Changes in the electroretinogram of compound eyes of the cockroach Periplaneta americana L. upon ocelli shielding

The cockroach visual system comprises compound eyes with photoreceptors of two spectral classes and ocelli – simple eyes consisting of green-sensitive photoreceptors. Using the method of non-invasive electroretinogram (ERG) recording from both compound eyes, it was shown that shielding of both ocelli leads to a significant alteration of ERG parameters, namely, an increase in the amplitude of responses to short-wavelength stimuli of saturating intensity and a slowing down of responses to both short-wavelength and long-wavelength light. Ocelli estimating the total light level modulate the functioning of photoreceptors of compound eyes at night, under low-light conditions, by increasing the summation time of light entering the eye to generate a response.