Phasic and Tonic Cells in the Cat's Lateral Geniculate Nucleus

Abstract

Relay neurons in the cat's lateral geniculate nucleus have either on-center or off-center receptive field. They are further classified into Type-I (phasic) and Type-II (tonic). Type-I cells are activated by faster conducting opfic tract fibers and send the visual information to visual cortex by faster conducting radiation fibers, while Type-II cells area ctivated by slower fibers and extend slower radiation fibers, while Type-II cells are activated by slower fibers and extend slower radiation fibers, while Type-II cells are activated by slower fibers and extend slower radiation fibers.