1993 年 5 巻 1 号 p. 73-80
The response of abdominal muscle to tapping stimulation was investigated in man. Phasic electromyogram (EMG) of abdominal external oblique muscle was recorded through a coaxial needle electrode simultaneously with the respiratory volume. Tapping stimulation was applied ipsilateral to the electrode using a moving coil driven by rectangular electrical pulses. The abdominal muscle was more sensitive to tapping stimulation in the expiratory phase than in the inspiratory phase. The respiratory discharge started earlier in the expiratory phase and continued even into the early inspiratory phase during tapping stimulation. These results suggest that the profile of abdominal EMG activity may reflect the waxing and waning of central respiratory drive potentials (CRDP), and tapping stimulation-induced afferent activity may lower the threshold of the expiratory motoneurons.
