[Muscle action potential following transcranial stimulation and absolute refractory time in somatosensory evoked...

The purpose of this paper is to report the motor action potential (MAP) following transcranial stimulation and absolute refractory time (ART) in somatosensory evoked potential (SSEP) in normal rabbits. Twenty rabbits were used for this study. The MAP was recorded from a needle electrode that was inserted to the thoracic erector spinae muscle, quadriceps muscle and crural triceps muscle. The transcranial stimulation was applied on the motor area of the cerebrum by using a high voltage stimulator. ART was thereby investigated with the double stimuli method in SSEP. The waveform of the MAP was very similar to that of MAP evoked by the stimulation of peripheral nerve. A high degree of correlation existed between the latency of the MAP and distance from the stimulation site to the recording site. The ART was less than 40 ms and its mean value was 25.0 ms.