Components of the ERG of the moth, Galleria mellonella

Abstract

Abstract Origin of the components of the electroretinogram of the moth Galleria mellonella have been investigated. Successive recordings taken at different depths through the retina and optic ganglion indicate that the positive and maintained negative phases of the ERG originate in the retina while a phasic negative potential occurs in the ganglion, but under certain conditions may invade the retina too. There appears to be no correlation between amplitude and adaptation for the positive and slow negative phases nor will agents applied to the ganglion obliterate the positive phase. If either NaCl or Ringer solution is applied to the retina the positive phase is abolished. Isotonic KCl does not have this effect. Ringer's and NaCl applied to the ganglion do not affect the ERG. Damage to the retinal basement membrane also appears to abolish the positive phase. We interpret these effects to indicate the ion-selective permeability of the basement membrane.