Experimental procedure Steps 5 and 6: Recording data (<i>in vitro</i> ERG recordings).

<p><b>A₁)</b> Snapshot of the Longterm Data Display (raw data) from MC_Rack. Note that on most electrodes the ganglion cell spikes mask the <i>in vitro</i> ERG responses (e.g. the electrode marked in orange). Only the highest contrast flash elicits a response that is visible on most electrodes (red asterisks), while on some electrodes without ganglion cell spikes the <i>in vitro</i> ERG responses are clearly visible (electrode marked in blue). Reference electrode 15 (REF) is on the left. <b>A₂)</b> Zoomed view of the electrode marked in blue from panel A₁ showing the responses to flash stimuli of different contrast (highest two contrasts marked with red asterisks). The low-pass filtered data around the time highlighted by the box is shown in B₁+B₂. <b>B₁)</b> Data Display with 200 Hz low-pass filter applied. There is a clear response on almost all electrodes. Not all spikes get filtered out by the low-pass filter. Note the different time scale than in A₁. <b>B₂)</b> Zoomed view of the electrode marked in blue from panel B₁ that shows a very clear low frequency <i>in vitro</i> ERG response without contamination by ganglion cell spikes.