Studies on the visual thalamic relays, the lateral geniculate nucleus and pulvinar, provide
three key properties that have dramatically changed the view that the thalamus serves as a
simple relay to get information from subcortical sites to cortex. First, the retinal input,
although a small minority (7%) in terms of numbers of synapses onto geniculate relay cells,
dominates receptive field properties of these relay cells and strongly drives them; 93% of
input thus is nonretinal and modulates the relay in dynamic and important ways related to …