Electromyographic single motor unit recordings were used to study the axonal conduction velocity and the axonal refractory period of 60 motor units in patients with severe motor neuron disease. Eighteen per cent of the motor units had abnormally low axonal conduction velocity probably due to secondary degenerative changes. Thirty-two per cent of the motor units had abnormally long axonal refrac...

Single unit potentials were recorded from sural and medial gastrocnemius nerves. Action potential amplitude, integrated area and half-width (duration) were approximately proportional to conduction velocity, raised to the powers 1.5, 1 and -0.5 respectively with the sural nerve, and 2, 1.5 and -0.5 for the medial gastrocnemius nerve. These empirical relationships were applied to the computation ...

It was the object of this study to measure the time course of the action potential in individual human sensory nerve fibres in relation to conduction properties of the axons. For this purpose, the technique of percutaneous microneurography was combined with intradermal electrical stimulation of distal portions of the axons. Recordings were made at the wrist level from 57 type-identified mechano...

Conduction velocity in the heart is dependent on two main factors: intercellular electrical coupling and cellular electrical excitability. There is significant redundancy, “conduction reserve”, in these parameters such that significant reduction in the conduction velocity of the action potential requires either a large change in one of these parameters or combined changes in both. We have used ...

With the use of a double stimulus technique, nerve fibre velocity range measurements were performed over a single conduction distance in 13 normal subjects and over two conduction distances in another 12 normal subjects. The velocity ranges were found to be dependent upon the conduction distance, owing to unknown refractory period delays. Refractory period values were calculated for the 12 subj...

Effects of carbon disulphide (CS2) on conduction velocity in sciatic and tibial nerve were investigated in rats exposed to CS2 vapour at concentrations of 0.9 mg/l or 1.6 mg/l of air for periods of 1.5, 3, 6, 9 and 12 months. The conduction velocity was measured on the day following each exposure period, and again, three and six months after the last day of exposure. The majority of exposed rat...

Depression of myocardial conduction velocity can be an important mechanism of action of antiarrhythmic drugs but it can also facilitate arrhythmogenesis. We used lidocaine in an anesthetized canine preparation to address the hypothesis that drug-induced rate-dependent conduction velocity depression causes ventricular tachyarrhythmias. A closely spaced square array of 64 electrodes was used to d...

BACKGROUND The incidence of obesity is increasing worldwide. The neuropathy associated with obesity, that is evident from disturbed nerve conduction, is one of the complications for which a number of treatment options are being considered. In this study, Simvastatin, a hydroxyl methyl glutaryl coenzyme A reductase inhibitor and alpha-tocopherol, a dietary antioxidant are compared for their effe...

OBJECTIVE To investigate the usefulness of a new parameter, the ratio of motor nerve conduction velocity to F-wave conduction velocity (M/F ratio), for the differential diagnosis of diabetic neuropathy. RESEARCH DESIGN AND METHODS Nerve conduction studies were conducted in 95 patients with diabetic neuropathy, 44 nondiabetic patients with peripheral neuropathy, and 24 normal control subjects....

A case of combined multiple sclerosis and demyelinating neuropathy is presented. Percutaneous electrical stimulation of the cortex and spinal cord has shown that pyramidal tract conduction time was prolonged and conduction velocity in the cord was 4 m/s. Motor conduction velocity in proximal segments of peripheral nerves was slowed to the same extent as in distal segments.