Influence of flicker frequency on flicker-induced changes of retinal vessel diameter.

The flicker-induced diameter response of the larger retinal arteries and veins can be continuously measured with a modified RVA system that spectrally separates the flicker stimulation from the fundus illumination light. Vasodilation of retinal arteries was observed in response to short wavelength flicker with frequencies between 2 and 64 Hz, indicating that the parvo- and magnocellular neural pathways are activated with this stimulation.