RGC firing rate was calculated in 100 ms bins for individual retinas in light and in darkness. The Photoswitch Index was calculated in order to normalize light-elicited changes in firing rate of individual retinal ganglion cells and plotted as interquartile range (Boxplot). PI = (firing rate in the light − firing rate in darkness)/(firing rate in the light + firing rate in darkness). Data analysis was performed using custom routines in IgorPro software (Wavemetrics) or Matlab. In order to analyze oscillatory activity between 0 to 40 Hz we used the Chronux Matlab Package to calculate the multitaper spectrum over a moving window (mtspecgramc)20 ,21 (link). Raw data was converted to hdf5-files with no further preprocessing. Settings parameters were set to (‘tapers’, [5 9], ‘Fs’, 40000, ‘fpass’, [1 40], ‘pad’, 1, ‘trialave’, 1). Power is represented as µV2.
For analysis of ‘maximum frequency in power’ the peak of the highest frequency reaching a threshold of 4 SD was measured.
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