Properties of electrode used in electrodermal measurement.

Psychopathy, Fear Arousal and Anticipated Pain

“…The electrodes were similar to those described by Lykken (1959) and consisted of %-in. zinc discs fitted into small corn plasters filled wich zinc sulphate paste.…”

GSR and polarization capacity of skin

“…But the polarization hypothesis has not been universally accepted and, in particular, some authors attribute to the skin a considerable literal capacitance, similar to the capacitance across the cell membrane, and regard the decrease in skin impedance with increasing frequency to be primarily due to the change in capacitative reactanceo If that were the case, then the GSR might indeed be a decrease in ohmic resistance which simply cannot be observed at high frequencies due to the much larger shunting effect of skin capacitanceo The present experiment tests the polarization hypothesis in a more analytiC fashion by observing the change in current through the skin during the application of a square pulse of (constant) voltage across the skin o Method Three zinc electrodes (Lykken, 1959) on the palmar surface of the distal phalanges of three fingers of one hand were connected together to serve as the active electrode, giving a total area of about 201 cm 2 0 The reference was another zinc electrode over a drilled site on the forearm (Shackel, 1959) 0 The electrolyte was a 0007 molar solution of ZnS04 in a neutral ointment cream (Unibase) o The S was wired in series with a small signal resistor and the output of the pulse amplifier (an AEL 104A stimulator in some of our work, eogo, Figo 2, or a special power amplifier fed by Tektronix 161 pulse generators, eogo, Figo 1). One channel of a Tektronix 502 dual-beam oscilloscope monitored the 005 volt pulse across the skin while the second channel was connected to the series resistor to read the current through the tissue (only the waveforms from this channel are shown in the figures)o The total series resistance being small relative to the resistance of the S, the voltage waveform across the skin remained square and constant in spite of changes in skin conductance of the sort shown in the figureso Results…”

Electrodermal Activity in the 1980s: A Review

“…Silver-silver chloride (Ag/AgCI) laboratory-made (Venables & Sayer 1963) or commercially available electrodes are widely used: zinc-zinc sulphate electrodes (Lykken 1959) provide an alternative. Considerable care in preparation, maintenance, monitoring and use of electrodes is essential, particularly for endosomatic (SP) recording.…”