Resolving single cone inputs to visual receptive fields

Abstract
Current techniques are insufficient for resolving the contribution of single photoreceptors to the responses of visually responsive neurons in the brain. Here, the authors employ a new technique, which utilizes adaptive optics, to show that LGN neurons respond reliably to the stimulation of a single cone. With the current techniques available for mapping receptive fields, it is impossible to resolve the contribution of single cone photoreceptors to the response of central visual neurons. Using adaptive optics to correct for ocular aberrations, we delivered micron-scale spots of light to the receptive field centers of neurons in the macaque lateral geniculate nucleus. Parvocellular LGN neurons mapped in this manner responded with high reliability to stimulation of single cones.