The projections of the lateral geniculate nucleus of the squirrel monkey: studies of the interlaminar zones and the S layers.

Anterograde and retrograde tracing techniques were used to reveal that axons arising from neurons within the interlaminar zones and the S layers of the lateral geniculate nucleus of the squirrel monkey terminate within the supragranular layers of area 17. Specifically, our data indicate that the axons of the neurons housed within the S layers end in a patchlike fashion in cortical layers IIIa and IIIb, while neurons in the interlaminar zones project primarily to layer I. Both pathways may convey W-cell information from the retina and the superior colliculus to the striate cortex.