. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 380 PHILIP RUCK one for each cycle of the stimulus. The recording obtained using lead Ei-E3 (Fig. 3,&) also displays the responses to each cycle of the stimulus, but the wave form of the ERG is the diphasic type which Autrum (1950) described as charac- teristic of the fast eye. The recordings of Figures 3,a and 3,b were made at different amplifier gains so that the flicker potentials in Figure 3,& appear larger than those in 3,a. In order to compensate for this, a portion of each ERG was enlarged photographically (Fi
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 380 PHILIP RUCK one for each cycle of the stimulus. The recording obtained using lead Ei-E3 (Fig. 3,&) also displays the responses to each cycle of the stimulus, but the wave form of the ERG is the diphasic type which Autrum (1950) described as charac- teristic of the fast eye. The recordings of Figures 3,a and 3,b were made at different amplifier gains so that the flicker potentials in Figure 3,& appear larger than those in 3,a. In order to compensate for this, a portion of each ERG was enlarged photographically (Figs. 3,c and 3,rf) so as to make the vertical amplifica- tions identical. At the same amplification the amplitudes of the flicker potentials are approximately equal. The experiment demonstrates that a flicker potential is as prominent in the absence of cornea-positive components of the ERG as in their FIGURE 3. Responses in lead Ea-Eo (records a and c) and in E,-Ea (records h and </) to light flickering at 200/sec. In c and d vertical amplifications of portions of responses in (7 and b have been made equal photographically. DC amplification. Similar experiments were performed on 10 eyes. The only difference in results was that in five cases the brief, cornea-positive on-deflection in lead Ei-E2 could be seen clearly (Fig. 2,o), and in the other five it could not (Fig. 3,a). (2) All of the previous ERG's were recorded at the same stimulus intensity. The ERG's of Figure 4 illustrate the way in which wave form varies with stimulus intensity. All ERG's in Figure 4 were evoked by stimuli of 1/8-second duration, and all are steady-state responses to stimuli presented at a rate of I/sec. Stimulus intensity increases from left to right in each row. In lead Ei-E2 (Fig. 4, top row), the wave form is similar throughout the range of intensities. There is a sustained, cornea-negative potential plus a brief, cornea-positive on-deflection. The response simply increases in magnitu
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
