caa a22 4500 469122978 CHVBK 20180323133144.0 cr unu---uuuuu 170328e19920301xx s 000 0 eng 10.1007/BF02368523 doi (NATIONALLICENCE)springer-10.1007/BF02368523 Comparison of rectangular and exponential current pulses for evoking sensation [Elektronische Daten] [Jerry Wessale, Leslie Geddes, Gregory Ayers, Kirk Foster] There exists a paucity of quantitative information comparing the stimulating currents for different waveforms. Thus, the objectives of this study was to compare the threshold peak current (I) for sensation using rectangular and exponential; that is, capacitor-discharge, cathodal pulses of equivalent pulse duration (d). In 10 human subjects, stimuli were applied to the skin of the forearm, andI was determined alternately for each current waveform at each of several pulse durations (d). Strength-duration curves for sensation were obtained usingd of 0.01-50 ms. The threshold peak current (I r ) for a rectangular pulse of durationd was compared to the threshold peak current (I cd ) for a capacitor-discharge pulse of durationd, whered was the time convalue. Chronaxie, the pulse duration at whichI is twice the infinite-duration current asymptote (i.e., the rheobase), was calculated for each waveform and subject using the Weiss-Lapicque expression for excitability.I cd was found to be always higher thanI r of equivalent duration. Chronaxie for the capacitor-discharge pulse was, on the average, twice that for the rectangular pulse (p<0.01). Moreover, the ratioI cd /I r increased with decreasingd. These results indicate that these two waveforms are not equivalent on the basis of an equal-charge requirement for excitation, particularly at the short pulse durations. Furthermore, they suggest the need of a better expression to describe the excitability characteristics of tissues. Pergamon Press Ltd., 1992 Sensation threshold nationallicence Stimulus threshold nationallicence Strength-duration curve nationallicence Wessale Jerry Abbott Laboratories, Cardiovascular Research, Abbott Park, IL aut Geddes Leslie William A. Hillenbrand Biomedical Engineering Center, Room 204, A.A. Potter Building, Purdue University, 47907, West Lafayette, IN aut Ayers Gregory Indiana University School of Medicine, Indianapolis, IN aut Foster Kirk William A. Hillenbrand Biomedical Engineering Center, Room 204, A.A. Potter Building, Purdue University, 47907, West Lafayette, IN aut Annals of Biomedical Engineering Kluwer Academic Publishers 20/2(1992-03-01), 237-244 0090-6964 20:2<237 1992 20 10439 https://doi.org/10.1007/BF02368523 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02368523 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Wessale Jerry Abbott Laboratories, Cardiovascular Research, Abbott Park, IL aut NATIONALLICENCE 700 1- Geddes Leslie William A. Hillenbrand Biomedical Engineering Center, Room 204, A.A. Potter Building, Purdue University, 47907, West Lafayette, IN aut NATIONALLICENCE 700 1- Ayers Gregory Indiana University School of Medicine, Indianapolis, IN aut NATIONALLICENCE 700 1- Foster Kirk William A. Hillenbrand Biomedical Engineering Center, Room 204, A.A. Potter Building, Purdue University, 47907, West Lafayette, IN aut NATIONALLICENCE 773 0- Annals of Biomedical Engineering Kluwer Academic Publishers 20/2(1992-03-01), 237-244 0090-6964 20:2<237 1992 20 10439 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer