When spines on the scape and pedicel of two species of saturnid moths were irradiated with visible coherent (6328 Å) and incoherent radiation, the sensors responded to the light by sending a biphasic nerve impulse down the entire length of the central antennal nerve. The biphasic action potential apparently gates the antennae and prevents the moth from responding to environmental signals during daylight.
P. S. Callahan, "A High Frequency Dielectric Waveguide on the Antennae of Night-Flying Moths (Saturnidae)," Appl. Opt. 7, 1425-1430 (1968)