Development of projection neuron types, axon pathways, and patterned connections of the mammalian cortex

The mammalian neocortex processes visual, auditory, and somatic sensation, giving rise to perception and initiatingvoluntarymotor responses.Thesefunctions are performed through an intricate set of neural circuits within the neocortex, as well as through connections between the cortex and other parts of the brain. Neural scientists have long been intrigued with these connections, as indicated in the following passage written a century ago by Santiago Ramon y Cajal.