and 11 age-matched healthy control subjects were enrolled in the study. They were examined using transcranial magnetic stimulation (TMS) and tonic proprioceptive input (MV).

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Invasive electrical stimulation of the motor cortex has been reported to be of therapeutic value in pain control. We were interested whether noninvasive repetitive transcranial magnetic stimulation (rTMS) of the primary motor cortex might also act beneficially. Twelve patients with therapy-resistant chronic pain syndromes (mean age 51.

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Objectives: Repetitive transcranial magnetic stimulation (rTMS) has been tried therapeutically in a variety of neuropsychiatric disorders. Both, inhibition and activation of cortical areas may be achieved using different stimulation parameters. Using low-frequency rTMS (0.

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