Experiments concerning the human C-wave

Abstract

The dependence of the human c-wave from the step amplitude was studied qualitatively. The maximum of the c-wave is achieved with light stimuli longer than 10 sec. After a dark period of 10 sec a fully developed c-wave appears. Also, in response to a brilliant photoflash a c-wave could be recorded. The influence of a mobile pupil on the response in the DC-ERG is demonstrated. Responses of the retinal potential to square wave and sinusoidal stimuli of different period times have been registered.

A Soft Contact Lens for DC Registration of the Human ERG

“…2). Amplitude and latency of the illustrated c waves and the off effects as well as of the recorded a and b waves, accord with earlier publications [1,2,8],…”

“…Skoog and N ilsson [4] applied an averaging technique, whereas Taumer et at. [8] described an apparatus to achieve single registra tions. Technical difficulties and the necessity of cooperative patients pre vented, up to now, the general use of DC ERG in clinical diagnostics.…”

THE INFLUENCE OF STIMULUS DURATION ON THE HUMAN D. C. REGISTERED c‐WAVE

“…A similar pattern was reported by Taumer, Rodhe, Wichmann & Rover (1976). At stimulus durations 0.13, 0.25, 0.5 and I s a slow, negative off-effect (the h-wave according to Skoog, Welinder & Nilsson 1977) might reduce the peak of the c-wave.…”

“…The relationship between stimulus intensity and c-wave amplitude, the cyclic behaviour of the c-wave and the effect of ethyl alcohol on the c-wave were investigated in man (Skoog & Nilsson 1974a,b;Skoog 1974). A similar method was used in a paper by Taumer, Rodhe, Wichmann & Rover (1976), where, in the results of one experiment, they point out the influence of the stimulus duration and the off-effect on the human c-wave. However, the c-wave amplitude remained rather constant when measured from the preceding trough.…”

Correlation Between the c Wave and the Corneoretinal Potential in Man

“…The experiment was carried out under mydriasis. The bright and the dark periods last 11 s, so that the induced c wave has always passed its maximum [24], The SO system is stimulated by the light step of 5 log units (10-4 to 1 asb), which induces a maximum (light maximum/light peak) after 10 min and a minimum after 25 min. The value of the maximum is 2.5 mV above the steady state level at the beginning (basic level; BL).…”